Linux preempt-rt

Check our new training course

Real-Time Linux with PREEMPT_RT

Check our new training course
with Creative Commons CC-BY-SA
lecture and lab materials

Bootlin logo

Elixir Cross Referencer

   1
   2
   3
   4
   5
   6
   7
   8
   9
  10
  11
  12
  13
  14
  15
  16
  17
  18
  19
  20
  21
  22
  23
  24
  25
  26
  27
  28
  29
  30
  31
  32
  33
  34
  35
  36
  37
  38
  39
  40
  41
  42
  43
  44
  45
  46
  47
  48
  49
  50
  51
  52
  53
  54
  55
  56
  57
  58
  59
  60
  61
  62
  63
  64
  65
  66
  67
  68
  69
  70
  71
  72
  73
  74
  75
  76
  77
  78
  79
  80
  81
  82
  83
  84
  85
  86
  87
  88
  89
  90
  91
  92
  93
  94
  95
  96
  97
  98
  99
 100
 101
 102
 103
 104
 105
 106
 107
 108
 109
 110
 111
 112
 113
 114
 115
 116
 117
 118
 119
 120
 121
 122
 123
 124
 125
 126
 127
 128
 129
 130
 131
 132
 133
 134
 135
 136
 137
 138
 139
 140
 141
 142
 143
 144
 145
 146
 147
 148
 149
 150
 151
 152
 153
 154
 155
 156
 157
 158
 159
 160
 161
 162
 163
 164
 165
 166
 167
 168
 169
 170
 171
 172
 173
 174
 175
 176
 177
 178
 179
 180
 181
 182
 183
 184
 185
 186
 187
 188
 189
 190
 191
 192
 193
 194
 195
 196
 197
 198
 199
 200
 201
 202
 203
 204
 205
 206
 207
 208
 209
 210
 211
 212
 213
 214
 215
 216
 217
 218
 219
 220
 221
 222
 223
 224
 225
 226
 227
 228
 229
 230
 231
 232
 233
 234
 235
 236
 237
 238
 239
 240
 241
 242
 243
 244
 245
 246
 247
 248
 249
 250
 251
 252
 253
 254
 255
 256
 257
 258
 259
 260
 261
 262
 263
 264
 265
 266
 267
 268
 269
 270
 271
 272
 273
 274
 275
 276
 277
 278
 279
 280
 281
 282
 283
 284
 285
 286
 287
 288
 289
 290
 291
 292
 293
 294
 295
 296
 297
 298
 299
 300
 301
 302
 303
 304
 305
 306
 307
 308
 309
 310
 311
 312
 313
 314
 315
 316
 317
 318
 319
 320
 321
 322
 323
 324
 325
 326
 327
 328
 329
 330
 331
 332
 333
 334
 335
 336
 337
 338
 339
 340
 341
 342
 343
 344
 345
 346
 347
 348
 349
 350
 351
 352
 353
 354
 355
 356
 357
 358
 359
 360
 361
 362
 363
 364
 365
 366
 367
 368
 369
 370
 371
 372
 373
 374
 375
 376
 377
 378
 379
 380
 381
 382
 383
 384
 385
 386
 387
 388
 389
 390
 391
 392
 393
 394
 395
 396
 397
 398
 399
 400
 401
 402
 403
 404
 405
 406
 407
 408
 409
 410
 411
 412
 413
 414
 415
 416
 417
 418
 419
 420
 421
 422
 423
 424
 425
 426
 427
 428
 429
 430
 431
 432
 433
 434
 435
 436
 437
 438
 439
 440
 441
 442
 443
 444
 445
 446
 447
 448
 449
 450
 451
 452
 453
 454
 455
 456
 457
 458
 459
 460
 461
 462
 463
 464
 465
 466
 467
 468
 469
 470
 471
 472
 473
 474
 475
 476
 477
 478
 479
 480
 481
 482
 483
 484
 485
 486
 487
 488
 489
 490
 491
 492
 493
 494
 495
 496
 497
 498
 499
 500
 501
 502
 503
 504
 505
 506
 507
 508
 509
 510
 511
 512
 513
 514
 515
 516
 517
 518
 519
 520
 521
 522
 523
 524
 525
 526
 527
 528
 529
 530
 531
 532
 533
 534
 535
 536
 537
 538
 539
 540
 541
 542
 543
 544
 545
 546
 547
 548
 549
 550
 551
 552
 553
 554
 555
 556
 557
 558
 559
 560
 561
 562
 563
 564
 565
 566
 567
 568
 569
 570
 571
 572
 573
 574
 575
 576
 577
 578
 579
 580
 581
 582
 583
 584
 585
 586
 587
 588
 589
 590
 591
 592
 593
 594
 595
 596
 597
 598
 599
 600
 601
 602
 603
 604
 605
 606
 607
 608
 609
 610
 611
 612
 613
 614
 615
 616
 617
 618
 619
 620
 621
 622
 623
 624
 625
 626
 627
 628
 629
 630
 631
 632
 633
 634
 635
 636
 637
 638
 639
 640
 641
 642
 643
 644
 645
 646
 647
 648
 649
 650
 651
 652
 653
 654
 655
 656
 657
 658
 659
 660
 661
 662
 663
 664
 665
 666
 667
 668
 669
 670
 671
 672
 673
 674
 675
 676
 677
 678
 679
 680
 681
 682
 683
 684
 685
 686
 687
 688
 689
 690
 691
 692
 693
 694
 695
 696
 697
 698
 699
 700
 701
 702
 703
 704
 705
 706
 707
 708
 709
 710
 711
 712
 713
 714
 715
 716
 717
 718
 719
 720
 721
 722
 723
 724
 725
 726
 727
 728
 729
 730
 731
 732
 733
 734
 735
 736
 737
 738
 739
 740
 741
 742
 743
 744
 745
 746
 747
 748
 749
 750
 751
 752
 753
 754
 755
 756
 757
 758
 759
 760
 761
 762
 763
 764
 765
 766
 767
 768
 769
 770
 771
 772
 773
 774
 775
 776
 777
 778
 779
 780
 781
 782
 783
 784
 785
 786
 787
 788
 789
 790
 791
 792
 793
 794
 795
 796
 797
 798
 799
 800
 801
 802
 803
 804
 805
 806
 807
 808
 809
 810
 811
 812
 813
 814
 815
 816
 817
 818
 819
 820
 821
 822
 823
 824
 825
 826
 827
 828
 829
 830
 831
 832
 833
 834
 835
 836
 837
 838
 839
 840
 841
 842
 843
 844
 845
 846
 847
 848
 849
 850
 851
 852
 853
 854
 855
 856
 857
 858
 859
 860
 861
 862
 863
 864
 865
 866
 867
 868
 869
 870
 871
 872
 873
 874
 875
 876
 877
 878
 879
 880
 881
 882
 883
 884
 885
 886
 887
 888
 889
 890
 891
 892
 893
 894
 895
 896
 897
 898
 899
 900
 901
 902
 903
 904
 905
 906
 907
 908
 909
 910
 911
 912
 913
 914
 915
 916
 917
 918
 919
 920
 921
 922
 923
 924
 925
 926
 927
 928
 929
 930
 931
 932
 933
 934
 935
 936
 937
 938
 939
 940
 941
 942
 943
 944
 945
 946
 947
 948
 949
 950
 951
 952
 953
 954
 955
 956
 957
 958
 959
 960
 961
 962
 963
 964
 965
 966
 967
 968
 969
 970
 971
 972
 973
 974
 975
 976
 977
 978
 979
 980
 981
 982
 983
 984
 985
 986
 987
 988
 989
 990
 991
 992
 993
 994
 995
 996
 997
 998
 999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621
3622
3623
3624
3625
3626
3627
3628
3629
3630
3631
3632
3633
3634
3635
3636
3637
3638
3639
3640
3641
3642
3643
3644
3645
3646
3647
3648
3649
3650
3651
3652
3653
3654
3655
3656
3657
3658
3659
3660
3661
3662
3663
3664
3665
3666
3667
3668
3669
3670
3671
3672
3673
3674
3675
3676
3677
3678
3679
3680
3681
3682
3683
3684
3685
3686
3687
3688
3689
3690
3691
3692
3693
3694
3695
3696
3697
3698
3699
3700
3701
3702
3703
3704
3705
3706
3707
3708
3709
3710
3711
3712
3713
3714
3715
3716
3717
3718
3719
3720
3721
3722
3723
3724
3725
3726
3727
3728
3729
3730
3731
3732
3733
3734
3735
3736
3737
3738
3739
3740
3741
3742
3743
3744
3745
3746
3747
3748
3749
3750
3751
3752
3753
3754
3755
3756
3757
3758
3759
3760
3761
3762
3763
3764
3765
3766
3767
3768
3769
3770
3771
3772
3773
3774
3775
3776
3777
3778
3779
3780
3781
3782
3783
3784
3785
3786
3787
3788
3789
3790
3791
3792
3793
3794
3795
3796
3797
3798
3799
3800
3801
3802
3803
3804
3805
3806
3807
3808
3809
3810
3811
3812
3813
3814
3815
3816
3817
3818
3819
3820
3821
3822
3823
3824
3825
3826
3827
3828
3829
3830
3831
3832
3833
3834
3835
3836
3837
3838
3839
3840
3841
3842
3843
3844
3845
3846
3847
3848
3849
3850
3851
3852
3853
3854
3855
3856
3857
3858
3859
3860
3861
3862
3863
3864
3865
3866
3867
3868
3869
3870
3871
3872
3873
3874
3875
3876
3877
3878
3879
3880
3881
3882
3883
3884
3885
3886
3887
3888
3889
3890
3891
3892
3893
3894
3895
3896
3897
3898
3899
3900
3901
3902
3903
3904
3905
3906
3907
3908
3909
3910
3911
3912
3913
3914
3915
3916
3917
3918
3919
3920
3921
3922
3923
3924
3925
3926
3927
3928
3929
3930
3931
3932
3933
3934
3935
3936
3937
3938
3939
3940
3941
3942
3943
3944
3945
3946
3947
3948
3949
3950
3951
3952
3953
3954
3955
3956
3957
3958
3959
3960
3961
3962
3963
3964
3965
3966
3967
3968
3969
3970
3971
3972
3973
3974
3975
3976
3977
3978
3979
3980
3981
3982
3983
3984
3985
3986
3987
3988
3989
3990
3991
3992
3993
3994
3995
3996
3997
3998
3999
4000
4001
4002
4003
4004
4005
4006
4007
4008
4009
4010
4011
4012
4013
4014
4015
4016
4017
4018
4019
4020
4021
4022
4023
4024
4025
4026
4027
4028
4029
4030
4031
4032
4033
4034
4035
4036
4037
4038
4039
4040
4041
4042
4043
4044
4045
4046
4047
4048
4049
4050
4051
4052
4053
4054
4055
4056
4057
4058
4059
4060
4061
4062
4063
4064
4065
4066
4067
4068
4069
4070
4071
4072
4073
4074
4075
4076
4077
4078
4079
4080
4081
4082
4083
4084
4085
4086
4087
4088
4089
4090
4091
4092
4093
4094
4095
4096
4097
4098
4099
4100
4101
4102
4103
4104
4105
4106
4107
4108
4109
4110
4111
4112
4113
4114
4115
4116
4117
4118
4119
4120
4121
4122
4123
4124
4125
4126
4127
4128
4129
4130
4131
4132
4133
4134
4135
4136
4137
4138
4139
4140
4141
4142
4143
4144
4145
4146
4147
4148
4149
4150
4151
4152
4153
4154
4155
4156
4157
4158
4159
4160
4161
4162
4163
4164
4165
4166
4167
4168
4169
4170
4171
4172
4173
4174
4175
4176
4177
4178
4179
4180
4181
4182
4183
4184
4185
4186
4187
4188
4189
4190
4191
4192
4193
4194
4195
4196
4197
4198
4199
4200
4201
4202
4203
4204
4205
4206
4207
4208
4209
4210
4211
4212
4213
4214
4215
4216
4217
4218
4219
4220
4221
4222
4223
4224
4225
4226
4227
4228
4229
4230
4231
4232
4233
4234
4235
4236
4237
4238
4239
4240
4241
4242
4243
4244
4245
4246
4247
4248
4249
4250
4251
4252
4253
4254
4255
4256
4257
4258
4259
4260
4261
4262
4263
4264
4265
4266
4267
4268
4269
4270
4271
4272
4273
4274
4275
4276
4277
4278
4279
4280
4281
4282
4283
4284
4285
4286
4287
4288
4289
4290
4291
4292
4293
4294
4295
4296
4297
4298
4299
4300
4301
4302
4303
4304
4305
4306
4307
4308
4309
4310
4311
4312
4313
4314
4315
4316
4317
4318
4319
4320
4321
4322
4323
4324
4325
4326
4327
4328
4329
4330
4331
4332
4333
4334
4335
4336
4337
4338
4339
4340
4341
4342
4343
4344
4345
4346
4347
4348
4349
4350
4351
4352
4353
4354
4355
4356
4357
4358
4359
4360
4361
4362
4363
4364
4365
4366
4367
4368
4369
4370
4371
4372
4373
4374
4375
4376
4377
4378
4379
4380
4381
4382
4383
4384
4385
4386
4387
4388
4389
4390
4391
4392
4393
4394
4395
4396
4397
4398
4399
4400
4401
4402
4403
4404
4405
4406
4407
4408
4409
4410
4411
4412
4413
4414
4415
4416
4417
4418
4419
4420
4421
4422
4423
4424
4425
4426
4427
4428
4429
4430
4431
4432
4433
4434
4435
4436
4437
4438
4439
4440
4441
4442
4443
4444
4445
4446
4447
4448
4449
4450
4451
4452
4453
4454
4455
4456
4457
4458
4459
4460
4461
4462
4463
4464
4465
4466
4467
4468
4469
4470
4471
4472
4473
4474
4475
4476
4477
4478
4479
4480
4481
4482
4483
4484
4485
4486
4487
4488
4489
4490
4491
4492
4493
4494
4495
4496
4497
4498
4499
4500
4501
4502
4503
4504
4505
4506
4507
4508
4509
4510
4511
4512
4513
4514
4515
4516
4517
4518
4519
4520
4521
4522
4523
4524
4525
4526
4527
4528
4529
4530
4531
4532
4533
4534
4535
4536
4537
4538
4539
4540
4541
4542
4543
4544
4545
4546
4547
4548
4549
4550
4551
4552
4553
4554
4555
4556
4557
4558
4559
4560
4561
4562
4563
4564
4565
4566
4567
4568
4569
4570
4571
4572
4573
4574
4575
4576
4577
4578
4579
4580
4581
4582
4583
4584
4585
4586
4587
4588
4589
4590
4591
4592
4593
4594
4595
4596
4597
4598
4599
4600
4601
4602
4603
4604
4605
4606
4607
4608
4609
4610
4611
4612
4613
4614
4615
4616
4617
4618
4619
4620
4621
4622
4623
4624
4625
4626
4627
4628
4629
4630
4631
4632
4633
4634
4635
4636
4637
4638
4639
4640
4641
4642
4643
4644
4645
4646
4647
4648
4649
4650
4651
4652
4653
4654
4655
4656
4657
4658
4659
4660
4661
4662
4663
4664
4665
4666
4667
4668
4669
4670
4671
4672
4673
4674
4675
4676
4677
4678
4679
4680
4681
4682
4683
4684
4685
4686
4687
4688
4689
4690
4691
4692
4693
4694
4695
4696
4697
4698
4699
4700
4701
4702
4703
4704
4705
4706
4707
4708
4709
4710
4711
4712
4713
4714
4715
4716
4717
4718
4719
4720
4721
4722
4723
4724
4725
4726
4727
4728
4729
4730
4731
4732
4733
4734
4735
4736
4737
4738
4739
4740
4741
4742
4743
4744
4745
4746
4747
4748
4749
4750
4751
4752
4753
4754
4755
4756
4757
4758
4759
4760
4761
4762
4763
4764
4765
4766
4767
4768
4769
4770
4771
4772
4773
4774
4775
4776
4777
4778
4779
4780
4781
4782
4783
4784
4785
4786
4787
4788
4789
4790
4791
4792
4793
4794
4795
4796
4797
4798
4799
4800
4801
4802
4803
4804
4805
4806
4807
4808
4809
4810
4811
4812
4813
4814
4815
4816
4817
4818
4819
4820
4821
4822
4823
4824
4825
4826
4827
4828
4829
4830
4831
4832
4833
4834
4835
4836
4837
4838
4839
4840
4841
4842
4843
4844
4845
4846
4847
4848
4849
4850
4851
4852
4853
4854
4855
4856
4857
4858
4859
4860
4861
4862
4863
4864
4865
4866
4867
4868
4869
4870
4871
4872
4873
4874
4875
4876
4877
4878
4879
4880
4881
4882
4883
4884
4885
4886
4887
4888
4889
4890
4891
4892
4893
4894
4895
4896
4897
4898
4899
4900
4901
4902
4903
4904
4905
4906
4907
4908
4909
4910
4911
4912
4913
4914
4915
4916
4917
4918
4919
4920
4921
4922
4923
4924
4925
4926
4927
4928
4929
4930
4931
4932
4933
4934
4935
4936
4937
4938
4939
4940
4941
4942
4943
4944
4945
4946
4947
4948
4949
4950
4951
4952
4953
4954
4955
4956
4957
4958
4959
4960
4961
4962
4963
4964
4965
4966
4967
4968
4969
4970
4971
4972
4973
4974
4975
4976
4977
4978
4979
4980
4981
4982
4983
4984
4985
4986
4987
4988
4989
4990
4991
4992
4993
4994
4995
4996
4997
4998
4999
5000
5001
5002
5003
5004
5005
5006
5007
5008
5009
5010
5011
5012
5013
5014
5015
5016
5017
5018
5019
5020
5021
5022
5023
5024
5025
5026
5027
5028
5029
5030
5031
5032
5033
5034
5035
5036
5037
5038
5039
5040
5041
5042
5043
5044
5045
5046
5047
5048
5049
5050
5051
5052
5053
5054
5055
5056
5057
5058
5059
5060
5061
5062
5063
5064
5065
5066
5067
5068
5069
5070
5071
5072
5073
5074
5075
5076
5077
5078
5079
5080
5081
5082
5083
5084
5085
5086
5087
5088
5089
5090
5091
5092
5093
5094
5095
5096
5097
5098
5099
5100
5101
5102
5103
5104
5105
5106
5107
5108
5109
5110
5111
5112
5113
5114
5115
5116
5117
5118
5119
5120
5121
5122
5123
5124
5125
5126
5127
5128
5129
5130
5131
5132
5133
5134
5135
5136
5137
5138
5139
5140
5141
5142
5143
5144
5145
5146
5147
5148
5149
5150
5151
5152
5153
5154
5155
5156
5157
5158
5159
5160
5161
5162
5163
5164
5165
5166
5167
5168
5169
5170
5171
5172
5173
5174
5175
5176
5177
5178
5179
5180
5181
5182
5183
5184
5185
5186
5187
5188
5189
5190
5191
5192
5193
5194
5195
5196
5197
5198
5199
5200
5201
5202
5203
5204
5205
5206
5207
5208
5209
5210
5211
5212
5213
5214
5215
5216
5217
5218
5219
5220
5221
5222
5223
5224
5225
5226
5227
5228
5229
5230
5231
5232
5233
5234
5235
5236
5237
5238
5239
5240
5241
5242
5243
5244
5245
5246
5247
5248
5249
5250
5251
5252
5253
5254
5255
5256
5257
5258
5259
5260
5261
5262
5263
5264
5265
5266
5267
5268
5269
5270
5271
5272
5273
5274
5275
5276
5277
5278
5279
5280
5281
5282
5283
5284
5285
5286
5287
5288
5289
5290
5291
5292
5293
5294
5295
5296
5297
5298
5299
5300
5301
5302
5303
5304
5305
5306
5307
5308
5309
5310
5311
5312
5313
5314
5315
5316
5317
5318
5319
5320
5321
5322
5323
5324
5325
5326
5327
5328
5329
5330
5331
5332
5333
5334
5335
5336
5337
5338
5339
5340
5341
5342
5343
5344
5345
5346
5347
5348
5349
5350
5351
5352
5353
5354
5355
5356
5357
5358
5359
5360
5361
5362
5363
5364
5365
5366
5367
5368
5369
5370
5371
5372
5373
5374
5375
5376
5377
5378
5379
5380
5381
5382
5383
5384
5385
5386
5387
5388
5389
5390
5391
5392
5393
5394
5395
5396
5397
5398
5399
5400
5401
5402
5403
5404
5405
HXCOMM Use DEFHEADING() to define headings in both help text and rST.
HXCOMM Text between SRST and ERST is copied to the rST version and
HXCOMM discarded from C version.
HXCOMM DEF(option, HAS_ARG/0, opt_enum, opt_help, arch_mask) is used to
HXCOMM construct option structures, enums and help message for specified
HXCOMM architectures.
HXCOMM HXCOMM can be used for comments, discarded from both rST and C.

DEFHEADING(Standard options:)

DEF("help", 0, QEMU_OPTION_h,
    "-h or -help     display this help and exit\n", QEMU_ARCH_ALL)
SRST
``-h``
    Display help and exit
ERST

DEF("version", 0, QEMU_OPTION_version,
    "-version        display version information and exit\n", QEMU_ARCH_ALL)
SRST
``-version``
    Display version information and exit
ERST

DEF("machine", HAS_ARG, QEMU_OPTION_machine, \
    "-machine [type=]name[,prop[=value][,...]]\n"
    "                selects emulated machine ('-machine help' for list)\n"
    "                property accel=accel1[:accel2[:...]] selects accelerator\n"
    "                supported accelerators are kvm, xen, hax, hvf, nvmm, whpx or tcg (default: tcg)\n"
    "                vmport=on|off|auto controls emulation of vmport (default: auto)\n"
    "                dump-guest-core=on|off include guest memory in a core dump (default=on)\n"
    "                mem-merge=on|off controls memory merge support (default: on)\n"
    "                aes-key-wrap=on|off controls support for AES key wrapping (default=on)\n"
    "                dea-key-wrap=on|off controls support for DEA key wrapping (default=on)\n"
    "                suppress-vmdesc=on|off disables self-describing migration (default=off)\n"
    "                nvdimm=on|off controls NVDIMM support (default=off)\n"
    "                memory-encryption=@var{} memory encryption object to use (default=none)\n"
    "                hmat=on|off controls ACPI HMAT support (default=off)\n"
    "                memory-backend='backend-id' specifies explicitly provided backend for main RAM (default=none)\n",
    QEMU_ARCH_ALL)
SRST
``-machine [type=]name[,prop=value[,...]]``
    Select the emulated machine by name. Use ``-machine help`` to list
    available machines.

    For architectures which aim to support live migration compatibility
    across releases, each release will introduce a new versioned machine
    type. For example, the 2.8.0 release introduced machine types
    "pc-i440fx-2.8" and "pc-q35-2.8" for the x86\_64/i686 architectures.

    To allow live migration of guests from QEMU version 2.8.0, to QEMU
    version 2.9.0, the 2.9.0 version must support the "pc-i440fx-2.8"
    and "pc-q35-2.8" machines too. To allow users live migrating VMs to
    skip multiple intermediate releases when upgrading, new releases of
    QEMU will support machine types from many previous versions.

    Supported machine properties are:

    ``accel=accels1[:accels2[:...]]``
        This is used to enable an accelerator. Depending on the target
        architecture, kvm, xen, hax, hvf, nvmm, whpx or tcg can be available.
        By default, tcg is used. If there is more than one accelerator
        specified, the next one is used if the previous one fails to
        initialize.

    ``vmport=on|off|auto``
        Enables emulation of VMWare IO port, for vmmouse etc. auto says
        to select the value based on accel. For accel=xen the default is
        off otherwise the default is on.

    ``dump-guest-core=on|off``
        Include guest memory in a core dump. The default is on.

    ``mem-merge=on|off``
        Enables or disables memory merge support. This feature, when
        supported by the host, de-duplicates identical memory pages
        among VMs instances (enabled by default).

    ``aes-key-wrap=on|off``
        Enables or disables AES key wrapping support on s390-ccw hosts.
        This feature controls whether AES wrapping keys will be created
        to allow execution of AES cryptographic functions. The default
        is on.

    ``dea-key-wrap=on|off``
        Enables or disables DEA key wrapping support on s390-ccw hosts.
        This feature controls whether DEA wrapping keys will be created
        to allow execution of DEA cryptographic functions. The default
        is on.

    ``nvdimm=on|off``
        Enables or disables NVDIMM support. The default is off.

    ``memory-encryption=``
        Memory encryption object to use. The default is none.

    ``hmat=on|off``
        Enables or disables ACPI Heterogeneous Memory Attribute Table
        (HMAT) support. The default is off.

    ``memory-backend='id'``
        An alternative to legacy ``-mem-path`` and ``mem-prealloc`` options.
        Allows to use a memory backend as main RAM.

        For example:
        ::

            -object memory-backend-file,id=pc.ram,size=512M,mem-path=/hugetlbfs,prealloc=on,share=on
            -machine memory-backend=pc.ram
            -m 512M

        Migration compatibility note:

        * as backend id one shall use value of 'default-ram-id', advertised by
          machine type (available via ``query-machines`` QMP command), if migration
          to/from old QEMU (<5.0) is expected.
        * for machine types 4.0 and older, user shall
          use ``x-use-canonical-path-for-ramblock-id=off`` backend option
          if migration to/from old QEMU (<5.0) is expected.

        For example:
        ::

            -object memory-backend-ram,id=pc.ram,size=512M,x-use-canonical-path-for-ramblock-id=off
            -machine memory-backend=pc.ram
            -m 512M
ERST

DEF("M", HAS_ARG, QEMU_OPTION_M,
    "                sgx-epc.0.memdev=memid\n",
    QEMU_ARCH_ALL)

SRST
``sgx-epc.0.memdev=@var{memid}``
    Define an SGX EPC section.
ERST

DEF("cpu", HAS_ARG, QEMU_OPTION_cpu,
    "-cpu cpu        select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL)
SRST
``-cpu model``
    Select CPU model (``-cpu help`` for list and additional feature
    selection)
ERST

DEF("accel", HAS_ARG, QEMU_OPTION_accel,
    "-accel [accel=]accelerator[,prop[=value][,...]]\n"
    "                select accelerator (kvm, xen, hax, hvf, nvmm, whpx or tcg; use 'help' for a list)\n"
    "                igd-passthru=on|off (enable Xen integrated Intel graphics passthrough, default=off)\n"
    "                kernel-irqchip=on|off|split controls accelerated irqchip support (default=on)\n"
    "                kvm-shadow-mem=size of KVM shadow MMU in bytes\n"
    "                split-wx=on|off (enable TCG split w^x mapping)\n"
    "                tb-size=n (TCG translation block cache size)\n"
    "                dirty-ring-size=n (KVM dirty ring GFN count, default 0)\n"
    "                thread=single|multi (enable multi-threaded TCG)\n", QEMU_ARCH_ALL)
SRST
``-accel name[,prop=value[,...]]``
    This is used to enable an accelerator. Depending on the target
    architecture, kvm, xen, hax, hvf, nvmm, whpx or tcg can be available. By
    default, tcg is used. If there is more than one accelerator
    specified, the next one is used if the previous one fails to
    initialize.

    ``igd-passthru=on|off``
        When Xen is in use, this option controls whether Intel
        integrated graphics devices can be passed through to the guest
        (default=off)

    ``kernel-irqchip=on|off|split``
        Controls KVM in-kernel irqchip support. The default is full
        acceleration of the interrupt controllers. On x86, split irqchip
        reduces the kernel attack surface, at a performance cost for
        non-MSI interrupts. Disabling the in-kernel irqchip completely
        is not recommended except for debugging purposes.

    ``kvm-shadow-mem=size``
        Defines the size of the KVM shadow MMU.

    ``split-wx=on|off``
        Controls the use of split w^x mapping for the TCG code generation
        buffer. Some operating systems require this to be enabled, and in
        such a case this will default on. On other operating systems, this
        will default off, but one may enable this for testing or debugging.

    ``tb-size=n``
        Controls the size (in MiB) of the TCG translation block cache.

    ``thread=single|multi``
        Controls number of TCG threads. When the TCG is multi-threaded
        there will be one thread per vCPU therefore taking advantage of
        additional host cores. The default is to enable multi-threading
        where both the back-end and front-ends support it and no
        incompatible TCG features have been enabled (e.g.
        icount/replay).

    ``dirty-ring-size=n``
        When the KVM accelerator is used, it controls the size of the per-vCPU
        dirty page ring buffer (number of entries for each vCPU). It should
        be a value that is power of two, and it should be 1024 or bigger (but
        still less than the maximum value that the kernel supports).  4096
        could be a good initial value if you have no idea which is the best.
        Set this value to 0 to disable the feature.  By default, this feature
        is disabled (dirty-ring-size=0).  When enabled, KVM will instead
        record dirty pages in a bitmap.

ERST

DEF("smp", HAS_ARG, QEMU_OPTION_smp,
    "-smp [[cpus=]n][,maxcpus=maxcpus][,sockets=sockets][,dies=dies][,cores=cores][,threads=threads]\n"
    "                set the number of CPUs to 'n' [default=1]\n"
    "                maxcpus= maximum number of total CPUs, including\n"
    "                offline CPUs for hotplug, etc\n"
    "                sockets= number of discrete sockets in the system\n"
    "                dies= number of CPU dies on one socket (for PC only)\n"
    "                cores= number of CPU cores on one socket (for PC, it's on one die)\n"
    "                threads= number of threads on one CPU core\n",
        QEMU_ARCH_ALL)
SRST
``-smp [[cpus=]n][,maxcpus=maxcpus][,sockets=sockets][,dies=dies][,cores=cores][,threads=threads]``
    Simulate a SMP system with '\ ``n``\ ' CPUs initially present on
    the machine type board. On boards supporting CPU hotplug, the optional
    '\ ``maxcpus``\ ' parameter can be set to enable further CPUs to be
    added at runtime. When both parameters are omitted, the maximum number
    of CPUs will be calculated from the provided topology members and the
    initial CPU count will match the maximum number. When only one of them
    is given then the omitted one will be set to its counterpart's value.
    Both parameters may be specified, but the maximum number of CPUs must
    be equal to or greater than the initial CPU count. Both parameters are
    subject to an upper limit that is determined by the specific machine
    type chosen.

    To control reporting of CPU topology information, the number of sockets,
    dies per socket, cores per die, and threads per core can be specified.
    The sum `` sockets * cores * dies * threads `` must be equal to the
    maximum CPU count. CPU targets may only support a subset of the topology
    parameters. Where a CPU target does not support use of a particular
    topology parameter, its value should be assumed to be 1 for the purpose
    of computing the CPU maximum count.

    Either the initial CPU count, or at least one of the topology parameters
    must be specified. The specified parameters must be greater than zero,
    explicit configuration like "cpus=0" is not allowed. Values for any
    omitted parameters will be computed from those which are given.
    Historically preference was given to the coarsest topology parameters
    when computing missing values (ie sockets preferred over cores, which
    were preferred over threads), however, this behaviour is considered
    liable to change. Prior to 6.2 the preference was sockets over cores
    over threads. Since 6.2 the preference is cores over sockets over threads.
ERST

DEF("numa", HAS_ARG, QEMU_OPTION_numa,
    "-numa node[,mem=size][,cpus=firstcpu[-lastcpu]][,nodeid=node][,initiator=node]\n"
    "-numa node[,memdev=id][,cpus=firstcpu[-lastcpu]][,nodeid=node][,initiator=node]\n"
    "-numa dist,src=source,dst=destination,val=distance\n"
    "-numa cpu,node-id=node[,socket-id=x][,core-id=y][,thread-id=z]\n"
    "-numa hmat-lb,initiator=node,target=node,hierarchy=memory|first-level|second-level|third-level,data-type=access-latency|read-latency|write-latency[,latency=lat][,bandwidth=bw]\n"
    "-numa hmat-cache,node-id=node,size=size,level=level[,associativity=none|direct|complex][,policy=none|write-back|write-through][,line=size]\n",
    QEMU_ARCH_ALL)
SRST
``-numa node[,mem=size][,cpus=firstcpu[-lastcpu]][,nodeid=node][,initiator=initiator]``
  \ 
``-numa node[,memdev=id][,cpus=firstcpu[-lastcpu]][,nodeid=node][,initiator=initiator]``
  \
``-numa dist,src=source,dst=destination,val=distance``
  \ 
``-numa cpu,node-id=node[,socket-id=x][,core-id=y][,thread-id=z]``
  \ 
``-numa hmat-lb,initiator=node,target=node,hierarchy=hierarchy,data-type=tpye[,latency=lat][,bandwidth=bw]``
  \ 
``-numa hmat-cache,node-id=node,size=size,level=level[,associativity=str][,policy=str][,line=size]``
    Define a NUMA node and assign RAM and VCPUs to it. Set the NUMA
    distance from a source node to a destination node. Set the ACPI
    Heterogeneous Memory Attributes for the given nodes.

    Legacy VCPU assignment uses '\ ``cpus``\ ' option where firstcpu and
    lastcpu are CPU indexes. Each '\ ``cpus``\ ' option represent a
    contiguous range of CPU indexes (or a single VCPU if lastcpu is
    omitted). A non-contiguous set of VCPUs can be represented by
    providing multiple '\ ``cpus``\ ' options. If '\ ``cpus``\ ' is
    omitted on all nodes, VCPUs are automatically split between them.

    For example, the following option assigns VCPUs 0, 1, 2 and 5 to a
    NUMA node:

    ::

        -numa node,cpus=0-2,cpus=5

    '\ ``cpu``\ ' option is a new alternative to '\ ``cpus``\ ' option
    which uses '\ ``socket-id|core-id|thread-id``\ ' properties to
    assign CPU objects to a node using topology layout properties of
    CPU. The set of properties is machine specific, and depends on used
    machine type/'\ ``smp``\ ' options. It could be queried with
    '\ ``hotpluggable-cpus``\ ' monitor command. '\ ``node-id``\ '
    property specifies node to which CPU object will be assigned, it's
    required for node to be declared with '\ ``node``\ ' option before
    it's used with '\ ``cpu``\ ' option.

    For example:

    ::

        -M pc \
        -smp 1,sockets=2,maxcpus=2 \
        -numa node,nodeid=0 -numa node,nodeid=1 \
        -numa cpu,node-id=0,socket-id=0 -numa cpu,node-id=1,socket-id=1

    Legacy '\ ``mem``\ ' assigns a given RAM amount to a node (not supported
    for 5.1 and newer machine types). '\ ``memdev``\ ' assigns RAM from
    a given memory backend device to a node. If '\ ``mem``\ ' and
    '\ ``memdev``\ ' are omitted in all nodes, RAM is split equally between them.


    '\ ``mem``\ ' and '\ ``memdev``\ ' are mutually exclusive.
    Furthermore, if one node uses '\ ``memdev``\ ', all of them have to
    use it.

    '\ ``initiator``\ ' is an additional option that points to an
    initiator NUMA node that has best performance (the lowest latency or
    largest bandwidth) to this NUMA node. Note that this option can be
    set only when the machine property 'hmat' is set to 'on'.

    Following example creates a machine with 2 NUMA nodes, node 0 has
    CPU. node 1 has only memory, and its initiator is node 0. Note that
    because node 0 has CPU, by default the initiator of node 0 is itself
    and must be itself.

    ::

        -machine hmat=on \
        -m 2G,slots=2,maxmem=4G \
        -object memory-backend-ram,size=1G,id=m0 \
        -object memory-backend-ram,size=1G,id=m1 \
        -numa node,nodeid=0,memdev=m0 \
        -numa node,nodeid=1,memdev=m1,initiator=0 \
        -smp 2,sockets=2,maxcpus=2  \
        -numa cpu,node-id=0,socket-id=0 \
        -numa cpu,node-id=0,socket-id=1

    source and destination are NUMA node IDs. distance is the NUMA
    distance from source to destination. The distance from a node to
    itself is always 10. If any pair of nodes is given a distance, then
    all pairs must be given distances. Although, when distances are only
    given in one direction for each pair of nodes, then the distances in
    the opposite directions are assumed to be the same. If, however, an
    asymmetrical pair of distances is given for even one node pair, then
    all node pairs must be provided distance values for both directions,
    even when they are symmetrical. When a node is unreachable from
    another node, set the pair's distance to 255.

    Note that the -``numa`` option doesn't allocate any of the specified
    resources, it just assigns existing resources to NUMA nodes. This
    means that one still has to use the ``-m``, ``-smp`` options to
    allocate RAM and VCPUs respectively.

    Use '\ ``hmat-lb``\ ' to set System Locality Latency and Bandwidth
    Information between initiator and target NUMA nodes in ACPI
    Heterogeneous Attribute Memory Table (HMAT). Initiator NUMA node can
    create memory requests, usually it has one or more processors.
    Target NUMA node contains addressable memory.

    In '\ ``hmat-lb``\ ' option, node are NUMA node IDs. hierarchy is
    the memory hierarchy of the target NUMA node: if hierarchy is
    'memory', the structure represents the memory performance; if
    hierarchy is 'first-level\|second-level\|third-level', this
    structure represents aggregated performance of memory side caches
    for each domain. type of 'data-type' is type of data represented by
    this structure instance: if 'hierarchy' is 'memory', 'data-type' is
    'access\|read\|write' latency or 'access\|read\|write' bandwidth of
    the target memory; if 'hierarchy' is
    'first-level\|second-level\|third-level', 'data-type' is
    'access\|read\|write' hit latency or 'access\|read\|write' hit
    bandwidth of the target memory side cache.

    lat is latency value in nanoseconds. bw is bandwidth value, the
    possible value and units are NUM[M\|G\|T], mean that the bandwidth
    value are NUM byte per second (or MB/s, GB/s or TB/s depending on
    used suffix). Note that if latency or bandwidth value is 0, means
    the corresponding latency or bandwidth information is not provided.

    In '\ ``hmat-cache``\ ' option, node-id is the NUMA-id of the memory
    belongs. size is the size of memory side cache in bytes. level is
    the cache level described in this structure, note that the cache
    level 0 should not be used with '\ ``hmat-cache``\ ' option.
    associativity is the cache associativity, the possible value is
    'none/direct(direct-mapped)/complex(complex cache indexing)'. policy
    is the write policy. line is the cache Line size in bytes.

    For example, the following options describe 2 NUMA nodes. Node 0 has
    2 cpus and a ram, node 1 has only a ram. The processors in node 0
    access memory in node 0 with access-latency 5 nanoseconds,
    access-bandwidth is 200 MB/s; The processors in NUMA node 0 access
    memory in NUMA node 1 with access-latency 10 nanoseconds,
    access-bandwidth is 100 MB/s. And for memory side cache information,
    NUMA node 0 and 1 both have 1 level memory cache, size is 10KB,
    policy is write-back, the cache Line size is 8 bytes:

    ::

        -machine hmat=on \
        -m 2G \
        -object memory-backend-ram,size=1G,id=m0 \
        -object memory-backend-ram,size=1G,id=m1 \
        -smp 2,sockets=2,maxcpus=2 \
        -numa node,nodeid=0,memdev=m0 \
        -numa node,nodeid=1,memdev=m1,initiator=0 \
        -numa cpu,node-id=0,socket-id=0 \
        -numa cpu,node-id=0,socket-id=1 \
        -numa hmat-lb,initiator=0,target=0,hierarchy=memory,data-type=access-latency,latency=5 \
        -numa hmat-lb,initiator=0,target=0,hierarchy=memory,data-type=access-bandwidth,bandwidth=200M \
        -numa hmat-lb,initiator=0,target=1,hierarchy=memory,data-type=access-latency,latency=10 \
        -numa hmat-lb,initiator=0,target=1,hierarchy=memory,data-type=access-bandwidth,bandwidth=100M \
        -numa hmat-cache,node-id=0,size=10K,level=1,associativity=direct,policy=write-back,line=8 \
        -numa hmat-cache,node-id=1,size=10K,level=1,associativity=direct,policy=write-back,line=8
ERST

DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd,
    "-add-fd fd=fd,set=set[,opaque=opaque]\n"
    "                Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL)
SRST
``-add-fd fd=fd,set=set[,opaque=opaque]``
    Add a file descriptor to an fd set. Valid options are:

    ``fd=fd``
        This option defines the file descriptor of which a duplicate is
        added to fd set. The file descriptor cannot be stdin, stdout, or
        stderr.

    ``set=set``
        This option defines the ID of the fd set to add the file
        descriptor to.

    ``opaque=opaque``
        This option defines a free-form string that can be used to
        describe fd.

    You can open an image using pre-opened file descriptors from an fd
    set:

    .. parsed-literal::

        |qemu_system| \\
         -add-fd fd=3,set=2,opaque="rdwr:/path/to/file" \\
         -add-fd fd=4,set=2,opaque="rdonly:/path/to/file" \\
         -drive file=/dev/fdset/2,index=0,media=disk
ERST

DEF("set", HAS_ARG, QEMU_OPTION_set,
    "-set group.id.arg=value\n"
    "                set <arg> parameter for item <id> of type <group>\n"
    "                i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL)
SRST
``-set group.id.arg=value``
    Set parameter arg for item id of type group
ERST

DEF("global", HAS_ARG, QEMU_OPTION_global,
    "-global driver.property=value\n"
    "-global driver=driver,property=property,value=value\n"
    "                set a global default for a driver property\n",
    QEMU_ARCH_ALL)
SRST
``-global driver.prop=value``
  \ 
``-global driver=driver,property=property,value=value``
    Set default value of driver's property prop to value, e.g.:

    .. parsed-literal::

        |qemu_system_x86| -global ide-hd.physical_block_size=4096 disk-image.img

    In particular, you can use this to set driver properties for devices
    which are created automatically by the machine model. To create a
    device which is not created automatically and set properties on it,
    use -``device``.

    -global driver.prop=value is shorthand for -global
    driver=driver,property=prop,value=value. The longhand syntax works
    even when driver contains a dot.
ERST

DEF("boot", HAS_ARG, QEMU_OPTION_boot,
    "-boot [order=drives][,once=drives][,menu=on|off]\n"
    "      [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n"
    "                'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n"
    "                'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n"
    "                'sp_time': the period that splash picture last if menu=on, unit is ms\n"
    "                'rb_timeout': the timeout before guest reboot when boot failed, unit is ms\n",
    QEMU_ARCH_ALL)
SRST
``-boot [order=drives][,once=drives][,menu=on|off][,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_timeout][,strict=on|off]``
    Specify boot order drives as a string of drive letters. Valid drive
    letters depend on the target architecture. The x86 PC uses: a, b
    (floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p
    (Etherboot from network adapter 1-4), hard disk boot is the default.
    To apply a particular boot order only on the first startup, specify
    it via ``once``. Note that the ``order`` or ``once`` parameter
    should not be used together with the ``bootindex`` property of
    devices, since the firmware implementations normally do not support
    both at the same time.

    Interactive boot menus/prompts can be enabled via ``menu=on`` as far
    as firmware/BIOS supports them. The default is non-interactive boot.

    A splash picture could be passed to bios, enabling user to show it
    as logo, when option splash=sp\_name is given and menu=on, If
    firmware/BIOS supports them. Currently Seabios for X86 system
    support it. limitation: The splash file could be a jpeg file or a
    BMP file in 24 BPP format(true color). The resolution should be
    supported by the SVGA mode, so the recommended is 320x240, 640x480,
    800x640.

    A timeout could be passed to bios, guest will pause for rb\_timeout
    ms when boot failed, then reboot. If rb\_timeout is '-1', guest will
    not reboot, qemu passes '-1' to bios by default. Currently Seabios
    for X86 system support it.

    Do strict boot via ``strict=on`` as far as firmware/BIOS supports
    it. This only effects when boot priority is changed by bootindex
    options. The default is non-strict boot.

    .. parsed-literal::

        # try to boot from network first, then from hard disk
        |qemu_system_x86| -boot order=nc
        # boot from CD-ROM first, switch back to default order after reboot
        |qemu_system_x86| -boot once=d
        # boot with a splash picture for 5 seconds.
        |qemu_system_x86| -boot menu=on,splash=/root/boot.bmp,splash-time=5000

    Note: The legacy format '-boot drives' is still supported but its
    use is discouraged as it may be removed from future versions.
ERST

DEF("m", HAS_ARG, QEMU_OPTION_m,
    "-m [size=]megs[,slots=n,maxmem=size]\n"
    "                configure guest RAM\n"
    "                size: initial amount of guest memory\n"
    "                slots: number of hotplug slots (default: none)\n"
    "                maxmem: maximum amount of guest memory (default: none)\n"
    "NOTE: Some architectures might enforce a specific granularity\n",
    QEMU_ARCH_ALL)
SRST
``-m [size=]megs[,slots=n,maxmem=size]``
    Sets guest startup RAM size to megs megabytes. Default is 128 MiB.
    Optionally, a suffix of "M" or "G" can be used to signify a value in
    megabytes or gigabytes respectively. Optional pair slots, maxmem
    could be used to set amount of hotpluggable memory slots and maximum
    amount of memory. Note that maxmem must be aligned to the page size.

    For example, the following command-line sets the guest startup RAM
    size to 1GB, creates 3 slots to hotplug additional memory and sets
    the maximum memory the guest can reach to 4GB:

    .. parsed-literal::

        |qemu_system| -m 1G,slots=3,maxmem=4G

    If slots and maxmem are not specified, memory hotplug won't be
    enabled and the guest startup RAM will never increase.
ERST

DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath,
    "-mem-path FILE  provide backing storage for guest RAM\n", QEMU_ARCH_ALL)
SRST
``-mem-path path``
    Allocate guest RAM from a temporarily created file in path.
ERST

DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc,
    "-mem-prealloc   preallocate guest memory (use with -mem-path)\n",
    QEMU_ARCH_ALL)
SRST
``-mem-prealloc``
    Preallocate memory when using -mem-path.
ERST

DEF("k", HAS_ARG, QEMU_OPTION_k,
    "-k language     use keyboard layout (for example 'fr' for French)\n",
    QEMU_ARCH_ALL)
SRST
``-k language``
    Use keyboard layout language (for example ``fr`` for French). This
    option is only needed where it is not easy to get raw PC keycodes
    (e.g. on Macs, with some X11 servers or with a VNC or curses
    display). You don't normally need to use it on PC/Linux or
    PC/Windows hosts.

    The available layouts are:

    ::

        ar  de-ch  es  fo     fr-ca  hu  ja  mk     no  pt-br  sv
        da  en-gb  et  fr     fr-ch  is  lt  nl     pl  ru     th
        de  en-us  fi  fr-be  hr     it  lv  nl-be  pt  sl     tr

    The default is ``en-us``.
ERST


HXCOMM Deprecated by -audiodev
DEF("audio-help", 0, QEMU_OPTION_audio_help,
    "-audio-help     show -audiodev equivalent of the currently specified audio settings\n",
    QEMU_ARCH_ALL)
SRST
``-audio-help``
    Will show the -audiodev equivalent of the currently specified
    (deprecated) environment variables.
ERST

DEF("audiodev", HAS_ARG, QEMU_OPTION_audiodev,
    "-audiodev [driver=]driver,id=id[,prop[=value][,...]]\n"
    "                specifies the audio backend to use\n"
    "                id= identifier of the backend\n"
    "                timer-period= timer period in microseconds\n"
    "                in|out.mixing-engine= use mixing engine to mix streams inside QEMU\n"
    "                in|out.fixed-settings= use fixed settings for host audio\n"
    "                in|out.frequency= frequency to use with fixed settings\n"
    "                in|out.channels= number of channels to use with fixed settings\n"
    "                in|out.format= sample format to use with fixed settings\n"
    "                valid values: s8, s16, s32, u8, u16, u32, f32\n"
    "                in|out.voices= number of voices to use\n"
    "                in|out.buffer-length= length of buffer in microseconds\n"
    "-audiodev none,id=id,[,prop[=value][,...]]\n"
    "                dummy driver that discards all output\n"
#ifdef CONFIG_AUDIO_ALSA
    "-audiodev alsa,id=id[,prop[=value][,...]]\n"
    "                in|out.dev= name of the audio device to use\n"
    "                in|out.period-length= length of period in microseconds\n"
    "                in|out.try-poll= attempt to use poll mode\n"
    "                threshold= threshold (in microseconds) when playback starts\n"
#endif
#ifdef CONFIG_AUDIO_COREAUDIO
    "-audiodev coreaudio,id=id[,prop[=value][,...]]\n"
    "                in|out.buffer-count= number of buffers\n"
#endif
#ifdef CONFIG_AUDIO_DSOUND
    "-audiodev dsound,id=id[,prop[=value][,...]]\n"
    "                latency= add extra latency to playback in microseconds\n"
#endif
#ifdef CONFIG_AUDIO_OSS
    "-audiodev oss,id=id[,prop[=value][,...]]\n"
    "                in|out.dev= path of the audio device to use\n"
    "                in|out.buffer-count= number of buffers\n"
    "                in|out.try-poll= attempt to use poll mode\n"
    "                try-mmap= try using memory mapped access\n"
    "                exclusive= open device in exclusive mode\n"
    "                dsp-policy= set timing policy (0..10), -1 to use fragment mode\n"
#endif
#ifdef CONFIG_AUDIO_PA
    "-audiodev pa,id=id[,prop[=value][,...]]\n"
    "                server= PulseAudio server address\n"
    "                in|out.name= source/sink device name\n"
    "                in|out.latency= desired latency in microseconds\n"
#endif
#ifdef CONFIG_AUDIO_SDL
    "-audiodev sdl,id=id[,prop[=value][,...]]\n"
    "                in|out.buffer-count= number of buffers\n"
#endif
#ifdef CONFIG_SPICE
    "-audiodev spice,id=id[,prop[=value][,...]]\n"
#endif
    "-audiodev wav,id=id[,prop[=value][,...]]\n"
    "                path= path of wav file to record\n",
    QEMU_ARCH_ALL)
SRST
``-audiodev [driver=]driver,id=id[,prop[=value][,...]]``
    Adds a new audio backend driver identified by id. There are global
    and driver specific properties. Some values can be set differently
    for input and output, they're marked with ``in|out.``. You can set
    the input's property with ``in.prop`` and the output's property with
    ``out.prop``. For example:

    ::

        -audiodev alsa,id=example,in.frequency=44110,out.frequency=8000
        -audiodev alsa,id=example,out.channels=1 # leaves in.channels unspecified

    NOTE: parameter validation is known to be incomplete, in many cases
    specifying an invalid option causes QEMU to print an error message
    and continue emulation without sound.

    Valid global options are:

    ``id=identifier``
        Identifies the audio backend.

    ``timer-period=period``
        Sets the timer period used by the audio subsystem in
        microseconds. Default is 10000 (10 ms).

    ``in|out.mixing-engine=on|off``
        Use QEMU's mixing engine to mix all streams inside QEMU and
        convert audio formats when not supported by the backend. When
        off, fixed-settings must be off too. Note that disabling this
        option means that the selected backend must support multiple
        streams and the audio formats used by the virtual cards,
        otherwise you'll get no sound. It's not recommended to disable
        this option unless you want to use 5.1 or 7.1 audio, as mixing
        engine only supports mono and stereo audio. Default is on.

    ``in|out.fixed-settings=on|off``
        Use fixed settings for host audio. When off, it will change
        based on how the guest opens the sound card. In this case you
        must not specify frequency, channels or format. Default is on.

    ``in|out.frequency=frequency``
        Specify the frequency to use when using fixed-settings. Default
        is 44100Hz.

    ``in|out.channels=channels``
        Specify the number of channels to use when using fixed-settings.
        Default is 2 (stereo).

    ``in|out.format=format``
        Specify the sample format to use when using fixed-settings.
        Valid values are: ``s8``, ``s16``, ``s32``, ``u8``, ``u16``,
        ``u32``, ``f32``. Default is ``s16``.

    ``in|out.voices=voices``
        Specify the number of voices to use. Default is 1.

    ``in|out.buffer-length=usecs``
        Sets the size of the buffer in microseconds.

``-audiodev none,id=id[,prop[=value][,...]]``
    Creates a dummy backend that discards all outputs. This backend has
    no backend specific properties.

``-audiodev alsa,id=id[,prop[=value][,...]]``
    Creates backend using the ALSA. This backend is only available on
    Linux.

    ALSA specific options are:

    ``in|out.dev=device``
        Specify the ALSA device to use for input and/or output. Default
        is ``default``.

    ``in|out.period-length=usecs``
        Sets the period length in microseconds.

    ``in|out.try-poll=on|off``
        Attempt to use poll mode with the device. Default is on.

    ``threshold=threshold``
        Threshold (in microseconds) when playback starts. Default is 0.

``-audiodev coreaudio,id=id[,prop[=value][,...]]``
    Creates a backend using Apple's Core Audio. This backend is only
    available on Mac OS and only supports playback.

    Core Audio specific options are:

    ``in|out.buffer-count=count``
        Sets the count of the buffers.

``-audiodev dsound,id=id[,prop[=value][,...]]``
    Creates a backend using Microsoft's DirectSound. This backend is
    only available on Windows and only supports playback.

    DirectSound specific options are:

    ``latency=usecs``
        Add extra usecs microseconds latency to playback. Default is
        10000 (10 ms).

``-audiodev oss,id=id[,prop[=value][,...]]``
    Creates a backend using OSS. This backend is available on most
    Unix-like systems.

    OSS specific options are:

    ``in|out.dev=device``
        Specify the file name of the OSS device to use. Default is
        ``/dev/dsp``.

    ``in|out.buffer-count=count``
        Sets the count of the buffers.

    ``in|out.try-poll=on|of``
        Attempt to use poll mode with the device. Default is on.

    ``try-mmap=on|off``
        Try using memory mapped device access. Default is off.

    ``exclusive=on|off``
        Open the device in exclusive mode (vmix won't work in this
        case). Default is off.

    ``dsp-policy=policy``
        Sets the timing policy (between 0 and 10, where smaller number
        means smaller latency but higher CPU usage). Use -1 to use
        buffer sizes specified by ``buffer`` and ``buffer-count``. This
        option is ignored if you do not have OSS 4. Default is 5.

``-audiodev pa,id=id[,prop[=value][,...]]``
    Creates a backend using PulseAudio. This backend is available on
    most systems.

    PulseAudio specific options are:

    ``server=server``
        Sets the PulseAudio server to connect to.

    ``in|out.name=sink``
        Use the specified source/sink for recording/playback.

    ``in|out.latency=usecs``
        Desired latency in microseconds. The PulseAudio server will try
        to honor this value but actual latencies may be lower or higher.

``-audiodev sdl,id=id[,prop[=value][,...]]``
    Creates a backend using SDL. This backend is available on most
    systems, but you should use your platform's native backend if
    possible.

    SDL specific options are:

    ``in|out.buffer-count=count``
        Sets the count of the buffers.

``-audiodev spice,id=id[,prop[=value][,...]]``
    Creates a backend that sends audio through SPICE. This backend
    requires ``-spice`` and automatically selected in that case, so
    usually you can ignore this option. This backend has no backend
    specific properties.

``-audiodev wav,id=id[,prop[=value][,...]]``
    Creates a backend that writes audio to a WAV file.

    Backend specific options are:

    ``path=path``
        Write recorded audio into the specified file. Default is
        ``qemu.wav``.
ERST

DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw,
    "-soundhw c1,... enable audio support\n"
    "                and only specified sound cards (comma separated list)\n"
    "                use '-soundhw help' to get the list of supported cards\n"
    "                use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL)
SRST
``-soundhw card1[,card2,...] or -soundhw all``
    Enable audio and selected sound hardware. Use 'help' to print all
    available sound hardware. For example:

    .. parsed-literal::

        |qemu_system_x86| -soundhw sb16,adlib disk.img
        |qemu_system_x86| -soundhw es1370 disk.img
        |qemu_system_x86| -soundhw ac97 disk.img
        |qemu_system_x86| -soundhw hda disk.img
        |qemu_system_x86| -soundhw all disk.img
        |qemu_system_x86| -soundhw help

    Note that Linux's i810\_audio OSS kernel (for AC97) module might
    require manually specifying clocking.

    ::

        modprobe i810_audio clocking=48000
ERST

DEF("device", HAS_ARG, QEMU_OPTION_device,
    "-device driver[,prop[=value][,...]]\n"
    "                add device (based on driver)\n"
    "                prop=value,... sets driver properties\n"
    "                use '-device help' to print all possible drivers\n"
    "                use '-device driver,help' to print all possible properties\n",
    QEMU_ARCH_ALL)
SRST
``-device driver[,prop[=value][,...]]``
    Add device driver. prop=value sets driver properties. Valid
    properties depend on the driver. To get help on possible drivers and
    properties, use ``-device help`` and ``-device driver,help``.

    Some drivers are:

``-device ipmi-bmc-sim,id=id[,prop[=value][,...]]``
    Add an IPMI BMC. This is a simulation of a hardware management
    interface processor that normally sits on a system. It provides a
    watchdog and the ability to reset and power control the system. You
    need to connect this to an IPMI interface to make it useful

    The IPMI slave address to use for the BMC. The default is 0x20. This
    address is the BMC's address on the I2C network of management
    controllers. If you don't know what this means, it is safe to ignore
    it.

    ``id=id``
        The BMC id for interfaces to use this device.

    ``slave_addr=val``
        Define slave address to use for the BMC. The default is 0x20.

    ``sdrfile=file``
        file containing raw Sensor Data Records (SDR) data. The default
        is none.

    ``fruareasize=val``
        size of a Field Replaceable Unit (FRU) area. The default is
        1024.

    ``frudatafile=file``
        file containing raw Field Replaceable Unit (FRU) inventory data.
        The default is none.

    ``guid=uuid``
        value for the GUID for the BMC, in standard UUID format. If this
        is set, get "Get GUID" command to the BMC will return it.
        Otherwise "Get GUID" will return an error.

``-device ipmi-bmc-extern,id=id,chardev=id[,slave_addr=val]``
    Add a connection to an external IPMI BMC simulator. Instead of
    locally emulating the BMC like the above item, instead connect to an
    external entity that provides the IPMI services.

    A connection is made to an external BMC simulator. If you do this,
    it is strongly recommended that you use the "reconnect=" chardev
    option to reconnect to the simulator if the connection is lost. Note
    that if this is not used carefully, it can be a security issue, as
    the interface has the ability to send resets, NMIs, and power off
    the VM. It's best if QEMU makes a connection to an external
    simulator running on a secure port on localhost, so neither the
    simulator nor QEMU is exposed to any outside network.

    See the "lanserv/README.vm" file in the OpenIPMI library for more
    details on the external interface.

``-device isa-ipmi-kcs,bmc=id[,ioport=val][,irq=val]``
    Add a KCS IPMI interafce on the ISA bus. This also adds a
    corresponding ACPI and SMBIOS entries, if appropriate.

    ``bmc=id``
        The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern
        above.

    ``ioport=val``
        Define the I/O address of the interface. The default is 0xca0
        for KCS.

    ``irq=val``
        Define the interrupt to use. The default is 5. To disable
        interrupts, set this to 0.

``-device isa-ipmi-bt,bmc=id[,ioport=val][,irq=val]``
    Like the KCS interface, but defines a BT interface. The default port
    is 0xe4 and the default interrupt is 5.

``-device pci-ipmi-kcs,bmc=id``
    Add a KCS IPMI interafce on the PCI bus.

    ``bmc=id``
        The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above.

``-device pci-ipmi-bt,bmc=id``
    Like the KCS interface, but defines a BT interface on the PCI bus.

``-device intel-iommu[,option=...]``
    This is only supported by ``-machine q35``, which will enable Intel VT-d
    emulation within the guest.  It supports below options:

    ``intremap=on|off`` (default: auto)
        This enables interrupt remapping feature.  It's required to enable
        complete x2apic.  Currently it only supports kvm kernel-irqchip modes
        ``off`` or ``split``, while full kernel-irqchip is not yet supported.
        The default value is "auto", which will be decided by the mode of
        kernel-irqchip.

    ``caching-mode=on|off`` (default: off)
        This enables caching mode for the VT-d emulated device.  When
        caching-mode is enabled, each guest DMA buffer mapping will generate an
        IOTLB invalidation from the guest IOMMU driver to the vIOMMU device in
        a synchronous way.  It is required for ``-device vfio-pci`` to work
        with the VT-d device, because host assigned devices requires to setup
        the DMA mapping on the host before guest DMA starts.

    ``device-iotlb=on|off`` (default: off)
        This enables device-iotlb capability for the emulated VT-d device.  So
        far virtio/vhost should be the only real user for this parameter,
        paired with ats=on configured for the device.

    ``aw-bits=39|48`` (default: 39)
        This decides the address width of IOVA address space.  The address
        space has 39 bits width for 3-level IOMMU page tables, and 48 bits for
        4-level IOMMU page tables.

    Please also refer to the wiki page for general scenarios of VT-d
    emulation in QEMU: https://wiki.qemu.org/Features/VT-d.

ERST

DEF("name", HAS_ARG, QEMU_OPTION_name,
    "-name string1[,process=string2][,debug-threads=on|off]\n"
    "                set the name of the guest\n"
    "                string1 sets the window title and string2 the process name\n"
    "                When debug-threads is enabled, individual threads are given a separate name\n"
    "                NOTE: The thread names are for debugging and not a stable API.\n",
    QEMU_ARCH_ALL)
SRST
``-name name``
    Sets the name of the guest. This name will be displayed in the SDL
    window caption. The name will also be used for the VNC server. Also
    optionally set the top visible process name in Linux. Naming of
    individual threads can also be enabled on Linux to aid debugging.
ERST

DEF("uuid", HAS_ARG, QEMU_OPTION_uuid,
    "-uuid %08x-%04x-%04x-%04x-%012x\n"
    "                specify machine UUID\n", QEMU_ARCH_ALL)
SRST
``-uuid uuid``
    Set system UUID.
ERST

DEFHEADING()

DEFHEADING(Block device options:)

DEF("fda", HAS_ARG, QEMU_OPTION_fda,
    "-fda/-fdb file  use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL)
DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL)
SRST
``-fda file``
  \
``-fdb file``
    Use file as floppy disk 0/1 image (see the :ref:`disk images` chapter in
    the System Emulation Users Guide).
ERST

DEF("hda", HAS_ARG, QEMU_OPTION_hda,
    "-hda/-hdb file  use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL)
DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL)
DEF("hdc", HAS_ARG, QEMU_OPTION_hdc,
    "-hdc/-hdd file  use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL)
DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL)
SRST
``-hda file``
  \
``-hdb file``
  \ 
``-hdc file``
  \ 
``-hdd file``
    Use file as hard disk 0, 1, 2 or 3 image (see the :ref:`disk images`
    chapter in the System Emulation Users Guide).
ERST

DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom,
    "-cdrom file     use 'file' as IDE cdrom image (cdrom is ide1 master)\n",
    QEMU_ARCH_ALL)
SRST
``-cdrom file``
    Use file as CD-ROM image (you cannot use ``-hdc`` and ``-cdrom`` at
    the same time). You can use the host CD-ROM by using ``/dev/cdrom``
    as filename.
ERST

DEF("blockdev", HAS_ARG, QEMU_OPTION_blockdev,
    "-blockdev [driver=]driver[,node-name=N][,discard=ignore|unmap]\n"
    "          [,cache.direct=on|off][,cache.no-flush=on|off]\n"
    "          [,read-only=on|off][,auto-read-only=on|off]\n"
    "          [,force-share=on|off][,detect-zeroes=on|off|unmap]\n"
    "          [,driver specific parameters...]\n"
    "                configure a block backend\n", QEMU_ARCH_ALL)
SRST
``-blockdev option[,option[,option[,...]]]``
    Define a new block driver node. Some of the options apply to all
    block drivers, other options are only accepted for a specific block
    driver. See below for a list of generic options and options for the
    most common block drivers.

    Options that expect a reference to another node (e.g. ``file``) can
    be given in two ways. Either you specify the node name of an already
    existing node (file=node-name), or you define a new node inline,
    adding options for the referenced node after a dot
    (file.filename=path,file.aio=native).

    A block driver node created with ``-blockdev`` can be used for a
    guest device by specifying its node name for the ``drive`` property
    in a ``-device`` argument that defines a block device.

    ``Valid options for any block driver node:``
        ``driver``
            Specifies the block driver to use for the given node.

        ``node-name``
            This defines the name of the block driver node by which it
            will be referenced later. The name must be unique, i.e. it
            must not match the name of a different block driver node, or
            (if you use ``-drive`` as well) the ID of a drive.

            If no node name is specified, it is automatically generated.
            The generated node name is not intended to be predictable
            and changes between QEMU invocations. For the top level, an
            explicit node name must be specified.

        ``read-only``
            Open the node read-only. Guest write attempts will fail.

            Note that some block drivers support only read-only access,
            either generally or in certain configurations. In this case,
            the default value ``read-only=off`` does not work and the
            option must be specified explicitly.

        ``auto-read-only``
            If ``auto-read-only=on`` is set, QEMU may fall back to
            read-only usage even when ``read-only=off`` is requested, or
            even switch between modes as needed, e.g. depending on
            whether the image file is writable or whether a writing user
            is attached to the node.

        ``force-share``
            Override the image locking system of QEMU by forcing the
            node to utilize weaker shared access for permissions where
            it would normally request exclusive access. When there is
            the potential for multiple instances to have the same file
            open (whether this invocation of QEMU is the first or the
            second instance), both instances must permit shared access
            for the second instance to succeed at opening the file.

            Enabling ``force-share=on`` requires ``read-only=on``.

        ``cache.direct``
            The host page cache can be avoided with ``cache.direct=on``.
            This will attempt to do disk IO directly to the guest's
            memory. QEMU may still perform an internal copy of the data.

        ``cache.no-flush``
            In case you don't care about data integrity over host
            failures, you can use ``cache.no-flush=on``. This option
            tells QEMU that it never needs to write any data to the disk
            but can instead keep things in cache. If anything goes
            wrong, like your host losing power, the disk storage getting
            disconnected accidentally, etc. your image will most
            probably be rendered unusable.

        ``discard=discard``
            discard is one of "ignore" (or "off") or "unmap" (or "on")
            and controls whether ``discard`` (also known as ``trim`` or
            ``unmap``) requests are ignored or passed to the filesystem.
            Some machine types may not support discard requests.

        ``detect-zeroes=detect-zeroes``
            detect-zeroes is "off", "on" or "unmap" and enables the
            automatic conversion of plain zero writes by the OS to
            driver specific optimized zero write commands. You may even
            choose "unmap" if discard is set to "unmap" to allow a zero
            write to be converted to an ``unmap`` operation.

    ``Driver-specific options for file``
        This is the protocol-level block driver for accessing regular
        files.

        ``filename``
            The path to the image file in the local filesystem

        ``aio``
            Specifies the AIO backend (threads/native/io_uring,
            default: threads)

        ``locking``
            Specifies whether the image file is protected with Linux OFD
            / POSIX locks. The default is to use the Linux Open File
            Descriptor API if available, otherwise no lock is applied.
            (auto/on/off, default: auto)

        Example:

        ::

            -blockdev driver=file,node-name=disk,filename=disk.img

    ``Driver-specific options for raw``
        This is the image format block driver for raw images. It is
        usually stacked on top of a protocol level block driver such as
        ``file``.

        ``file``
            Reference to or definition of the data source block driver
            node (e.g. a ``file`` driver node)

        Example 1:

        ::

            -blockdev driver=file,node-name=disk_file,filename=disk.img
            -blockdev driver=raw,node-name=disk,file=disk_file

        Example 2:

        ::

            -blockdev driver=raw,node-name=disk,file.driver=file,file.filename=disk.img

    ``Driver-specific options for qcow2``
        This is the image format block driver for qcow2 images. It is
        usually stacked on top of a protocol level block driver such as
        ``file``.

        ``file``
            Reference to or definition of the data source block driver
            node (e.g. a ``file`` driver node)

        ``backing``
            Reference to or definition of the backing file block device
            (default is taken from the image file). It is allowed to
            pass ``null`` here in order to disable the default backing
            file.

        ``lazy-refcounts``
            Whether to enable the lazy refcounts feature (on/off;
            default is taken from the image file)

        ``cache-size``
            The maximum total size of the L2 table and refcount block
            caches in bytes (default: the sum of l2-cache-size and
            refcount-cache-size)

        ``l2-cache-size``
            The maximum size of the L2 table cache in bytes (default: if
            cache-size is not specified - 32M on Linux platforms, and 8M
            on non-Linux platforms; otherwise, as large as possible
            within the cache-size, while permitting the requested or the
            minimal refcount cache size)

        ``refcount-cache-size``
            The maximum size of the refcount block cache in bytes
            (default: 4 times the cluster size; or if cache-size is
            specified, the part of it which is not used for the L2
            cache)

        ``cache-clean-interval``
            Clean unused entries in the L2 and refcount caches. The
            interval is in seconds. The default value is 600 on
            supporting platforms, and 0 on other platforms. Setting it
            to 0 disables this feature.

        ``pass-discard-request``
            Whether discard requests to the qcow2 device should be
            forwarded to the data source (on/off; default: on if
            discard=unmap is specified, off otherwise)

        ``pass-discard-snapshot``
            Whether discard requests for the data source should be
            issued when a snapshot operation (e.g. deleting a snapshot)
            frees clusters in the qcow2 file (on/off; default: on)

        ``pass-discard-other``
            Whether discard requests for the data source should be
            issued on other occasions where a cluster gets freed
            (on/off; default: off)

        ``overlap-check``
            Which overlap checks to perform for writes to the image
            (none/constant/cached/all; default: cached). For details or
            finer granularity control refer to the QAPI documentation of
            ``blockdev-add``.

        Example 1:

        ::

            -blockdev driver=file,node-name=my_file,filename=/tmp/disk.qcow2
            -blockdev driver=qcow2,node-name=hda,file=my_file,overlap-check=none,cache-size=16777216

        Example 2:

        ::

            -blockdev driver=qcow2,node-name=disk,file.driver=http,file.filename=http://example.com/image.qcow2

    ``Driver-specific options for other drivers``
        Please refer to the QAPI documentation of the ``blockdev-add``
        QMP command.
ERST

DEF("drive", HAS_ARG, QEMU_OPTION_drive,
    "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n"
    "       [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n"
    "       [,snapshot=on|off][,rerror=ignore|stop|report]\n"
    "       [,werror=ignore|stop|report|enospc][,id=name]\n"
    "       [,aio=threads|native|io_uring]\n"
    "       [,readonly=on|off][,copy-on-read=on|off]\n"
    "       [,discard=ignore|unmap][,detect-zeroes=on|off|unmap]\n"
    "       [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n"
    "       [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n"
    "       [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n"
    "       [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n"
    "       [[,iops_size=is]]\n"
    "       [[,group=g]]\n"
    "                use 'file' as a drive image\n", QEMU_ARCH_ALL)
SRST
``-drive option[,option[,option[,...]]]``
    Define a new drive. This includes creating a block driver node (the
    backend) as well as a guest device, and is mostly a shortcut for
    defining the corresponding ``-blockdev`` and ``-device`` options.

    ``-drive`` accepts all options that are accepted by ``-blockdev``.
    In addition, it knows the following options:

    ``file=file``
        This option defines which disk image (see the :ref:`disk images`
        chapter in the System Emulation Users Guide) to use with this drive.
        If the filename contains comma, you must double it (for instance,
        "file=my,,file" to use file "my,file").

        Special files such as iSCSI devices can be specified using
        protocol specific URLs. See the section for "Device URL Syntax"
        for more information.

    ``if=interface``
        This option defines on which type on interface the drive is
        connected. Available types are: ide, scsi, sd, mtd, floppy,
        pflash, virtio, none.

    ``bus=bus,unit=unit``
        These options define where is connected the drive by defining
        the bus number and the unit id.

    ``index=index``
        This option defines where is connected the drive by using an
        index in the list of available connectors of a given interface
        type.

    ``media=media``
        This option defines the type of the media: disk or cdrom.

    ``snapshot=snapshot``
        snapshot is "on" or "off" and controls snapshot mode for the
        given drive (see ``-snapshot``).

    ``cache=cache``
        cache is "none", "writeback", "unsafe", "directsync" or
        "writethrough" and controls how the host cache is used to access
        block data. This is a shortcut that sets the ``cache.direct``
        and ``cache.no-flush`` options (as in ``-blockdev``), and
        additionally ``cache.writeback``, which provides a default for
        the ``write-cache`` option of block guest devices (as in
        ``-device``). The modes correspond to the following settings:

        =============  ===============   ============   ==============
        \              cache.writeback   cache.direct   cache.no-flush
        =============  ===============   ============   ==============
        writeback      on                off            off
        none           on                on             off
        writethrough   off               off            off
        directsync     off               on             off
        unsafe         on                off            on
        =============  ===============   ============   ==============

        The default mode is ``cache=writeback``.

    ``aio=aio``
        aio is "threads", "native", or "io_uring" and selects between pthread
        based disk I/O, native Linux AIO, or Linux io_uring API.

    ``format=format``
        Specify which disk format will be used rather than detecting the
        format. Can be used to specify format=raw to avoid interpreting
        an untrusted format header.

    ``werror=action,rerror=action``
        Specify which action to take on write and read errors. Valid
        actions are: "ignore" (ignore the error and try to continue),
        "stop" (pause QEMU), "report" (report the error to the guest),
        "enospc" (pause QEMU only if the host disk is full; report the
        error to the guest otherwise). The default setting is
        ``werror=enospc`` and ``rerror=report``.

    ``copy-on-read=copy-on-read``
        copy-on-read is "on" or "off" and enables whether to copy read
        backing file sectors into the image file.

    ``bps=b,bps_rd=r,bps_wr=w``
        Specify bandwidth throttling limits in bytes per second, either
        for all request types or for reads or writes only. Small values
        can lead to timeouts or hangs inside the guest. A safe minimum
        for disks is 2 MB/s.

    ``bps_max=bm,bps_rd_max=rm,bps_wr_max=wm``
        Specify bursts in bytes per second, either for all request types
        or for reads or writes only. Bursts allow the guest I/O to spike
        above the limit temporarily.

    ``iops=i,iops_rd=r,iops_wr=w``
        Specify request rate limits in requests per second, either for
        all request types or for reads or writes only.

    ``iops_max=bm,iops_rd_max=rm,iops_wr_max=wm``
        Specify bursts in requests per second, either for all request
        types or for reads or writes only. Bursts allow the guest I/O to
        spike above the limit temporarily.

    ``iops_size=is``
        Let every is bytes of a request count as a new request for iops
        throttling purposes. Use this option to prevent guests from
        circumventing iops limits by sending fewer but larger requests.

    ``group=g``
        Join a throttling quota group with given name g. All drives that
        are members of the same group are accounted for together. Use
        this option to prevent guests from circumventing throttling
        limits by using many small disks instead of a single larger
        disk.

    By default, the ``cache.writeback=on`` mode is used. It will report
    data writes as completed as soon as the data is present in the host
    page cache. This is safe as long as your guest OS makes sure to
    correctly flush disk caches where needed. If your guest OS does not
    handle volatile disk write caches correctly and your host crashes or
    loses power, then the guest may experience data corruption.

    For such guests, you should consider using ``cache.writeback=off``.
    This means that the host page cache will be used to read and write
    data, but write notification will be sent to the guest only after
    QEMU has made sure to flush each write to the disk. Be aware that
    this has a major impact on performance.

    When using the ``-snapshot`` option, unsafe caching is always used.

    Copy-on-read avoids accessing the same backing file sectors
    repeatedly and is useful when the backing file is over a slow
    network. By default copy-on-read is off.

    Instead of ``-cdrom`` you can use:

    .. parsed-literal::

        |qemu_system| -drive file=file,index=2,media=cdrom

    Instead of ``-hda``, ``-hdb``, ``-hdc``, ``-hdd``, you can use:

    .. parsed-literal::

        |qemu_system| -drive file=file,index=0,media=disk
        |qemu_system| -drive file=file,index=1,media=disk
        |qemu_system| -drive file=file,index=2,media=disk
        |qemu_system| -drive file=file,index=3,media=disk

    You can open an image using pre-opened file descriptors from an fd
    set:

    .. parsed-literal::

        |qemu_system| \\
         -add-fd fd=3,set=2,opaque="rdwr:/path/to/file" \\
         -add-fd fd=4,set=2,opaque="rdonly:/path/to/file" \\
         -drive file=/dev/fdset/2,index=0,media=disk

    You can connect a CDROM to the slave of ide0:

    .. parsed-literal::

        |qemu_system_x86| -drive file=file,if=ide,index=1,media=cdrom

    If you don't specify the "file=" argument, you define an empty
    drive:

    .. parsed-literal::

        |qemu_system_x86| -drive if=ide,index=1,media=cdrom

    Instead of ``-fda``, ``-fdb``, you can use:

    .. parsed-literal::

        |qemu_system_x86| -drive file=file,index=0,if=floppy
        |qemu_system_x86| -drive file=file,index=1,if=floppy

    By default, interface is "ide" and index is automatically
    incremented:

    .. parsed-literal::

        |qemu_system_x86| -drive file=a -drive file=b"

    is interpreted like:

    .. parsed-literal::

        |qemu_system_x86| -hda a -hdb b
ERST

DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock,
    "-mtdblock file  use 'file' as on-board Flash memory image\n",
    QEMU_ARCH_ALL)
SRST
``-mtdblock file``
    Use file as on-board Flash memory image.
ERST

DEF("sd", HAS_ARG, QEMU_OPTION_sd,
    "-sd file        use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL)
SRST
``-sd file``
    Use file as SecureDigital card image.
ERST

DEF("pflash", HAS_ARG, QEMU_OPTION_pflash,
    "-pflash file    use 'file' as a parallel flash image\n", QEMU_ARCH_ALL)
SRST
``-pflash file``
    Use file as a parallel flash image.
ERST

DEF("snapshot", 0, QEMU_OPTION_snapshot,
    "-snapshot       write to temporary files instead of disk image files\n",
    QEMU_ARCH_ALL)
SRST
``-snapshot``
    Write to temporary files instead of disk image files. In this case,
    the raw disk image you use is not written back. You can however
    force the write back by pressing C-a s (see the :ref:`disk images`
    chapter in the System Emulation Users Guide).
ERST

DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev,
    "-fsdev local,id=id,path=path,security_model=mapped-xattr|mapped-file|passthrough|none\n"
    " [,writeout=immediate][,readonly=on][,fmode=fmode][,dmode=dmode]\n"
    " [[,throttling.bps-total=b]|[[,throttling.bps-read=r][,throttling.bps-write=w]]]\n"
    " [[,throttling.iops-total=i]|[[,throttling.iops-read=r][,throttling.iops-write=w]]]\n"
    " [[,throttling.bps-total-max=bm]|[[,throttling.bps-read-max=rm][,throttling.bps-write-max=wm]]]\n"
    " [[,throttling.iops-total-max=im]|[[,throttling.iops-read-max=irm][,throttling.iops-write-max=iwm]]]\n"
    " [[,throttling.iops-size=is]]\n"
    "-fsdev proxy,id=id,socket=socket[,writeout=immediate][,readonly=on]\n"
    "-fsdev proxy,id=id,sock_fd=sock_fd[,writeout=immediate][,readonly=on]\n"
    "-fsdev synth,id=id\n",
    QEMU_ARCH_ALL)

SRST
``-fsdev local,id=id,path=path,security_model=security_model [,writeout=writeout][,readonly=on][,fmode=fmode][,dmode=dmode] [,throttling.option=value[,throttling.option=value[,...]]]``
  \ 
``-fsdev proxy,id=id,socket=socket[,writeout=writeout][,readonly=on]``
  \
``-fsdev proxy,id=id,sock_fd=sock_fd[,writeout=writeout][,readonly=on]``
  \
``-fsdev synth,id=id[,readonly=on]``
    Define a new file system device. Valid options are:

    ``local``
        Accesses to the filesystem are done by QEMU.

    ``proxy``
        Accesses to the filesystem are done by virtfs-proxy-helper(1).

    ``synth``
        Synthetic filesystem, only used by QTests.

    ``id=id``
        Specifies identifier for this device.

    ``path=path``
        Specifies the export path for the file system device. Files
        under this path will be available to the 9p client on the guest.

    ``security_model=security_model``
        Specifies the security model to be used for this export path.
        Supported security models are "passthrough", "mapped-xattr",
        "mapped-file" and "none". In "passthrough" security model, files
        are stored using the same credentials as they are created on the
        guest. This requires QEMU to run as root. In "mapped-xattr"
        security model, some of the file attributes like uid, gid, mode
        bits and link target are stored as file attributes. For
        "mapped-file" these attributes are stored in the hidden
        .virtfs\_metadata directory. Directories exported by this
        security model cannot interact with other unix tools. "none"
        security model is same as passthrough except the sever won't
        report failures if it fails to set file attributes like
        ownership. Security model is mandatory only for local fsdriver.
        Other fsdrivers (like proxy) don't take security model as a
        parameter.

    ``writeout=writeout``
        This is an optional argument. The only supported value is
        "immediate". This means that host page cache will be used to
        read and write data but write notification will be sent to the
        guest only when the data has been reported as written by the
        storage subsystem.

    ``readonly=on``
        Enables exporting 9p share as a readonly mount for guests. By
        default read-write access is given.

    ``socket=socket``
        Enables proxy filesystem driver to use passed socket file for
        communicating with virtfs-proxy-helper(1).

    ``sock_fd=sock_fd``
        Enables proxy filesystem driver to use passed socket descriptor
        for communicating with virtfs-proxy-helper(1). Usually a helper
        like libvirt will create socketpair and pass one of the fds as
        sock\_fd.

    ``fmode=fmode``
        Specifies the default mode for newly created files on the host.
        Works only with security models "mapped-xattr" and
        "mapped-file".

    ``dmode=dmode``
        Specifies the default mode for newly created directories on the
        host. Works only with security models "mapped-xattr" and
        "mapped-file".

    ``throttling.bps-total=b,throttling.bps-read=r,throttling.bps-write=w``
        Specify bandwidth throttling limits in bytes per second, either
        for all request types or for reads or writes only.

    ``throttling.bps-total-max=bm,bps-read-max=rm,bps-write-max=wm``
        Specify bursts in bytes per second, either for all request types
        or for reads or writes only. Bursts allow the guest I/O to spike
        above the limit temporarily.

    ``throttling.iops-total=i,throttling.iops-read=r, throttling.iops-write=w``
        Specify request rate limits in requests per second, either for
        all request types or for reads or writes only.

    ``throttling.iops-total-max=im,throttling.iops-read-max=irm, throttling.iops-write-max=iwm``
        Specify bursts in requests per second, either for all request
        types or for reads or writes only. Bursts allow the guest I/O to
        spike above the limit temporarily.

    ``throttling.iops-size=is``
        Let every is bytes of a request count as a new request for iops
        throttling purposes.

    -fsdev option is used along with -device driver "virtio-9p-...".

``-device virtio-9p-type,fsdev=id,mount_tag=mount_tag``
    Options for virtio-9p-... driver are:

    ``type``
        Specifies the variant to be used. Supported values are "pci",
        "ccw" or "device", depending on the machine type.

    ``fsdev=id``
        Specifies the id value specified along with -fsdev option.

    ``mount_tag=mount_tag``
        Specifies the tag name to be used by the guest to mount this
        export point.
ERST

DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs,
    "-virtfs local,path=path,mount_tag=tag,security_model=mapped-xattr|mapped-file|passthrough|none\n"
    "        [,id=id][,writeout=immediate][,readonly=on][,fmode=fmode][,dmode=dmode][,multidevs=remap|forbid|warn]\n"
    "-virtfs proxy,mount_tag=tag,socket=socket[,id=id][,writeout=immediate][,readonly=on]\n"
    "-virtfs proxy,mount_tag=tag,sock_fd=sock_fd[,id=id][,writeout=immediate][,readonly=on]\n"
    "-virtfs synth,mount_tag=tag[,id=id][,readonly=on]\n",
    QEMU_ARCH_ALL)

SRST
``-virtfs local,path=path,mount_tag=mount_tag ,security_model=security_model[,writeout=writeout][,readonly=on] [,fmode=fmode][,dmode=dmode][,multidevs=multidevs]``
  \ 
``-virtfs proxy,socket=socket,mount_tag=mount_tag [,writeout=writeout][,readonly=on]``
  \ 
``-virtfs proxy,sock_fd=sock_fd,mount_tag=mount_tag [,writeout=writeout][,readonly=on]``
  \
``-virtfs synth,mount_tag=mount_tag``
    Define a new virtual filesystem device and expose it to the guest using
    a virtio-9p-device (a.k.a. 9pfs), which essentially means that a certain
    directory on host is made directly accessible by guest as a pass-through
    file system by using the 9P network protocol for communication between
    host and guests, if desired even accessible, shared by several guests
    simultaniously.

    Note that ``-virtfs`` is actually just a convenience shortcut for its
    generalized form ``-fsdev -device virtio-9p-pci``.

    The general form of pass-through file system options are:

    ``local``
        Accesses to the filesystem are done by QEMU.

    ``proxy``
        Accesses to the filesystem are done by virtfs-proxy-helper(1).

    ``synth``
        Synthetic filesystem, only used by QTests.

    ``id=id``
        Specifies identifier for the filesystem device

    ``path=path``
        Specifies the export path for the file system device. Files
        under this path will be available to the 9p client on the guest.

    ``security_model=security_model``
        Specifies the security model to be used for this export path.
        Supported security models are "passthrough", "mapped-xattr",
        "mapped-file" and "none". In "passthrough" security model, files
        are stored using the same credentials as they are created on the
        guest. This requires QEMU to run as root. In "mapped-xattr"
        security model, some of the file attributes like uid, gid, mode
        bits and link target are stored as file attributes. For
        "mapped-file" these attributes are stored in the hidden
        .virtfs\_metadata directory. Directories exported by this
        security model cannot interact with other unix tools. "none"
        security model is same as passthrough except the sever won't
        report failures if it fails to set file attributes like
        ownership. Security model is mandatory only for local fsdriver.
        Other fsdrivers (like proxy) don't take security model as a
        parameter.

    ``writeout=writeout``
        This is an optional argument. The only supported value is
        "immediate". This means that host page cache will be used to
        read and write data but write notification will be sent to the
        guest only when the data has been reported as written by the
        storage subsystem.

    ``readonly=on``
        Enables exporting 9p share as a readonly mount for guests. By
        default read-write access is given.

    ``socket=socket``
        Enables proxy filesystem driver to use passed socket file for
        communicating with virtfs-proxy-helper(1). Usually a helper like
        libvirt will create socketpair and pass one of the fds as
        sock\_fd.

    ``sock_fd``
        Enables proxy filesystem driver to use passed 'sock\_fd' as the
        socket descriptor for interfacing with virtfs-proxy-helper(1).

    ``fmode=fmode``
        Specifies the default mode for newly created files on the host.
        Works only with security models "mapped-xattr" and
        "mapped-file".

    ``dmode=dmode``
        Specifies the default mode for newly created directories on the
        host. Works only with security models "mapped-xattr" and
        "mapped-file".

    ``mount_tag=mount_tag``
        Specifies the tag name to be used by the guest to mount this
        export point.

    ``multidevs=multidevs``
        Specifies how to deal with multiple devices being shared with a
        9p export. Supported behaviours are either "remap", "forbid" or
        "warn". The latter is the default behaviour on which virtfs 9p
        expects only one device to be shared with the same export, and
        if more than one device is shared and accessed via the same 9p
        export then only a warning message is logged (once) by qemu on
        host side. In order to avoid file ID collisions on guest you
        should either create a separate virtfs export for each device to
        be shared with guests (recommended way) or you might use "remap"
        instead which allows you to share multiple devices with only one
        export instead, which is achieved by remapping the original
        inode numbers from host to guest in a way that would prevent
        such collisions. Remapping inodes in such use cases is required
        because the original device IDs from host are never passed and
        exposed on guest. Instead all files of an export shared with
        virtfs always share the same device id on guest. So two files
        with identical inode numbers but from actually different devices
        on host would otherwise cause a file ID collision and hence
        potential misbehaviours on guest. "forbid" on the other hand
        assumes like "warn" that only one device is shared by the same
        export, however it will not only log a warning message but also
        deny access to additional devices on guest. Note though that
        "forbid" does currently not block all possible file access
        operations (e.g. readdir() would still return entries from other
        devices).
ERST

DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi,
    "-iscsi [user=user][,password=password]\n"
    "       [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n"
    "       [,initiator-name=initiator-iqn][,id=target-iqn]\n"
    "       [,timeout=timeout]\n"
    "                iSCSI session parameters\n", QEMU_ARCH_ALL)

SRST
``-iscsi``
    Configure iSCSI session parameters.
ERST

DEFHEADING()

DEFHEADING(USB convenience options:)

DEF("usb", 0, QEMU_OPTION_usb,
    "-usb            enable on-board USB host controller (if not enabled by default)\n",
    QEMU_ARCH_ALL)
SRST
``-usb``
    Enable USB emulation on machine types with an on-board USB host
    controller (if not enabled by default). Note that on-board USB host
    controllers may not support USB 3.0. In this case
    ``-device qemu-xhci`` can be used instead on machines with PCI.
ERST

DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice,
    "-usbdevice name add the host or guest USB device 'name'\n",
    QEMU_ARCH_ALL)
SRST
``-usbdevice devname``
    Add the USB device devname, and enable an on-board USB controller
    if possible and necessary (just like it can be done via
    ``-machine usb=on``). Note that this option is mainly intended for
    the user's convenience only. More fine-grained control can be
    achieved by selecting a USB host controller (if necessary) and the
    desired USB device via the ``-device`` option instead. For example,
    instead of using ``-usbdevice mouse`` it is possible to use
    ``-device qemu-xhci -device usb-mouse`` to connect the USB mouse
    to a USB 3.0 controller instead (at least on machines that support
    PCI and do not have an USB controller enabled by default yet).
    For more details, see the chapter about
    :ref:`Connecting USB devices` in the System Emulation Users Guide.
    Possible devices for devname are:

    ``braille``
        Braille device. This will use BrlAPI to display the braille
        output on a real or fake device (i.e. it also creates a
        corresponding ``braille`` chardev automatically beside the
        ``usb-braille`` USB device).

    ``keyboard``
        Standard USB keyboard. Will override the PS/2 keyboard (if present).

    ``mouse``
        Virtual Mouse. This will override the PS/2 mouse emulation when
        activated.

    ``tablet``
        Pointer device that uses absolute coordinates (like a
        touchscreen). This means QEMU is able to report the mouse
        position without having to grab the mouse. Also overrides the
        PS/2 mouse emulation when activated.

    ``wacom-tablet``
        Wacom PenPartner USB tablet.


ERST

DEFHEADING()

DEFHEADING(Display options:)

DEF("display", HAS_ARG, QEMU_OPTION_display,
#if defined(CONFIG_SPICE)
    "-display spice-app[,gl=on|off]\n"
#endif
#if defined(CONFIG_SDL)
    "-display sdl[,alt_grab=on|off][,ctrl_grab=on|off][,gl=on|core|es|off]\n"
    "            [,grab-mod=<mod>][,show-cursor=on|off][,window-close=on|off]\n"
#endif
#if defined(CONFIG_GTK)
    "-display gtk[,full-screen=on|off][,gl=on|off][,grab-on-hover=on|off]\n"
    "            [,show-cursor=on|off][,window-close=on|off]\n"
#endif
#if defined(CONFIG_VNC)
    "-display vnc=<display>[,<optargs>]\n"
#endif
#if defined(CONFIG_CURSES)
    "-display curses[,charset=<encoding>]\n"
#endif
#if defined(CONFIG_OPENGL)
    "-display egl-headless[,rendernode=<file>]\n"
#endif
    "-display none\n"
    "                select display backend type\n"
    "                The default display is equivalent to\n                "
#if defined(CONFIG_GTK)
            "\"-display gtk\"\n"
#elif defined(CONFIG_SDL)
            "\"-display sdl\"\n"
#elif defined(CONFIG_COCOA)
            "\"-display cocoa\"\n"
#elif defined(CONFIG_VNC)
            "\"-vnc localhost:0,to=99,id=default\"\n"
#else
            "\"-display none\"\n"
#endif
    , QEMU_ARCH_ALL)
SRST
``-display type``
    Select type of display to use. This option is a replacement for the
    old style -sdl/-curses/... options. Use ``-display help`` to list
    the available display types. Valid values for type are

    ``spice-app[,gl=on|off]``
        Start QEMU as a Spice server and launch the default Spice client
        application. The Spice server will redirect the serial consoles
        and QEMU monitors. (Since 4.0)

    ``sdl``
        Display video output via SDL (usually in a separate graphics
        window; see the SDL documentation for other possibilities).
        Valid parameters are:

        ``grab-mod=<mods>`` : Used to select the modifier keys for toggling
        the mouse grabbing in conjunction with the "g" key. ``<mods>`` can be
        either ``lshift-lctrl-lalt`` or ``rctrl``.

        ``alt_grab=on|off`` : Use Control+Alt+Shift-g to toggle mouse grabbing.
        This parameter is deprecated - use ``grab-mod`` instead.

        ``ctrl_grab=on|off`` : Use Right-Control-g to toggle mouse grabbing.
        This parameter is deprecated - use ``grab-mod`` instead.

        ``gl=on|off|core|es`` : Use OpenGL for displaying

        ``show-cursor=on|off`` :  Force showing the mouse cursor

        ``window-close=on|off`` : Allow to quit qemu with window close button

    ``gtk``
        Display video output in a GTK window. This interface provides
        drop-down menus and other UI elements to configure and control
        the VM during runtime. Valid parameters are:

        ``full-screen=on|off`` : Start in fullscreen mode

        ``gl=on|off`` : Use OpenGL for displaying

        ``grab-on-hover=on|off`` : Grab keyboard input on mouse hover

        ``show-cursor=on|off`` :  Force showing the mouse cursor

        ``window-close=on|off`` : Allow to quit qemu with window close button

    ``curses[,charset=<encoding>]``
        Display video output via curses. For graphics device models
        which support a text mode, QEMU can display this output using a
        curses/ncurses interface. Nothing is displayed when the graphics
        device is in graphical mode or if the graphics device does not
        support a text mode. Generally only the VGA device models
        support text mode. The font charset used by the guest can be
        specified with the ``charset`` option, for example
        ``charset=CP850`` for IBM CP850 encoding. The default is
        ``CP437``.

    ``egl-headless[,rendernode=<file>]``
        Offload all OpenGL operations to a local DRI device. For any
        graphical display, this display needs to be paired with either
        VNC or SPICE displays.

    ``vnc=<display>``
        Start a VNC server on display <display>

    ``none``
        Do not display video output. The guest will still see an
        emulated graphics card, but its output will not be displayed to
        the QEMU user. This option differs from the -nographic option in
        that it only affects what is done with video output; -nographic
        also changes the destination of the serial and parallel port
        data.
ERST

DEF("nographic", 0, QEMU_OPTION_nographic,
    "-nographic      disable graphical output and redirect serial I/Os to console\n",
    QEMU_ARCH_ALL)
SRST
``-nographic``
    Normally, if QEMU is compiled with graphical window support, it
    displays output such as guest graphics, guest console, and the QEMU
    monitor in a window. With this option, you can totally disable
    graphical output so that QEMU is a simple command line application.
    The emulated serial port is redirected on the console and muxed with
    the monitor (unless redirected elsewhere explicitly). Therefore, you
    can still use QEMU to debug a Linux kernel with a serial console.
    Use C-a h for help on switching between the console and monitor.
ERST

DEF("curses", 0, QEMU_OPTION_curses,
    "-curses         shorthand for -display curses\n",
    QEMU_ARCH_ALL)
SRST
``-curses``
    Normally, if QEMU is compiled with graphical window support, it
    displays output such as guest graphics, guest console, and the QEMU
    monitor in a window. With this option, QEMU can display the VGA
    output when in text mode using a curses/ncurses interface. Nothing
    is displayed in graphical mode.
ERST

DEF("alt-grab", 0, QEMU_OPTION_alt_grab,
    "-alt-grab       use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n",
    QEMU_ARCH_ALL)
SRST
``-alt-grab``
    Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that
    this also affects the special keys (for fullscreen, monitor-mode
    switching, etc). This option is deprecated - please use
    ``-display sdl,grab-mod=lshift-lctrl-lalt`` instead.
ERST

DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab,
    "-ctrl-grab      use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n",
    QEMU_ARCH_ALL)
SRST
``-ctrl-grab``
    Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this
    also affects the special keys (for fullscreen, monitor-mode
    switching, etc). This option is deprecated - please use
    ``-display sdl,grab-mod=rctrl`` instead.
ERST

DEF("no-quit", 0, QEMU_OPTION_no_quit,
    "-no-quit        disable SDL/GTK window close capability (deprecated)\n", QEMU_ARCH_ALL)
SRST
``-no-quit``
    Disable window close capability (SDL and GTK only). This option is
    deprecated, please use ``-display ...,window-close=off`` instead.
ERST

DEF("sdl", 0, QEMU_OPTION_sdl,
    "-sdl            shorthand for -display sdl\n", QEMU_ARCH_ALL)
SRST
``-sdl``
    Enable SDL.
ERST

DEF("spice", HAS_ARG, QEMU_OPTION_spice,
    "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n"
    "       [,x509-key-file=<file>][,x509-key-password=<file>]\n"
    "       [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n"
    "       [,x509-dh-key-file=<file>][,addr=addr]\n"
    "       [,ipv4=on|off][,ipv6=on|off][,unix=on|off]\n"
    "       [,tls-ciphers=<list>]\n"
    "       [,tls-channel=[main|display|cursor|inputs|record|playback]]\n"
    "       [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n"
    "       [,sasl=on|off][,disable-ticketing=on|off]\n"
    "       [,password=<string>][,password-secret=<secret-id>]\n"
    "       [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n"
    "       [,jpeg-wan-compression=[auto|never|always]]\n"
    "       [,zlib-glz-wan-compression=[auto|never|always]]\n"
    "       [,streaming-video=[off|all|filter]][,disable-copy-paste=on|off]\n"
    "       [,disable-agent-file-xfer=on|off][,agent-mouse=[on|off]]\n"
    "       [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n"
    "       [,gl=[on|off]][,rendernode=<file>]\n"
    "   enable spice\n"
    "   at least one of {port, tls-port} is mandatory\n",
    QEMU_ARCH_ALL)
SRST
``-spice option[,option[,...]]``
    Enable the spice remote desktop protocol. Valid options are

    ``port=<nr>``
        Set the TCP port spice is listening on for plaintext channels.

    ``addr=<addr>``
        Set the IP address spice is listening on. Default is any
        address.

    ``ipv4=on|off``; \ ``ipv6=on|off``; \ ``unix=on|off``
        Force using the specified IP version.

    ``password=<string>``
        Set the password you need to authenticate.

        This option is deprecated and insecure because it leaves the
        password visible in the process listing. Use ``password-secret``
        instead.

    ``password-secret=<secret-id>``
        Set the ID of the ``secret`` object containing the password
        you need to authenticate.

    ``sasl=on|off``
        Require that the client use SASL to authenticate with the spice.
        The exact choice of authentication method used is controlled
        from the system / user's SASL configuration file for the 'qemu'
        service. This is typically found in /etc/sasl2/qemu.conf. If
        running QEMU as an unprivileged user, an environment variable
        SASL\_CONF\_PATH can be used to make it search alternate
        locations for the service config. While some SASL auth methods
        can also provide data encryption (eg GSSAPI), it is recommended
        that SASL always be combined with the 'tls' and 'x509' settings
        to enable use of SSL and server certificates. This ensures a
        data encryption preventing compromise of authentication
        credentials.

    ``disable-ticketing=on|off``
        Allow client connects without authentication.

    ``disable-copy-paste=on|off``
        Disable copy paste between the client and the guest.

    ``disable-agent-file-xfer=on|off``
        Disable spice-vdagent based file-xfer between the client and the
        guest.

    ``tls-port=<nr>``
        Set the TCP port spice is listening on for encrypted channels.

    ``x509-dir=<dir>``
        Set the x509 file directory. Expects same filenames as -vnc
        $display,x509=$dir

    ``x509-key-file=<file>``; \ ``x509-key-password=<file>``; \ ``x509-cert-file=<file>``; \ ``x509-cacert-file=<file>``; \ ``x509-dh-key-file=<file>``
        The x509 file names can also be configured individually.

    ``tls-ciphers=<list>``
        Specify which ciphers to use.

    ``tls-channel=[main|display|cursor|inputs|record|playback]``; \ ``plaintext-channel=[main|display|cursor|inputs|record|playback]``
        Force specific channel to be used with or without TLS
        encryption. The options can be specified multiple times to
        configure multiple channels. The special name "default" can be
        used to set the default mode. For channels which are not
        explicitly forced into one mode the spice client is allowed to
        pick tls/plaintext as he pleases.

    ``image-compression=[auto_glz|auto_lz|quic|glz|lz|off]``
        Configure image compression (lossless). Default is auto\_glz.

    ``jpeg-wan-compression=[auto|never|always]``; \ ``zlib-glz-wan-compression=[auto|never|always]``
        Configure wan image compression (lossy for slow links). Default
        is auto.

    ``streaming-video=[off|all|filter]``
        Configure video stream detection. Default is off.

    ``agent-mouse=[on|off]``
        Enable/disable passing mouse events via vdagent. Default is on.

    ``playback-compression=[on|off]``
        Enable/disable audio stream compression (using celt 0.5.1).
        Default is on.

    ``seamless-migration=[on|off]``
        Enable/disable spice seamless migration. Default is off.

    ``gl=[on|off]``
        Enable/disable OpenGL context. Default is off.

    ``rendernode=<file>``
        DRM render node for OpenGL rendering. If not specified, it will
        pick the first available. (Since 2.9)
ERST

DEF("portrait", 0, QEMU_OPTION_portrait,
    "-portrait       rotate graphical output 90 deg left (only PXA LCD)\n",
    QEMU_ARCH_ALL)
SRST
``-portrait``
    Rotate graphical output 90 deg left (only PXA LCD).
ERST

DEF("rotate", HAS_ARG, QEMU_OPTION_rotate,
    "-rotate <deg>   rotate graphical output some deg left (only PXA LCD)\n",
    QEMU_ARCH_ALL)
SRST
``-rotate deg``
    Rotate graphical output some deg left (only PXA LCD).
ERST

DEF("vga", HAS_ARG, QEMU_OPTION_vga,
    "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|virtio|none]\n"
    "                select video card type\n", QEMU_ARCH_ALL)
SRST
``-vga type``
    Select type of VGA card to emulate. Valid values for type are

    ``cirrus``
        Cirrus Logic GD5446 Video card. All Windows versions starting
        from Windows 95 should recognize and use this graphic card. For
        optimal performances, use 16 bit color depth in the guest and
        the host OS. (This card was the default before QEMU 2.2)

    ``std``
        Standard VGA card with Bochs VBE extensions. If your guest OS
        supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if
        you want to use high resolution modes (>= 1280x1024x16) then you
        should use this option. (This card is the default since QEMU
        2.2)

    ``vmware``
        VMWare SVGA-II compatible adapter. Use it if you have
        sufficiently recent XFree86/XOrg server or Windows guest with a
        driver for this card.

    ``qxl``
        QXL paravirtual graphic card. It is VGA compatible (including
        VESA 2.0 VBE support). Works best with qxl guest drivers
        installed though. Recommended choice when using the spice
        protocol.

    ``tcx``
        (sun4m only) Sun TCX framebuffer. This is the default
        framebuffer for sun4m machines and offers both 8-bit and 24-bit
        colour depths at a fixed resolution of 1024x768.

    ``cg3``
        (sun4m only) Sun cgthree framebuffer. This is a simple 8-bit
        framebuffer for sun4m machines available in both 1024x768
        (OpenBIOS) and 1152x900 (OBP) resolutions aimed at people
        wishing to run older Solaris versions.

    ``virtio``
        Virtio VGA card.

    ``none``
        Disable VGA card.
ERST

DEF("full-screen", 0, QEMU_OPTION_full_screen,
    "-full-screen    start in full screen\n", QEMU_ARCH_ALL)
SRST
``-full-screen``
    Start in full screen.
ERST

DEF("g", HAS_ARG, QEMU_OPTION_g ,
    "-g WxH[xDEPTH]  Set the initial graphical resolution and depth\n",
    QEMU_ARCH_PPC | QEMU_ARCH_SPARC | QEMU_ARCH_M68K)
SRST
``-g`` *width*\ ``x``\ *height*\ ``[x``\ *depth*\ ``]``
    Set the initial graphical resolution and depth (PPC, SPARC only).

    For PPC the default is 800x600x32.

    For SPARC with the TCX graphics device, the default is 1024x768x8
    with the option of 1024x768x24. For cgthree, the default is
    1024x768x8 with the option of 1152x900x8 for people who wish to use
    OBP.
ERST

DEF("vnc", HAS_ARG, QEMU_OPTION_vnc ,
    "-vnc <display>  shorthand for -display vnc=<display>\n", QEMU_ARCH_ALL)
SRST
``-vnc display[,option[,option[,...]]]``
    Normally, if QEMU is compiled with graphical window support, it
    displays output such as guest graphics, guest console, and the QEMU
    monitor in a window. With this option, you can have QEMU listen on
    VNC display display and redirect the VGA display over the VNC
    session. It is very useful to enable the usb tablet device when
    using this option (option ``-device usb-tablet``). When using the
    VNC display, you must use the ``-k`` parameter to set the keyboard
    layout if you are not using en-us. Valid syntax for the display is

    ``to=L``
        With this option, QEMU will try next available VNC displays,
        until the number L, if the origianlly defined "-vnc display" is
        not available, e.g. port 5900+display is already used by another
        application. By default, to=0.

    ``host:d``
        TCP connections will only be allowed from host on display d. By
        convention the TCP port is 5900+d. Optionally, host can be
        omitted in which case the server will accept connections from
        any host.

    ``unix:path``
        Connections will be allowed over UNIX domain sockets where path
        is the location of a unix socket to listen for connections on.

    ``none``
        VNC is initialized but not started. The monitor ``change``
        command can be used to later start the VNC server.

    Following the display value there may be one or more option flags
    separated by commas. Valid options are

    ``reverse=on|off``
        Connect to a listening VNC client via a "reverse" connection.
        The client is specified by the display. For reverse network
        connections (host:d,``reverse``), the d argument is a TCP port
        number, not a display number.

    ``websocket=on|off``
        Opens an additional TCP listening port dedicated to VNC
        Websocket connections. If a bare websocket option is given, the
        Websocket port is 5700+display. An alternative port can be
        specified with the syntax ``websocket``\ =port.

        If host is specified connections will only be allowed from this
        host. It is possible to control the websocket listen address
        independently, using the syntax ``websocket``\ =host:port.

        If no TLS credentials are provided, the websocket connection
        runs in unencrypted mode. If TLS credentials are provided, the
        websocket connection requires encrypted client connections.

    ``password=on|off``
        Require that password based authentication is used for client
        connections.

        The password must be set separately using the ``set_password``
        command in the :ref:`QEMU monitor`. The
        syntax to change your password is:
        ``set_password <protocol> <password>`` where <protocol> could be
        either "vnc" or "spice".

        If you would like to change <protocol> password expiration, you
        should use ``expire_password <protocol> <expiration-time>``
        where expiration time could be one of the following options:
        now, never, +seconds or UNIX time of expiration, e.g. +60 to
        make password expire in 60 seconds, or 1335196800 to make
        password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for
        this date and time).

        You can also use keywords "now" or "never" for the expiration
        time to allow <protocol> password to expire immediately or never
        expire.

    ``password-secret=<secret-id>``
        Require that password based authentication is used for client
        connections, using the password provided by the ``secret``
        object identified by ``secret-id``.

    ``tls-creds=ID``
        Provides the ID of a set of TLS credentials to use to secure the
        VNC server. They will apply to both the normal VNC server socket
        and the websocket socket (if enabled). Setting TLS credentials
        will cause the VNC server socket to enable the VeNCrypt auth
        mechanism. The credentials should have been previously created
        using the ``-object tls-creds`` argument.

    ``tls-authz=ID``
        Provides the ID of the QAuthZ authorization object against which
        the client's x509 distinguished name will validated. This object
        is only resolved at time of use, so can be deleted and recreated
        on the fly while the VNC server is active. If missing, it will
        default to denying access.

    ``sasl=on|off``
        Require that the client use SASL to authenticate with the VNC
        server. The exact choice of authentication method used is
        controlled from the system / user's SASL configuration file for
        the 'qemu' service. This is typically found in
        /etc/sasl2/qemu.conf. If running QEMU as an unprivileged user,
        an environment variable SASL\_CONF\_PATH can be used to make it
        search alternate locations for the service config. While some
        SASL auth methods can also provide data encryption (eg GSSAPI),
        it is recommended that SASL always be combined with the 'tls'
        and 'x509' settings to enable use of SSL and server
        certificates. This ensures a data encryption preventing
        compromise of authentication credentials. See the
        :ref:`VNC security` section in the System Emulation Users Guide
        for details on using SASL authentication.

    ``sasl-authz=ID``
        Provides the ID of the QAuthZ authorization object against which
        the client's SASL username will validated. This object is only
        resolved at time of use, so can be deleted and recreated on the
        fly while the VNC server is active. If missing, it will default
        to denying access.

    ``acl=on|off``
        Legacy method for enabling authorization of clients against the
        x509 distinguished name and SASL username. It results in the
        creation of two ``authz-list`` objects with IDs of
        ``vnc.username`` and ``vnc.x509dname``. The rules for these
        objects must be configured with the HMP ACL commands.

        This option is deprecated and should no longer be used. The new
        ``sasl-authz`` and ``tls-authz`` options are a replacement.

    ``lossy=on|off``
        Enable lossy compression methods (gradient, JPEG, ...). If this
        option is set, VNC client may receive lossy framebuffer updates
        depending on its encoding settings. Enabling this option can
        save a lot of bandwidth at the expense of quality.

    ``non-adaptive=on|off``
        Disable adaptive encodings. Adaptive encodings are enabled by
        default. An adaptive encoding will try to detect frequently
        updated screen regions, and send updates in these regions using
        a lossy encoding (like JPEG). This can be really helpful to save
        bandwidth when playing videos. Disabling adaptive encodings
        restores the original static behavior of encodings like Tight.

    ``share=[allow-exclusive|force-shared|ignore]``
        Set display sharing policy. 'allow-exclusive' allows clients to
        ask for exclusive access. As suggested by the rfb spec this is
        implemented by dropping other connections. Connecting multiple
        clients in parallel requires all clients asking for a shared
        session (vncviewer: -shared switch). This is the default.
        'force-shared' disables exclusive client access. Useful for
        shared desktop sessions, where you don't want someone forgetting
        specify -shared disconnect everybody else. 'ignore' completely
        ignores the shared flag and allows everybody connect
        unconditionally. Doesn't conform to the rfb spec but is
        traditional QEMU behavior.

    ``key-delay-ms``
        Set keyboard delay, for key down and key up events, in
        milliseconds. Default is 10. Keyboards are low-bandwidth
        devices, so this slowdown can help the device and guest to keep
        up and not lose events in case events are arriving in bulk.
        Possible causes for the latter are flaky network connections, or
        scripts for automated testing.

    ``audiodev=audiodev``
        Use the specified audiodev when the VNC client requests audio
        transmission. When not using an -audiodev argument, this option
        must be omitted, otherwise is must be present and specify a
        valid audiodev.

    ``power-control=on|off``
        Permit the remote client to issue shutdown, reboot or reset power
        control requests.
ERST

ARCHHEADING(, QEMU_ARCH_I386)

ARCHHEADING(i386 target only:, QEMU_ARCH_I386)

DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack,
    "-win2k-hack     use it when installing Windows 2000 to avoid a disk full bug\n",
    QEMU_ARCH_I386)
SRST
``-win2k-hack``
    Use it when installing Windows 2000 to avoid a disk full bug. After
    Windows 2000 is installed, you no longer need this option (this
    option slows down the IDE transfers).
ERST

DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk,
    "-no-fd-bootchk  disable boot signature checking for floppy disks\n",
    QEMU_ARCH_I386)
SRST
``-no-fd-bootchk``
    Disable boot signature checking for floppy disks in BIOS. May be
    needed to boot from old floppy disks.
ERST

DEF("no-acpi", 0, QEMU_OPTION_no_acpi,
           "-no-acpi        disable ACPI\n", QEMU_ARCH_I386 | QEMU_ARCH_ARM)
SRST
``-no-acpi``
    Disable ACPI (Advanced Configuration and Power Interface) support.
    Use it if your guest OS complains about ACPI problems (PC target
    machine only).
ERST

DEF("no-hpet", 0, QEMU_OPTION_no_hpet,
    "-no-hpet        disable HPET\n", QEMU_ARCH_I386)
SRST
``-no-hpet``
    Disable HPET support.
ERST

DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable,
    "-acpitable [sig=str][,rev=n][,oem_id=str][,oem_table_id=str][,oem_rev=n][,asl_compiler_id=str][,asl_compiler_rev=n][,{data|file}=file1[:file2]...]\n"
    "                ACPI table description\n", QEMU_ARCH_I386)
SRST
``-acpitable [sig=str][,rev=n][,oem_id=str][,oem_table_id=str][,oem_rev=n] [,asl_compiler_id=str][,asl_compiler_rev=n][,data=file1[:file2]...]``
    Add ACPI table with specified header fields and context from
    specified files. For file=, take whole ACPI table from the specified
    files, including all ACPI headers (possible overridden by other
    options). For data=, only data portion of the table is used, all
    header information is specified in the command line. If a SLIC table
    is supplied to QEMU, then the SLIC's oem\_id and oem\_table\_id
    fields will override the same in the RSDT and the FADT (a.k.a.
    FACP), in order to ensure the field matches required by the
    Microsoft SLIC spec and the ACPI spec.
ERST

DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
    "-smbios file=binary\n"
    "                load SMBIOS entry from binary file\n"
    "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n"
    "              [,uefi=on|off]\n"
    "                specify SMBIOS type 0 fields\n"
    "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
    "              [,uuid=uuid][,sku=str][,family=str]\n"
    "                specify SMBIOS type 1 fields\n"
    "-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
    "              [,asset=str][,location=str]\n"
    "                specify SMBIOS type 2 fields\n"
    "-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str]\n"
    "              [,sku=str]\n"
    "                specify SMBIOS type 3 fields\n"
    "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n"
    "              [,asset=str][,part=str][,max-speed=%d][,current-speed=%d]\n"
    "                specify SMBIOS type 4 fields\n"
    "-smbios type=11[,value=str][,path=filename]\n"
    "                specify SMBIOS type 11 fields\n"
    "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n"
    "               [,asset=str][,part=str][,speed=%d]\n"
    "                specify SMBIOS type 17 fields\n"
    "-smbios type=41[,designation=str][,kind=str][,instance=%d][,pcidev=str]\n"
    "                specify SMBIOS type 41 fields\n",
    QEMU_ARCH_I386 | QEMU_ARCH_ARM)
SRST
``-smbios file=binary``
    Load SMBIOS entry from binary file.

``-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d][,uefi=on|off]``
    Specify SMBIOS type 0 fields

``-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str][,uuid=uuid][,sku=str][,family=str]``
    Specify SMBIOS type 1 fields

``-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str][,asset=str][,location=str]``
    Specify SMBIOS type 2 fields

``-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str][,sku=str]``
    Specify SMBIOS type 3 fields

``-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str][,asset=str][,part=str]``
    Specify SMBIOS type 4 fields

``-smbios type=11[,value=str][,path=filename]``
    Specify SMBIOS type 11 fields

    This argument can be repeated multiple times, and values are added in the order they are parsed.
    Applications intending to use OEM strings data are encouraged to use their application name as
    a prefix for the value string. This facilitates passing information for multiple applications
    concurrently.

    The ``value=str`` syntax provides the string data inline, while the ``path=filename`` syntax
    loads data from a file on disk. Note that the file is not permitted to contain any NUL bytes.

    Both the ``value`` and ``path`` options can be repeated multiple times and will be added to
    the SMBIOS table in the order in which they appear.

    Note that on the x86 architecture, the total size of all SMBIOS tables is limited to 65535
    bytes. Thus the OEM strings data is not suitable for passing large amounts of data into the
    guest. Instead it should be used as a indicator to inform the guest where to locate the real
    data set, for example, by specifying the serial ID of a block device.

    An example passing three strings is

    .. parsed-literal::

        -smbios type=11,value=cloud-init:ds=nocloud-net;s=http://10.10.0.1:8000/,\\
                        value=anaconda:method=http://dl.fedoraproject.org/pub/fedora/linux/releases/25/x86_64/os,\\
                        path=/some/file/with/oemstringsdata.txt

    In the guest OS this is visible with the ``dmidecode`` command

     .. parsed-literal::

         $ dmidecode -t 11
         Handle 0x0E00, DMI type 11, 5 bytes
         OEM Strings
              String 1: cloud-init:ds=nocloud-net;s=http://10.10.0.1:8000/
              String 2: anaconda:method=http://dl.fedoraproject.org/pub/fedora/linux/releases/25/x86_64/os
              String 3: myapp:some extra data


``-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str][,asset=str][,part=str][,speed=%d]``
    Specify SMBIOS type 17 fields

``-smbios type=41[,designation=str][,kind=str][,instance=%d][,pcidev=str]``
    Specify SMBIOS type 41 fields

    This argument can be repeated multiple times.  Its main use is to allow network interfaces be created
    as ``enoX`` on Linux, with X being the instance number, instead of the name depending on the interface
    position on the PCI bus.

    Here is an example of use:

    .. parsed-literal::

        -netdev user,id=internet \\
        -device virtio-net-pci,mac=50:54:00:00:00:42,netdev=internet,id=internet-dev \\
        -smbios type=41,designation='Onboard LAN',instance=1,kind=ethernet,pcidev=internet-dev

    In the guest OS, the device should then appear as ``eno1``:

    ..parsed-literal::

         $ ip -brief l
         lo               UNKNOWN        00:00:00:00:00:00 <LOOPBACK,UP,LOWER_UP>
         eno1             UP             50:54:00:00:00:42 <BROADCAST,MULTICAST,UP,LOWER_UP>

    Currently, the PCI device has to be attached to the root bus.

ERST

DEFHEADING()

DEFHEADING(Network options:)

DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
#ifdef CONFIG_SLIRP
    "-netdev user,id=str[,ipv4=on|off][,net=addr[/mask]][,host=addr]\n"
    "         [,ipv6=on|off][,ipv6-net=addr[/int]][,ipv6-host=addr]\n"
    "         [,restrict=on|off][,hostname=host][,dhcpstart=addr]\n"
    "         [,dns=addr][,ipv6-dns=addr][,dnssearch=domain][,domainname=domain]\n"
    "         [,tftp=dir][,tftp-server-name=name][,bootfile=f][,hostfwd=rule][,guestfwd=rule]"
#ifndef _WIN32
                                             "[,smb=dir[,smbserver=addr]]\n"
#endif
    "                configure a user mode network backend with ID 'str',\n"
    "                its DHCP server and optional services\n"
#endif
#ifdef _WIN32
    "-netdev tap,id=str,ifname=name\n"
    "                configure a host TAP network backend with ID 'str'\n"
#else
    "-netdev tap,id=str[,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile]\n"
    "         [,br=bridge][,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off]\n"
    "         [,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n"
    "         [,poll-us=n]\n"
    "                configure a host TAP network backend with ID 'str'\n"
    "                connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
    "                use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n"
    "                to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n"
    "                to deconfigure it\n"
    "                use '[down]script=no' to disable script execution\n"
    "                use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n"
    "                configure it\n"
    "                use 'fd=h' to connect to an already opened TAP interface\n"
    "                use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n"
    "                use 'sndbuf=nbytes' to limit the size of the send buffer (the\n"
    "                default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n"
    "                use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n"
    "                use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
    "                use vhost=on to enable experimental in kernel accelerator\n"
    "                    (only has effect for virtio guests which use MSIX)\n"
    "                use vhostforce=on to force vhost on for non-MSIX virtio guests\n"
    "                use 'vhostfd=h' to connect to an already opened vhost net device\n"
    "                use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n"
    "                use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n"
    "                use 'poll-us=n' to specify the maximum number of microseconds that could be\n"
    "                spent on busy polling for vhost net\n"
    "-netdev bridge,id=str[,br=bridge][,helper=helper]\n"
    "                configure a host TAP network backend with ID 'str' that is\n"
    "                connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
    "                using the program 'helper (default=" DEFAULT_BRIDGE_HELPER ")\n"
#endif
#ifdef __linux__
    "-netdev l2tpv3,id=str,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport]\n"
    "         [,rxsession=rxsession],txsession=txsession[,ipv6=on|off][,udp=on|off]\n"
    "         [,cookie64=on|off][,counter][,pincounter][,txcookie=txcookie]\n"
    "         [,rxcookie=rxcookie][,offset=offset]\n"
    "                configure a network backend with ID 'str' connected to\n"
    "                an Ethernet over L2TPv3 pseudowire.\n"
    "                Linux kernel 3.3+ as well as most routers can talk\n"
    "                L2TPv3. This transport allows connecting a VM to a VM,\n"
    "                VM to a router and even VM to Host. It is a nearly-universal\n"
    "                standard (RFC3931). Note - this implementation uses static\n"
    "                pre-configured tunnels (same as the Linux kernel).\n"
    "                use 'src=' to specify source address\n"
    "                use 'dst=' to specify destination address\n"
    "                use 'udp=on' to specify udp encapsulation\n"
    "                use 'srcport=' to specify source udp port\n"
    "                use 'dstport=' to specify destination udp port\n"
    "                use 'ipv6=on' to force v6\n"
    "                L2TPv3 uses cookies to prevent misconfiguration as\n"
    "                well as a weak security measure\n"
    "                use 'rxcookie=0x012345678' to specify a rxcookie\n"
    "                use 'txcookie=0x012345678' to specify a txcookie\n"
    "                use 'cookie64=on' to set cookie size to 64 bit, otherwise 32\n"
    "                use 'counter=off' to force a 'cut-down' L2TPv3 with no counter\n"
    "                use 'pincounter=on' to work around broken counter handling in peer\n"
    "                use 'offset=X' to add an extra offset between header and data\n"
#endif
    "-netdev socket,id=str[,fd=h][,listen=[host]:port][,connect=host:port]\n"
    "                configure a network backend to connect to another network\n"
    "                using a socket connection\n"
    "-netdev socket,id=str[,fd=h][,mcast=maddr:port[,localaddr=addr]]\n"
    "                configure a network backend to connect to a multicast maddr and port\n"
    "                use 'localaddr=addr' to specify the host address to send packets from\n"
    "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n"
    "                configure a network backend to connect to another network\n"
    "                using an UDP tunnel\n"
#ifdef CONFIG_VDE
    "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
    "                configure a network backend to connect to port 'n' of a vde switch\n"
    "                running on host and listening for incoming connections on 'socketpath'.\n"
    "                Use group 'groupname' and mode 'octalmode' to change default\n"
    "                ownership and permissions for communication port.\n"
#endif
#ifdef CONFIG_NETMAP
    "-netdev netmap,id=str,ifname=name[,devname=nmname]\n"
    "                attach to the existing netmap-enabled network interface 'name', or to a\n"
    "                VALE port (created on the fly) called 'name' ('nmname' is name of the \n"
    "                netmap device, defaults to '/dev/netmap')\n"
#endif
#ifdef CONFIG_POSIX
    "-netdev vhost-user,id=str,chardev=dev[,vhostforce=on|off]\n"
    "                configure a vhost-user network, backed by a chardev 'dev'\n"
#endif
#ifdef __linux__
    "-netdev vhost-vdpa,id=str,vhostdev=/path/to/dev\n"
    "                configure a vhost-vdpa network,Establish a vhost-vdpa netdev\n"
#endif
    "-netdev hubport,id=str,hubid=n[,netdev=nd]\n"
    "                configure a hub port on the hub with ID 'n'\n", QEMU_ARCH_ALL)
DEF("nic", HAS_ARG, QEMU_OPTION_nic,
    "-nic [tap|bridge|"
#ifdef CONFIG_SLIRP
    "user|"
#endif
#ifdef __linux__
    "l2tpv3|"
#endif
#ifdef CONFIG_VDE
    "vde|"
#endif
#ifdef CONFIG_NETMAP
    "netmap|"
#endif
#ifdef CONFIG_POSIX
    "vhost-user|"
#endif
    "socket][,option][,...][mac=macaddr]\n"
    "                initialize an on-board / default host NIC (using MAC address\n"
    "                macaddr) and connect it to the given host network backend\n"
    "-nic none       use it alone to have zero network devices (the default is to\n"
    "                provided a 'user' network connection)\n",
    QEMU_ARCH_ALL)
DEF("net", HAS_ARG, QEMU_OPTION_net,
    "-net nic[,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
    "                configure or create an on-board (or machine default) NIC and\n"
    "                connect it to hub 0 (please use -nic unless you need a hub)\n"
    "-net ["
#ifdef CONFIG_SLIRP
    "user|"
#endif
    "tap|"
    "bridge|"
#ifdef CONFIG_VDE
    "vde|"
#endif
#ifdef CONFIG_NETMAP
    "netmap|"
#endif
    "socket][,option][,option][,...]\n"
    "                old way to initialize a host network interface\n"
    "                (use the -netdev option if possible instead)\n", QEMU_ARCH_ALL)
SRST
``-nic [tap|bridge|user|l2tpv3|vde|netmap|vhost-user|socket][,...][,mac=macaddr][,model=mn]``
    This option is a shortcut for configuring both the on-board
    (default) guest NIC hardware and the host network backend in one go.
    The host backend options are the same as with the corresponding
    ``-netdev`` options below. The guest NIC model can be set with
    ``model=modelname``. Use ``model=help`` to list the available device
    types. The hardware MAC address can be set with ``mac=macaddr``.

    The following two example do exactly the same, to show how ``-nic``
    can be used to shorten the command line length:

    .. parsed-literal::

        |qemu_system| -netdev user,id=n1,ipv6=off -device e1000,netdev=n1,mac=52:54:98:76:54:32
        |qemu_system| -nic user,ipv6=off,model=e1000,mac=52:54:98:76:54:32

``-nic none``
    Indicate that no network devices should be configured. It is used to
    override the default configuration (default NIC with "user" host
    network backend) which is activated if no other networking options
    are provided.

``-netdev user,id=id[,option][,option][,...]``
    Configure user mode host network backend which requires no
    administrator privilege to run. Valid options are:

    ``id=id``
        Assign symbolic name for use in monitor commands.

    ``ipv4=on|off and ipv6=on|off``
        Specify that either IPv4 or IPv6 must be enabled. If neither is
        specified both protocols are enabled.

    ``net=addr[/mask]``
        Set IP network address the guest will see. Optionally specify
        the netmask, either in the form a.b.c.d or as number of valid
        top-most bits. Default is 10.0.2.0/24.

    ``host=addr``
        Specify the guest-visible address of the host. Default is the
        2nd IP in the guest network, i.e. x.x.x.2.

    ``ipv6-net=addr[/int]``
        Set IPv6 network address the guest will see (default is
        fec0::/64). The network prefix is given in the usual hexadecimal
        IPv6 address notation. The prefix size is optional, and is given
        as the number of valid top-most bits (default is 64).

    ``ipv6-host=addr``
        Specify the guest-visible IPv6 address of the host. Default is
        the 2nd IPv6 in the guest network, i.e. xxxx::2.

    ``restrict=on|off``
        If this option is enabled, the guest will be isolated, i.e. it
        will not be able to contact the host and no guest IP packets
        will be routed over the host to the outside. This option does
        not affect any explicitly set forwarding rules.

    ``hostname=name``
        Specifies the client hostname reported by the built-in DHCP
        server.

    ``dhcpstart=addr``
        Specify the first of the 16 IPs the built-in DHCP server can
        assign. Default is the 15th to 31st IP in the guest network,
        i.e. x.x.x.15 to x.x.x.31.

    ``dns=addr``
        Specify the guest-visible address of the virtual nameserver. The
        address must be different from the host address. Default is the
        3rd IP in the guest network, i.e. x.x.x.3.

    ``ipv6-dns=addr``
        Specify the guest-visible address of the IPv6 virtual
        nameserver. The address must be different from the host address.
        Default is the 3rd IP in the guest network, i.e. xxxx::3.

    ``dnssearch=domain``
        Provides an entry for the domain-search list sent by the
        built-in DHCP server. More than one domain suffix can be
        transmitted by specifying this option multiple times. If
        supported, this will cause the guest to automatically try to
        append the given domain suffix(es) in case a domain name can not
        be resolved.

        Example:

        .. parsed-literal::

            |qemu_system| -nic user,dnssearch=mgmt.example.org,dnssearch=example.org

    ``domainname=domain``
        Specifies the client domain name reported by the built-in DHCP
        server.

    ``tftp=dir``
        When using the user mode network stack, activate a built-in TFTP
        server. The files in dir will be exposed as the root of a TFTP
        server. The TFTP client on the guest must be configured in
        binary mode (use the command ``bin`` of the Unix TFTP client).

    ``tftp-server-name=name``
        In BOOTP reply, broadcast name as the "TFTP server name"
        (RFC2132 option 66). This can be used to advise the guest to
        load boot files or configurations from a different server than
        the host address.

    ``bootfile=file``
        When using the user mode network stack, broadcast file as the
        BOOTP filename. In conjunction with ``tftp``, this can be used
        to network boot a guest from a local directory.

        Example (using pxelinux):

        .. parsed-literal::

            |qemu_system| -hda linux.img -boot n -device e1000,netdev=n1 \\
                -netdev user,id=n1,tftp=/path/to/tftp/files,bootfile=/pxelinux.0

    ``smb=dir[,smbserver=addr]``
        When using the user mode network stack, activate a built-in SMB
        server so that Windows OSes can access to the host files in
        ``dir`` transparently. The IP address of the SMB server can be
        set to addr. By default the 4th IP in the guest network is used,
        i.e. x.x.x.4.

        In the guest Windows OS, the line:

        ::

            10.0.2.4 smbserver

        must be added in the file ``C:\WINDOWS\LMHOSTS`` (for windows
        9x/Me) or ``C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS`` (Windows
        NT/2000).

        Then ``dir`` can be accessed in ``\\smbserver\qemu``.

        Note that a SAMBA server must be installed on the host OS.

    ``hostfwd=[tcp|udp]:[hostaddr]:hostport-[guestaddr]:guestport``
        Redirect incoming TCP or UDP connections to the host port
        hostport to the guest IP address guestaddr on guest port
        guestport. If guestaddr is not specified, its value is x.x.x.15
        (default first address given by the built-in DHCP server). By
        specifying hostaddr, the rule can be bound to a specific host
        interface. If no connection type is set, TCP is used. This
        option can be given multiple times.

        For example, to redirect host X11 connection from screen 1 to
        guest screen 0, use the following:

        .. parsed-literal::

            # on the host
            |qemu_system| -nic user,hostfwd=tcp:127.0.0.1:6001-:6000
            # this host xterm should open in the guest X11 server
            xterm -display :1

        To redirect telnet connections from host port 5555 to telnet
        port on the guest, use the following:

        .. parsed-literal::

            # on the host
            |qemu_system| -nic user,hostfwd=tcp::5555-:23
            telnet localhost 5555

        Then when you use on the host ``telnet localhost 5555``, you
        connect to the guest telnet server.

    ``guestfwd=[tcp]:server:port-dev``; \ ``guestfwd=[tcp]:server:port-cmd:command``
        Forward guest TCP connections to the IP address server on port
        port to the character device dev or to a program executed by
        cmd:command which gets spawned for each connection. This option
        can be given multiple times.

        You can either use a chardev directly and have that one used
        throughout QEMU's lifetime, like in the following example:

        .. parsed-literal::

            # open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever
            # the guest accesses it
            |qemu_system| -nic user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321

        Or you can execute a command on every TCP connection established
        by the guest, so that QEMU behaves similar to an inetd process
        for that virtual server:

        .. parsed-literal::

            # call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234
            # and connect the TCP stream to its stdin/stdout
            |qemu_system| -nic  'user,id=n1,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'

``-netdev tap,id=id[,fd=h][,ifname=name][,script=file][,downscript=dfile][,br=bridge][,helper=helper]``
    Configure a host TAP network backend with ID id.

    Use the network script file to configure it and the network script
    dfile to deconfigure it. If name is not provided, the OS
    automatically provides one. The default network configure script is
    ``/etc/qemu-ifup`` and the default network deconfigure script is
    ``/etc/qemu-ifdown``. Use ``script=no`` or ``downscript=no`` to
    disable script execution.

    If running QEMU as an unprivileged user, use the network helper
    to configure the TAP interface and attach it to the bridge.
    The default network helper executable is
    ``/path/to/qemu-bridge-helper`` and the default bridge device is
    ``br0``.

    ``fd``\ =h can be used to specify the handle of an already opened
    host TAP interface.

    Examples:

    .. parsed-literal::

        #launch a QEMU instance with the default network script
        |qemu_system| linux.img -nic tap

    .. parsed-literal::

        #launch a QEMU instance with two NICs, each one connected
        #to a TAP device
        |qemu_system| linux.img \\
                -netdev tap,id=nd0,ifname=tap0 -device e1000,netdev=nd0 \\
                -netdev tap,id=nd1,ifname=tap1 -device rtl8139,netdev=nd1

    .. parsed-literal::

        #launch a QEMU instance with the default network helper to
        #connect a TAP device to bridge br0
        |qemu_system| linux.img -device virtio-net-pci,netdev=n1 \\
                -netdev tap,id=n1,"helper=/path/to/qemu-bridge-helper"

``-netdev bridge,id=id[,br=bridge][,helper=helper]``
    Connect a host TAP network interface to a host bridge device.

    Use the network helper helper to configure the TAP interface and
    attach it to the bridge. The default network helper executable is
    ``/path/to/qemu-bridge-helper`` and the default bridge device is
    ``br0``.

    Examples:

    .. parsed-literal::

        #launch a QEMU instance with the default network helper to
        #connect a TAP device to bridge br0
        |qemu_system| linux.img -netdev bridge,id=n1 -device virtio-net,netdev=n1

    .. parsed-literal::

        #launch a QEMU instance with the default network helper to
        #connect a TAP device to bridge qemubr0
        |qemu_system| linux.img -netdev bridge,br=qemubr0,id=n1 -device virtio-net,netdev=n1

``-netdev socket,id=id[,fd=h][,listen=[host]:port][,connect=host:port]``
    This host network backend can be used to connect the guest's network
    to another QEMU virtual machine using a TCP socket connection. If
    ``listen`` is specified, QEMU waits for incoming connections on port
    (host is optional). ``connect`` is used to connect to another QEMU
    instance using the ``listen`` option. ``fd``\ =h specifies an
    already opened TCP socket.

    Example:

    .. parsed-literal::

        # launch a first QEMU instance
        |qemu_system| linux.img \\
                         -device e1000,netdev=n1,mac=52:54:00:12:34:56 \\
                         -netdev socket,id=n1,listen=:1234
        # connect the network of this instance to the network of the first instance
        |qemu_system| linux.img \\
                         -device e1000,netdev=n2,mac=52:54:00:12:34:57 \\
                         -netdev socket,id=n2,connect=127.0.0.1:1234

``-netdev socket,id=id[,fd=h][,mcast=maddr:port[,localaddr=addr]]``
    Configure a socket host network backend to share the guest's network
    traffic with another QEMU virtual machines using a UDP multicast
    socket, effectively making a bus for every QEMU with same multicast
    address maddr and port. NOTES:

    1. Several QEMU can be running on different hosts and share same bus
       (assuming correct multicast setup for these hosts).

    2. mcast support is compatible with User Mode Linux (argument
       ``ethN=mcast``), see http://user-mode-linux.sf.net.

    3. Use ``fd=h`` to specify an already opened UDP multicast socket.

    Example:

    .. parsed-literal::

        # launch one QEMU instance
        |qemu_system| linux.img \\
                         -device e1000,netdev=n1,mac=52:54:00:12:34:56 \\
                         -netdev socket,id=n1,mcast=230.0.0.1:1234
        # launch another QEMU instance on same "bus"
        |qemu_system| linux.img \\
                         -device e1000,netdev=n2,mac=52:54:00:12:34:57 \\
                         -netdev socket,id=n2,mcast=230.0.0.1:1234
        # launch yet another QEMU instance on same "bus"
        |qemu_system| linux.img \\
                         -device e1000,netdev=n3,mac=52:54:00:12:34:58 \\
                         -netdev socket,id=n3,mcast=230.0.0.1:1234

    Example (User Mode Linux compat.):

    .. parsed-literal::

        # launch QEMU instance (note mcast address selected is UML's default)
        |qemu_system| linux.img \\
                         -device e1000,netdev=n1,mac=52:54:00:12:34:56 \\
                         -netdev socket,id=n1,mcast=239.192.168.1:1102
        # launch UML
        /path/to/linux ubd0=/path/to/root_fs eth0=mcast

    Example (send packets from host's 1.2.3.4):

    .. parsed-literal::

        |qemu_system| linux.img \\
                         -device e1000,netdev=n1,mac=52:54:00:12:34:56 \\
                         -netdev socket,id=n1,mcast=239.192.168.1:1102,localaddr=1.2.3.4

``-netdev l2tpv3,id=id,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport],txsession=txsession[,rxsession=rxsession][,ipv6=on|off][,udp=on|off][,cookie64][,counter][,pincounter][,txcookie=txcookie][,rxcookie=rxcookie][,offset=offset]``
    Configure a L2TPv3 pseudowire host network backend. L2TPv3 (RFC3931)
    is a popular protocol to transport Ethernet (and other Layer 2) data
    frames between two systems. It is present in routers, firewalls and
    the Linux kernel (from version 3.3 onwards).

    This transport allows a VM to communicate to another VM, router or
    firewall directly.

    ``src=srcaddr``
        source address (mandatory)

    ``dst=dstaddr``
        destination address (mandatory)

    ``udp``
        select udp encapsulation (default is ip).

    ``srcport=srcport``
        source udp port.

    ``dstport=dstport``
        destination udp port.

    ``ipv6``
        force v6, otherwise defaults to v4.

    ``rxcookie=rxcookie``; \ ``txcookie=txcookie``
        Cookies are a weak form of security in the l2tpv3 specification.
        Their function is mostly to prevent misconfiguration. By default
        they are 32 bit.

    ``cookie64``
        Set cookie size to 64 bit instead of the default 32

    ``counter=off``
        Force a 'cut-down' L2TPv3 with no counter as in
        draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00

    ``pincounter=on``
        Work around broken counter handling in peer. This may also help
        on networks which have packet reorder.

    ``offset=offset``
        Add an extra offset between header and data

    For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to
    the bridge br-lan on the remote Linux host 1.2.3.4:

    .. parsed-literal::

        # Setup tunnel on linux host using raw ip as encapsulation
        # on 1.2.3.4
        ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \\
            encap udp udp_sport 16384 udp_dport 16384
        ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \\
            0xFFFFFFFF peer_session_id 0xFFFFFFFF
        ifconfig vmtunnel0 mtu 1500
        ifconfig vmtunnel0 up
        brctl addif br-lan vmtunnel0


        # on 4.3.2.1
        # launch QEMU instance - if your network has reorder or is very lossy add ,pincounter

        |qemu_system| linux.img -device e1000,netdev=n1 \\
            -netdev l2tpv3,id=n1,src=4.2.3.1,dst=1.2.3.4,udp,srcport=16384,dstport=16384,rxsession=0xffffffff,txsession=0xffffffff,counter

``-netdev vde,id=id[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]``
    Configure VDE backend to connect to PORT n of a vde switch running
    on host and listening for incoming connections on socketpath. Use
    GROUP groupname and MODE octalmode to change default ownership and
    permissions for communication port. This option is only available if
    QEMU has been compiled with vde support enabled.

    Example:

    .. parsed-literal::

        # launch vde switch
        vde_switch -F -sock /tmp/myswitch
        # launch QEMU instance
        |qemu_system| linux.img -nic vde,sock=/tmp/myswitch

``-netdev vhost-user,chardev=id[,vhostforce=on|off][,queues=n]``
    Establish a vhost-user netdev, backed by a chardev id. The chardev
    should be a unix domain socket backed one. The vhost-user uses a
    specifically defined protocol to pass vhost ioctl replacement
    messages to an application on the other end of the socket. On
    non-MSIX guests, the feature can be forced with vhostforce. Use
    'queues=n' to specify the number of queues to be created for
    multiqueue vhost-user.

    Example:

    ::

        qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \
             -numa node,memdev=mem \
             -chardev socket,id=chr0,path=/path/to/socket \
             -netdev type=vhost-user,id=net0,chardev=chr0 \
             -device virtio-net-pci,netdev=net0

``-netdev vhost-vdpa,vhostdev=/path/to/dev``
    Establish a vhost-vdpa netdev.

    vDPA device is a device that uses a datapath which complies with
    the virtio specifications with a vendor specific control path.
    vDPA devices can be both physically located on the hardware or
    emulated by software.

``-netdev hubport,id=id,hubid=hubid[,netdev=nd]``
    Create a hub port on the emulated hub with ID hubid.

    The hubport netdev lets you connect a NIC to a QEMU emulated hub
    instead of a single netdev. Alternatively, you can also connect the
    hubport to another netdev with ID nd by using the ``netdev=nd``
    option.

``-net nic[,netdev=nd][,macaddr=mac][,model=type] [,name=name][,addr=addr][,vectors=v]``
    Legacy option to configure or create an on-board (or machine
    default) Network Interface Card(NIC) and connect it either to the
    emulated hub with ID 0 (i.e. the default hub), or to the netdev nd.
    If model is omitted, then the default NIC model associated with the
    machine type is used. Note that the default NIC model may change in
    future QEMU releases, so it is highly recommended to always specify
    a model. Optionally, the MAC address can be changed to mac, the
    device address set to addr (PCI cards only), and a name can be
    assigned for use in monitor commands. Optionally, for PCI cards, you
    can specify the number v of MSI-X vectors that the card should have;
    this option currently only affects virtio cards; set v = 0 to
    disable MSI-X. If no ``-net`` option is specified, a single NIC is
    created. QEMU can emulate several different models of network card.
    Use ``-net nic,model=help`` for a list of available devices for your
    target.

``-net user|tap|bridge|socket|l2tpv3|vde[,...][,name=name]``
    Configure a host network backend (with the options corresponding to
    the same ``-netdev`` option) and connect it to the emulated hub 0
    (the default hub). Use name to specify the name of the hub port.
ERST

DEFHEADING()

DEFHEADING(Character device options:)

DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
    "-chardev help\n"
    "-chardev null,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
    "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4=on|off][,ipv6=on|off][,nodelay=on|off]\n"
    "         [,server=on|off][,wait=on|off][,telnet=on|off][,websocket=on|off][,reconnect=seconds][,mux=on|off]\n"
    "         [,logfile=PATH][,logappend=on|off][,tls-creds=ID][,tls-authz=ID] (tcp)\n"
    "-chardev socket,id=id,path=path[,server=on|off][,wait=on|off][,telnet=on|off][,websocket=on|off][,reconnect=seconds]\n"
    "         [,mux=on|off][,logfile=PATH][,logappend=on|off][,abstract=on|off][,tight=on|off] (unix)\n"
    "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
    "         [,localport=localport][,ipv4=on|off][,ipv6=on|off][,mux=on|off]\n"
    "         [,logfile=PATH][,logappend=on|off]\n"
    "-chardev msmouse,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
    "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
    "         [,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
    "-chardev ringbuf,id=id[,size=size][,logfile=PATH][,logappend=on|off]\n"
    "-chardev file,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
    "-chardev pipe,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
#ifdef _WIN32
    "-chardev console,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
    "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
#else
    "-chardev pty,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
    "-chardev stdio,id=id[,mux=on|off][,signal=on|off][,logfile=PATH][,logappend=on|off]\n"
#endif
#ifdef CONFIG_BRLAPI
    "-chardev braille,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
#endif
#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
        || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
    "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
    "-chardev tty,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
#endif
#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
    "-chardev parallel,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
    "-chardev parport,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
#endif
#if defined(CONFIG_SPICE)
    "-chardev spicevmc,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
    "-chardev spiceport,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
#endif
    , QEMU_ARCH_ALL
)

SRST
The general form of a character device option is:

``-chardev backend,id=id[,mux=on|off][,options]``
    Backend is one of: ``null``, ``socket``, ``udp``, ``msmouse``,
    ``vc``, ``ringbuf``, ``file``, ``pipe``, ``console``, ``serial``,
    ``pty``, ``stdio``, ``braille``, ``tty``, ``parallel``, ``parport``,
    ``spicevmc``, ``spiceport``. The specific backend will determine the
    applicable options.

    Use ``-chardev help`` to print all available chardev backend types.

    All devices must have an id, which can be any string up to 127
    characters long. It is used to uniquely identify this device in
    other command line directives.

    A character device may be used in multiplexing mode by multiple
    front-ends. Specify ``mux=on`` to enable this mode. A multiplexer is
    a "1:N" device, and here the "1" end is your specified chardev
    backend, and the "N" end is the various parts of QEMU that can talk
    to a chardev. If you create a chardev with ``id=myid`` and
    ``mux=on``, QEMU will create a multiplexer with your specified ID,
    and you can then configure multiple front ends to use that chardev
    ID for their input/output. Up to four different front ends can be
    connected to a single multiplexed chardev. (Without multiplexing
    enabled, a chardev can only be used by a single front end.) For
    instance you could use this to allow a single stdio chardev to be
    used by two serial ports and the QEMU monitor:

    ::

        -chardev stdio,mux=on,id=char0 \
        -mon chardev=char0,mode=readline \
        -serial chardev:char0 \
        -serial chardev:char0

    You can have more than one multiplexer in a system configuration;
    for instance you could have a TCP port multiplexed between UART 0
    and UART 1, and stdio multiplexed between the QEMU monitor and a
    parallel port:

    ::

        -chardev stdio,mux=on,id=char0 \
        -mon chardev=char0,mode=readline \
        -parallel chardev:char0 \
        -chardev tcp,...,mux=on,id=char1 \
        -serial chardev:char1 \
        -serial chardev:char1

    When you're using a multiplexed character device, some escape
    sequences are interpreted in the input. See the chapter about
    :ref:`keys in the character backend multiplexer` in the
    System Emulation Users Guide for more details.

    Note that some other command line options may implicitly create
    multiplexed character backends; for instance ``-serial mon:stdio``
    creates a multiplexed stdio backend connected to the serial port and
    the QEMU monitor, and ``-nographic`` also multiplexes the console
    and the monitor to stdio.

    There is currently no support for multiplexing in the other
    direction (where a single QEMU front end takes input and output from
    multiple chardevs).

    Every backend supports the ``logfile`` option, which supplies the
    path to a file to record all data transmitted via the backend. The
    ``logappend`` option controls whether the log file will be truncated
    or appended to when opened.

The available backends are:

``-chardev null,id=id``
    A void device. This device will not emit any data, and will drop any
    data it receives. The null backend does not take any options.

``-chardev socket,id=id[,TCP options or unix options][,server=on|off][,wait=on|off][,telnet=on|off][,websocket=on|off][,reconnect=seconds][,tls-creds=id][,tls-authz=id]``
    Create a two-way stream socket, which can be either a TCP or a unix
    socket. A unix socket will be created if ``path`` is specified.
    Behaviour is undefined if TCP options are specified for a unix
    socket.

    ``server=on|off`` specifies that the socket shall be a listening socket.

    ``wait=on|off`` specifies that QEMU should not block waiting for a client
    to connect to a listening socket.

    ``telnet=on|off`` specifies that traffic on the socket should interpret
    telnet escape sequences.

    ``websocket=on|off`` specifies that the socket uses WebSocket protocol for
    communication.

    ``reconnect`` sets the timeout for reconnecting on non-server
    sockets when the remote end goes away. qemu will delay this many
    seconds and then attempt to reconnect. Zero disables reconnecting,
    and is the default.

    ``tls-creds`` requests enablement of the TLS protocol for
    encryption, and specifies the id of the TLS credentials to use for
    the handshake. The credentials must be previously created with the
    ``-object tls-creds`` argument.

    ``tls-auth`` provides the ID of the QAuthZ authorization object
    against which the client's x509 distinguished name will be
    validated. This object is only resolved at time of use, so can be
    deleted and recreated on the fly while the chardev server is active.
    If missing, it will default to denying access.

    TCP and unix socket options are given below:

    ``TCP options: port=port[,host=host][,to=to][,ipv4=on|off][,ipv6=on|off][,nodelay=on|off]``
        ``host`` for a listening socket specifies the local address to
        be bound. For a connecting socket species the remote host to
        connect to. ``host`` is optional for listening sockets. If not
        specified it defaults to ``0.0.0.0``.

        ``port`` for a listening socket specifies the local port to be
        bound. For a connecting socket specifies the port on the remote
        host to connect to. ``port`` can be given as either a port
        number or a service name. ``port`` is required.

        ``to`` is only relevant to listening sockets. If it is
        specified, and ``port`` cannot be bound, QEMU will attempt to
        bind to subsequent ports up to and including ``to`` until it
        succeeds. ``to`` must be specified as a port number.

        ``ipv4=on|off`` and ``ipv6=on|off`` specify that either IPv4
        or IPv6 must be used. If neither is specified the socket may
        use either protocol.

        ``nodelay=on|off`` disables the Nagle algorithm.

    ``unix options: path=path[,abstract=on|off][,tight=on|off]``
        ``path`` specifies the local path of the unix socket. ``path``
        is required.
        ``abstract=on|off`` specifies the use of the abstract socket namespace,
        rather than the filesystem.  Optional, defaults to false.
        ``tight=on|off`` sets the socket length of abstract sockets to their minimum,
        rather than the full sun_path length.  Optional, defaults to true.

``-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr][,localport=localport][,ipv4=on|off][,ipv6=on|off]``
    Sends all traffic from the guest to a remote host over UDP.

    ``host`` specifies the remote host to connect to. If not specified
    it defaults to ``localhost``.

    ``port`` specifies the port on the remote host to connect to.
    ``port`` is required.

    ``localaddr`` specifies the local address to bind to. If not
    specified it defaults to ``0.0.0.0``.

    ``localport`` specifies the local port to bind to. If not specified
    any available local port will be used.

    ``ipv4=on|off`` and ``ipv6=on|off`` specify that either IPv4 or IPv6 must be used.
    If neither is specified the device may use either protocol.

``-chardev msmouse,id=id``
    Forward QEMU's emulated msmouse events to the guest. ``msmouse``
    does not take any options.

``-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]``
    Connect to a QEMU text console. ``vc`` may optionally be given a
    specific size.

    ``width`` and ``height`` specify the width and height respectively
    of the console, in pixels.

    ``cols`` and ``rows`` specify that the console be sized to fit a
    text console with the given dimensions.

``-chardev ringbuf,id=id[,size=size]``
    Create a ring buffer with fixed size ``size``. size must be a power
    of two and defaults to ``64K``.

``-chardev file,id=id,path=path``
    Log all traffic received from the guest to a file.

    ``path`` specifies the path of the file to be opened. This file will
    be created if it does not already exist, and overwritten if it does.
    ``path`` is required.

``-chardev pipe,id=id,path=path``
    Create a two-way connection to the guest. The behaviour differs
    slightly between Windows hosts and other hosts:

    On Windows, a single duplex pipe will be created at
    ``\\.pipe\path``.

    On other hosts, 2 pipes will be created called ``path.in`` and
    ``path.out``. Data written to ``path.in`` will be received by the
    guest. Data written by the guest can be read from ``path.out``. QEMU
    will not create these fifos, and requires them to be present.

    ``path`` forms part of the pipe path as described above. ``path`` is
    required.

``-chardev console,id=id``
    Send traffic from the guest to QEMU's standard output. ``console``
    does not take any options.

    ``console`` is only available on Windows hosts.

``-chardev serial,id=id,path=path``
    Send traffic from the guest to a serial device on the host.

    On Unix hosts serial will actually accept any tty device, not only
    serial lines.

    ``path`` specifies the name of the serial device to open.

``-chardev pty,id=id``
    Create a new pseudo-terminal on the host and connect to it. ``pty``
    does not take any options.

    ``pty`` is not available on Windows hosts.

``-chardev stdio,id=id[,signal=on|off]``
    Connect to standard input and standard output of the QEMU process.

    ``signal`` controls if signals are enabled on the terminal, that
    includes exiting QEMU with the key sequence Control-c. This option
    is enabled by default, use ``signal=off`` to disable it.

``-chardev braille,id=id``
    Connect to a local BrlAPI server. ``braille`` does not take any
    options.

``-chardev tty,id=id,path=path``
    ``tty`` is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD
    and DragonFlyBSD hosts. It is an alias for ``serial``.

    ``path`` specifies the path to the tty. ``path`` is required.

``-chardev parallel,id=id,path=path``
  \
``-chardev parport,id=id,path=path``
    ``parallel`` is only available on Linux, FreeBSD and DragonFlyBSD
    hosts.

    Connect to a local parallel port.

    ``path`` specifies the path to the parallel port device. ``path`` is
    required.

``-chardev spicevmc,id=id,debug=debug,name=name``
    ``spicevmc`` is only available when spice support is built in.

    ``debug`` debug level for spicevmc

    ``name`` name of spice channel to connect to

    Connect to a spice virtual machine channel, such as vdiport.

``-chardev spiceport,id=id,debug=debug,name=name``
    ``spiceport`` is only available when spice support is built in.

    ``debug`` debug level for spicevmc

    ``name`` name of spice port to connect to

    Connect to a spice port, allowing a Spice client to handle the
    traffic identified by a name (preferably a fqdn).
ERST

DEFHEADING()

#ifdef CONFIG_TPM
DEFHEADING(TPM device options:)

DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \
    "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n"
    "                use path to provide path to a character device; default is /dev/tpm0\n"
    "                use cancel-path to provide path to TPM's cancel sysfs entry; if\n"
    "                not provided it will be searched for in /sys/class/misc/tpm?/device\n"
    "-tpmdev emulator,id=id,chardev=dev\n"
    "                configure the TPM device using chardev backend\n",
    QEMU_ARCH_ALL)
SRST
The general form of a TPM device option is:

``-tpmdev backend,id=id[,options]``
    The specific backend type will determine the applicable options. The
    ``-tpmdev`` option creates the TPM backend and requires a
    ``-device`` option that specifies the TPM frontend interface model.

    Use ``-tpmdev help`` to print all available TPM backend types.

The available backends are:

``-tpmdev passthrough,id=id,path=path,cancel-path=cancel-path``
    (Linux-host only) Enable access to the host's TPM using the
    passthrough driver.

    ``path`` specifies the path to the host's TPM device, i.e., on a
    Linux host this would be ``/dev/tpm0``. ``path`` is optional and by
    default ``/dev/tpm0`` is used.

    ``cancel-path`` specifies the path to the host TPM device's sysfs
    entry allowing for cancellation of an ongoing TPM command.
    ``cancel-path`` is optional and by default QEMU will search for the
    sysfs entry to use.

    Some notes about using the host's TPM with the passthrough driver:

    The TPM device accessed by the passthrough driver must not be used
    by any other application on the host.

    Since the host's firmware (BIOS/UEFI) has already initialized the
    TPM, the VM's firmware (BIOS/UEFI) will not be able to initialize
    the TPM again and may therefore not show a TPM-specific menu that
    would otherwise allow the user to configure the TPM, e.g., allow the
    user to enable/disable or activate/deactivate the TPM. Further, if
    TPM ownership is released from within a VM then the host's TPM will
    get disabled and deactivated. To enable and activate the TPM again
    afterwards, the host has to be rebooted and the user is required to
    enter the firmware's menu to enable and activate the TPM. If the TPM
    is left disabled and/or deactivated most TPM commands will fail.

    To create a passthrough TPM use the following two options:

    ::

        -tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0

    Note that the ``-tpmdev`` id is ``tpm0`` and is referenced by
    ``tpmdev=tpm0`` in the device option.

``-tpmdev emulator,id=id,chardev=dev``
    (Linux-host only) Enable access to a TPM emulator using Unix domain
    socket based chardev backend.

    ``chardev`` specifies the unique ID of a character device backend
    that provides connection to the software TPM server.

    To create a TPM emulator backend device with chardev socket backend:

    ::

        -chardev socket,id=chrtpm,path=/tmp/swtpm-sock -tpmdev emulator,id=tpm0,chardev=chrtpm -device tpm-tis,tpmdev=tpm0
ERST

DEFHEADING()

#endif

DEFHEADING(Linux/Multiboot boot specific:)
SRST
When using these options, you can use a given Linux or Multiboot kernel
without installing it in the disk image. It can be useful for easier
testing of various kernels.


ERST

DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \
    "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL)
SRST
``-kernel bzImage``
    Use bzImage as kernel image. The kernel can be either a Linux kernel
    or in multiboot format.
ERST

DEF("append", HAS_ARG, QEMU_OPTION_append, \
    "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL)
SRST
``-append cmdline``
    Use cmdline as kernel command line
ERST

DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \
           "-initrd file    use 'file' as initial ram disk\n", QEMU_ARCH_ALL)
SRST
``-initrd file``
    Use file as initial ram disk.

``-initrd "file1 arg=foo,file2"``
    This syntax is only available with multiboot.

    Use file1 and file2 as modules and pass arg=foo as parameter to the
    first module.
ERST

DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \
    "-dtb    file    use 'file' as device tree image\n", QEMU_ARCH_ALL)
SRST
``-dtb file``
    Use file as a device tree binary (dtb) image and pass it to the
    kernel on boot.
ERST

DEFHEADING()

DEFHEADING(Debug/Expert options:)

DEF("compat", HAS_ARG, QEMU_OPTION_compat,
    "-compat [deprecated-input=accept|reject|crash][,deprecated-output=accept|hide]\n"
    "                Policy for handling deprecated management interfaces\n"
    "-compat [unstable-input=accept|reject|crash][,unstable-output=accept|hide]\n"
    "                Policy for handling unstable management interfaces\n",
    QEMU_ARCH_ALL)
SRST
``-compat [deprecated-input=@var{input-policy}][,deprecated-output=@var{output-policy}]``
    Set policy for handling deprecated management interfaces (experimental):

    ``deprecated-input=accept`` (default)
        Accept deprecated commands and arguments
    ``deprecated-input=reject``
        Reject deprecated commands and arguments
    ``deprecated-input=crash``
        Crash on deprecated commands and arguments
    ``deprecated-output=accept`` (default)
        Emit deprecated command results and events
    ``deprecated-output=hide``
        Suppress deprecated command results and events

    Limitation: covers only syntactic aspects of QMP.

``-compat [unstable-input=@var{input-policy}][,unstable-output=@var{output-policy}]``
    Set policy for handling unstable management interfaces (experimental):

    ``unstable-input=accept`` (default)
        Accept unstable commands and arguments
    ``unstable-input=reject``
        Reject unstable commands and arguments
    ``unstable-input=crash``
        Crash on unstable commands and arguments
    ``unstable-output=accept`` (default)
        Emit unstable command results and events
    ``unstable-output=hide``
        Suppress unstable command results and events

    Limitation: covers only syntactic aspects of QMP.
ERST

DEF("fw_cfg", HAS_ARG, QEMU_OPTION_fwcfg,
    "-fw_cfg [name=]<name>,file=<file>\n"
    "                add named fw_cfg entry with contents from file\n"
    "-fw_cfg [name=]<name>,string=<str>\n"
    "                add named fw_cfg entry with contents from string\n",
    QEMU_ARCH_ALL)
SRST
``-fw_cfg [name=]name,file=file``
    Add named fw\_cfg entry with contents from file file.

``-fw_cfg [name=]name,string=str``
    Add named fw\_cfg entry with contents from string str.

    The terminating NUL character of the contents of str will not be
    included as part of the fw\_cfg item data. To insert contents with
    embedded NUL characters, you have to use the file parameter.

    The fw\_cfg entries are passed by QEMU through to the guest.

    Example:

    ::

            -fw_cfg name=opt/com.mycompany/blob,file=./my_blob.bin

    creates an fw\_cfg entry named opt/com.mycompany/blob with contents
    from ./my\_blob.bin.
ERST

DEF("serial", HAS_ARG, QEMU_OPTION_serial, \
    "-serial dev     redirect the serial port to char device 'dev'\n",
    QEMU_ARCH_ALL)
SRST
``-serial dev``
    Redirect the virtual serial port to host character device dev. The
    default device is ``vc`` in graphical mode and ``stdio`` in non
    graphical mode.

    This option can be used several times to simulate up to 4 serial
    ports.

    Use ``-serial none`` to disable all serial ports.

    Available character devices are:

    ``vc[:WxH]``
        Virtual console. Optionally, a width and height can be given in
        pixel with

        ::

            vc:800x600

        It is also possible to specify width or height in characters:

        ::

            vc:80Cx24C

    ``pty``
        [Linux only] Pseudo TTY (a new PTY is automatically allocated)

    ``none``
        No device is allocated.

    ``null``
        void device

    ``chardev:id``
        Use a named character device defined with the ``-chardev``
        option.

    ``/dev/XXX``
        [Linux only] Use host tty, e.g. ``/dev/ttyS0``. The host serial
        port parameters are set according to the emulated ones.

    ``/dev/parportN``
        [Linux only, parallel port only] Use host parallel port N.
        Currently SPP and EPP parallel port features can be used.

    ``file:filename``
        Write output to filename. No character can be read.

    ``stdio``
        [Unix only] standard input/output

    ``pipe:filename``
        name pipe filename

    ``COMn``
        [Windows only] Use host serial port n

    ``udp:[remote_host]:remote_port[@[src_ip]:src_port]``
        This implements UDP Net Console. When remote\_host or src\_ip
        are not specified they default to ``0.0.0.0``. When not using a
        specified src\_port a random port is automatically chosen.

        If you just want a simple readonly console you can use
        ``netcat`` or ``nc``, by starting QEMU with:
        ``-serial udp::4555`` and nc as: ``nc -u -l -p 4555``. Any time
        QEMU writes something to that port it will appear in the
        netconsole session.

        If you plan to send characters back via netconsole or you want
        to stop and start QEMU a lot of times, you should have QEMU use
        the same source port each time by using something like ``-serial
        udp::4555@:4556`` to QEMU. Another approach is to use a patched
        version of netcat which can listen to a TCP port and send and
        receive characters via udp. If you have a patched version of
        netcat which activates telnet remote echo and single char
        transfer, then you can use the following options to set up a
        netcat redirector to allow telnet on port 5555 to access the
        QEMU port.

        ``QEMU Options:``
            -serial udp::4555@:4556

        ``netcat options:``
            -u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T

        ``telnet options:``
            localhost 5555

    ``tcp:[host]:port[,server=on|off][,wait=on|off][,nodelay=on|off][,reconnect=seconds]``
        The TCP Net Console has two modes of operation. It can send the
        serial I/O to a location or wait for a connection from a
        location. By default the TCP Net Console is sent to host at the
        port. If you use the ``server=on`` option QEMU will wait for a client
        socket application to connect to the port before continuing,
        unless the ``wait=on|off`` option was specified. The ``nodelay=on|off``
        option disables the Nagle buffering algorithm. The ``reconnect=on``
        option only applies if ``server=no`` is set, if the connection goes
        down it will attempt to reconnect at the given interval. If host
        is omitted, 0.0.0.0 is assumed. Only one TCP connection at a
        time is accepted. You can use ``telnet=on`` to connect to the
        corresponding character device.

        ``Example to send tcp console to 192.168.0.2 port 4444``
            -serial tcp:192.168.0.2:4444

        ``Example to listen and wait on port 4444 for connection``
            -serial tcp::4444,server=on

        ``Example to not wait and listen on ip 192.168.0.100 port 4444``
            -serial tcp:192.168.0.100:4444,server=on,wait=off

    ``telnet:host:port[,server=on|off][,wait=on|off][,nodelay=on|off]``
        The telnet protocol is used instead of raw tcp sockets. The
        options work the same as if you had specified ``-serial tcp``.
        The difference is that the port acts like a telnet server or
        client using telnet option negotiation. This will also allow you
        to send the MAGIC\_SYSRQ sequence if you use a telnet that
        supports sending the break sequence. Typically in unix telnet
        you do it with Control-] and then type "send break" followed by
        pressing the enter key.

    ``websocket:host:port,server=on[,wait=on|off][,nodelay=on|off]``
        The WebSocket protocol is used instead of raw tcp socket. The
        port acts as a WebSocket server. Client mode is not supported.

    ``unix:path[,server=on|off][,wait=on|off][,reconnect=seconds]``
        A unix domain socket is used instead of a tcp socket. The option
        works the