diff options
Diffstat (limited to 'Documentation/kernel-parameters.txt')
-rw-r--r-- | Documentation/kernel-parameters.txt | 96 |
1 files changed, 73 insertions, 23 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 6172e4360f6..fd5cac01303 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt | |||
@@ -17,6 +17,12 @@ are specified on the kernel command line with the module name plus | |||
17 | 17 | ||
18 | usbcore.blinkenlights=1 | 18 | usbcore.blinkenlights=1 |
19 | 19 | ||
20 | Hyphens (dashes) and underscores are equivalent in parameter names, so | ||
21 | log_buf_len=1M print-fatal-signals=1 | ||
22 | can also be entered as | ||
23 | log-buf-len=1M print_fatal_signals=1 | ||
24 | |||
25 | |||
20 | This document may not be entirely up to date and comprehensive. The command | 26 | This document may not be entirely up to date and comprehensive. The command |
21 | "modinfo -p ${modulename}" shows a current list of all parameters of a loadable | 27 | "modinfo -p ${modulename}" shows a current list of all parameters of a loadable |
22 | module. Loadable modules, after being loaded into the running kernel, also | 28 | module. Loadable modules, after being loaded into the running kernel, also |
@@ -134,7 +140,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
134 | ./include/asm/setup.h as COMMAND_LINE_SIZE. | 140 | ./include/asm/setup.h as COMMAND_LINE_SIZE. |
135 | 141 | ||
136 | 142 | ||
137 | acpi= [HW,ACPI,X86-64,i386] | 143 | acpi= [HW,ACPI,X86] |
138 | Advanced Configuration and Power Interface | 144 | Advanced Configuration and Power Interface |
139 | Format: { force | off | ht | strict | noirq | rsdt } | 145 | Format: { force | off | ht | strict | noirq | rsdt } |
140 | force -- enable ACPI if default was off | 146 | force -- enable ACPI if default was off |
@@ -218,7 +224,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
218 | acpi_osi="!string2" # remove built-in string2 | 224 | acpi_osi="!string2" # remove built-in string2 |
219 | acpi_osi= # disable all strings | 225 | acpi_osi= # disable all strings |
220 | 226 | ||
221 | acpi_pm_good [X86-32,X86-64] | 227 | acpi_pm_good [X86] |
222 | Override the pmtimer bug detection: force the kernel | 228 | Override the pmtimer bug detection: force the kernel |
223 | to assume that this machine's pmtimer latches its value | 229 | to assume that this machine's pmtimer latches its value |
224 | and always returns good values. | 230 | and always returns good values. |
@@ -231,6 +237,35 @@ and is between 256 and 4096 characters. It is defined in the file | |||
231 | power state again in power transition. | 237 | power state again in power transition. |
232 | 1 : disable the power state check | 238 | 1 : disable the power state check |
233 | 239 | ||
240 | acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode | ||
241 | Format: { level | edge | high | low } | ||
242 | |||
243 | acpi_serialize [HW,ACPI] force serialization of AML methods | ||
244 | |||
245 | acpi_skip_timer_override [HW,ACPI] | ||
246 | Recognize and ignore IRQ0/pin2 Interrupt Override. | ||
247 | For broken nForce2 BIOS resulting in XT-PIC timer. | ||
248 | |||
249 | acpi_sleep= [HW,ACPI] Sleep options | ||
250 | Format: { s3_bios, s3_mode, s3_beep, s4_nohwsig, | ||
251 | old_ordering, s4_nonvs } | ||
252 | See Documentation/power/video.txt for information on | ||
253 | s3_bios and s3_mode. | ||
254 | s3_beep is for debugging; it makes the PC's speaker beep | ||
255 | as soon as the kernel's real-mode entry point is called. | ||
256 | s4_nohwsig prevents ACPI hardware signature from being | ||
257 | used during resume from hibernation. | ||
258 | old_ordering causes the ACPI 1.0 ordering of the _PTS | ||
259 | control method, with respect to putting devices into | ||
260 | low power states, to be enforced (the ACPI 2.0 ordering | ||
261 | of _PTS is used by default). | ||
262 | s4_nonvs prevents the kernel from saving/restoring the | ||
263 | ACPI NVS memory during hibernation. | ||
264 | |||
265 | acpi_use_timer_override [HW,ACPI] | ||
266 | Use timer override. For some broken Nvidia NF5 boards | ||
267 | that require a timer override, but don't have HPET | ||
268 | |||
234 | acpi_enforce_resources= [ACPI] | 269 | acpi_enforce_resources= [ACPI] |
235 | { strict | lax | no } | 270 | { strict | lax | no } |
236 | Check for resource conflicts between native drivers | 271 | Check for resource conflicts between native drivers |
@@ -250,6 +285,9 @@ and is between 256 and 4096 characters. It is defined in the file | |||
250 | ad1848= [HW,OSS] | 285 | ad1848= [HW,OSS] |
251 | Format: <io>,<irq>,<dma>,<dma2>,<type> | 286 | Format: <io>,<irq>,<dma>,<dma2>,<type> |
252 | 287 | ||
288 | add_efi_memmap [EFI; X86] Include EFI memory map in | ||
289 | kernel's map of available physical RAM. | ||
290 | |||
253 | advansys= [HW,SCSI] | 291 | advansys= [HW,SCSI] |
254 | See header of drivers/scsi/advansys.c. | 292 | See header of drivers/scsi/advansys.c. |
255 | 293 | ||
@@ -313,7 +351,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
313 | not play well with APC CPU idle - disable it if you have | 351 | not play well with APC CPU idle - disable it if you have |
314 | APC and your system crashes randomly. | 352 | APC and your system crashes randomly. |
315 | 353 | ||
316 | apic= [APIC,i386] Advanced Programmable Interrupt Controller | 354 | apic= [APIC,X86-32] Advanced Programmable Interrupt Controller |
317 | Change the output verbosity whilst booting | 355 | Change the output verbosity whilst booting |
318 | Format: { quiet (default) | verbose | debug } | 356 | Format: { quiet (default) | verbose | debug } |
319 | Change the amount of debugging information output | 357 | Change the amount of debugging information output |
@@ -459,7 +497,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
459 | Also note the kernel might malfunction if you disable | 497 | Also note the kernel might malfunction if you disable |
460 | some critical bits. | 498 | some critical bits. |
461 | 499 | ||
462 | code_bytes [IA32/X86_64] How many bytes of object code to print | 500 | code_bytes [X86] How many bytes of object code to print |
463 | in an oops report. | 501 | in an oops report. |
464 | Range: 0 - 8192 | 502 | Range: 0 - 8192 |
465 | Default: 64 | 503 | Default: 64 |
@@ -592,7 +630,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
592 | MTRR settings. This parameter disables that behavior, | 630 | MTRR settings. This parameter disables that behavior, |
593 | possibly causing your machine to run very slowly. | 631 | possibly causing your machine to run very slowly. |
594 | 632 | ||
595 | disable_timer_pin_1 [i386,x86-64] | 633 | disable_timer_pin_1 [X86] |
596 | Disable PIN 1 of APIC timer | 634 | Disable PIN 1 of APIC timer |
597 | Can be useful to work around chipset bugs. | 635 | Can be useful to work around chipset bugs. |
598 | 636 | ||
@@ -624,7 +662,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
624 | UART at the specified I/O port or MMIO address. | 662 | UART at the specified I/O port or MMIO address. |
625 | The options are the same as for ttyS, above. | 663 | The options are the same as for ttyS, above. |
626 | 664 | ||
627 | earlyprintk= [X86-32,X86-64,SH,BLACKFIN] | 665 | earlyprintk= [X86,SH,BLACKFIN] |
628 | earlyprintk=vga | 666 | earlyprintk=vga |
629 | earlyprintk=serial[,ttySn[,baudrate]] | 667 | earlyprintk=serial[,ttySn[,baudrate]] |
630 | earlyprintk=dbgp | 668 | earlyprintk=dbgp |
@@ -659,7 +697,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
659 | See Documentation/block/as-iosched.txt and | 697 | See Documentation/block/as-iosched.txt and |
660 | Documentation/block/deadline-iosched.txt for details. | 698 | Documentation/block/deadline-iosched.txt for details. |
661 | 699 | ||
662 | elfcorehdr= [IA64,PPC,SH,X86-32,X86_64] | 700 | elfcorehdr= [IA64,PPC,SH,X86] |
663 | Specifies physical address of start of kernel core | 701 | Specifies physical address of start of kernel core |
664 | image elf header. Generally kexec loader will | 702 | image elf header. Generally kexec loader will |
665 | pass this option to capture kernel. | 703 | pass this option to capture kernel. |
@@ -670,7 +708,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
670 | to discrete, to make X server driver able to add WB | 708 | to discrete, to make X server driver able to add WB |
671 | entry later. This parameter enables that. | 709 | entry later. This parameter enables that. |
672 | 710 | ||
673 | enable_timer_pin_1 [i386,x86-64] | 711 | enable_timer_pin_1 [X86] |
674 | Enable PIN 1 of APIC timer | 712 | Enable PIN 1 of APIC timer |
675 | Can be useful to work around chipset bugs | 713 | Can be useful to work around chipset bugs |
676 | (in particular on some ATI chipsets). | 714 | (in particular on some ATI chipsets). |
@@ -743,7 +781,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
743 | 781 | ||
744 | hashdist= [KNL,NUMA] Large hashes allocated during boot | 782 | hashdist= [KNL,NUMA] Large hashes allocated during boot |
745 | are distributed across NUMA nodes. Defaults on | 783 | are distributed across NUMA nodes. Defaults on |
746 | for IA-64, off otherwise. | 784 | for 64bit NUMA, off otherwise. |
747 | Format: 0 | 1 (for off | on) | 785 | Format: 0 | 1 (for off | on) |
748 | 786 | ||
749 | hcl= [IA-64] SGI's Hardware Graph compatibility layer | 787 | hcl= [IA-64] SGI's Hardware Graph compatibility layer |
@@ -938,7 +976,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
938 | See comment before marvel_specify_io7 in | 976 | See comment before marvel_specify_io7 in |
939 | arch/alpha/kernel/core_marvel.c. | 977 | arch/alpha/kernel/core_marvel.c. |
940 | 978 | ||
941 | io_delay= [X86-32,X86-64] I/O delay method | 979 | io_delay= [X86] I/O delay method |
942 | 0x80 | 980 | 0x80 |
943 | Standard port 0x80 based delay | 981 | Standard port 0x80 based delay |
944 | 0xed | 982 | 0xed |
@@ -1000,7 +1038,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1000 | 1038 | ||
1001 | keepinitrd [HW,ARM] | 1039 | keepinitrd [HW,ARM] |
1002 | 1040 | ||
1003 | kernelcore=nn[KMG] [KNL,X86-32,IA-64,PPC,X86-64] This parameter | 1041 | kernelcore=nn[KMG] [KNL,X86,IA-64,PPC] This parameter |
1004 | specifies the amount of memory usable by the kernel | 1042 | specifies the amount of memory usable by the kernel |
1005 | for non-movable allocations. The requested amount is | 1043 | for non-movable allocations. The requested amount is |
1006 | spread evenly throughout all nodes in the system. The | 1044 | spread evenly throughout all nodes in the system. The |
@@ -1034,7 +1072,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1034 | Configure the RouterBoard 532 series on-chip | 1072 | Configure the RouterBoard 532 series on-chip |
1035 | Ethernet adapter MAC address. | 1073 | Ethernet adapter MAC address. |
1036 | 1074 | ||
1037 | kstack=N [X86-32,X86-64] Print N words from the kernel stack | 1075 | kstack=N [X86] Print N words from the kernel stack |
1038 | in oops dumps. | 1076 | in oops dumps. |
1039 | 1077 | ||
1040 | l2cr= [PPC] | 1078 | l2cr= [PPC] |
@@ -1044,7 +1082,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1044 | lapic [X86-32,APIC] Enable the local APIC even if BIOS | 1082 | lapic [X86-32,APIC] Enable the local APIC even if BIOS |
1045 | disabled it. | 1083 | disabled it. |
1046 | 1084 | ||
1047 | lapic_timer_c2_ok [X86-32,x86-64,APIC] trust the local apic timer | 1085 | lapic_timer_c2_ok [X86,APIC] trust the local apic timer |
1048 | in C2 power state. | 1086 | in C2 power state. |
1049 | 1087 | ||
1050 | libata.dma= [LIBATA] DMA control | 1088 | libata.dma= [LIBATA] DMA control |
@@ -1229,7 +1267,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1229 | [KNL,SH] Allow user to override the default size for | 1267 | [KNL,SH] Allow user to override the default size for |
1230 | per-device physically contiguous DMA buffers. | 1268 | per-device physically contiguous DMA buffers. |
1231 | 1269 | ||
1232 | memmap=exactmap [KNL,X86-32,X86_64] Enable setting of an exact | 1270 | memmap=exactmap [KNL,X86] Enable setting of an exact |
1233 | E820 memory map, as specified by the user. | 1271 | E820 memory map, as specified by the user. |
1234 | Such memmap=exactmap lines can be constructed based on | 1272 | Such memmap=exactmap lines can be constructed based on |
1235 | BIOS output or other requirements. See the memmap=nn@ss | 1273 | BIOS output or other requirements. See the memmap=nn@ss |
@@ -1320,7 +1358,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1320 | mousedev.yres= [MOUSE] Vertical screen resolution, used for devices | 1358 | mousedev.yres= [MOUSE] Vertical screen resolution, used for devices |
1321 | reporting absolute coordinates, such as tablets | 1359 | reporting absolute coordinates, such as tablets |
1322 | 1360 | ||
1323 | movablecore=nn[KMG] [KNL,X86-32,IA-64,PPC,X86-64] This parameter | 1361 | movablecore=nn[KMG] [KNL,X86,IA-64,PPC] This parameter |
1324 | is similar to kernelcore except it specifies the | 1362 | is similar to kernelcore except it specifies the |
1325 | amount of memory used for migratable allocations. | 1363 | amount of memory used for migratable allocations. |
1326 | If both kernelcore and movablecore is specified, | 1364 | If both kernelcore and movablecore is specified, |
@@ -1422,7 +1460,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1422 | when a NMI is triggered. | 1460 | when a NMI is triggered. |
1423 | Format: [state][,regs][,debounce][,die] | 1461 | Format: [state][,regs][,debounce][,die] |
1424 | 1462 | ||
1425 | nmi_watchdog= [KNL,BUGS=X86-32,X86-64] Debugging features for SMP kernels | 1463 | nmi_watchdog= [KNL,BUGS=X86] Debugging features for SMP kernels |
1426 | Format: [panic,][num] | 1464 | Format: [panic,][num] |
1427 | Valid num: 0,1,2 | 1465 | Valid num: 0,1,2 |
1428 | 0 - turn nmi_watchdog off | 1466 | 0 - turn nmi_watchdog off |
@@ -1475,11 +1513,11 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1475 | 1513 | ||
1476 | nodsp [SH] Disable hardware DSP at boot time. | 1514 | nodsp [SH] Disable hardware DSP at boot time. |
1477 | 1515 | ||
1478 | noefi [X86-32,X86-64] Disable EFI runtime services support. | 1516 | noefi [X86] Disable EFI runtime services support. |
1479 | 1517 | ||
1480 | noexec [IA-64] | 1518 | noexec [IA-64] |
1481 | 1519 | ||
1482 | noexec [X86-32,X86-64] | 1520 | noexec [X86] |
1483 | On X86-32 available only on PAE configured kernels. | 1521 | On X86-32 available only on PAE configured kernels. |
1484 | noexec=on: enable non-executable mappings (default) | 1522 | noexec=on: enable non-executable mappings (default) |
1485 | noexec=off: disable non-executable mappings | 1523 | noexec=off: disable non-executable mappings |
@@ -1497,6 +1535,10 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1497 | register save and restore. The kernel will only save | 1535 | register save and restore. The kernel will only save |
1498 | legacy floating-point registers on task switch. | 1536 | legacy floating-point registers on task switch. |
1499 | 1537 | ||
1538 | noxsave [BUGS=X86] Disables x86 extended register state save | ||
1539 | and restore using xsave. The kernel will fallback to | ||
1540 | enabling legacy floating-point and sse state. | ||
1541 | |||
1500 | nohlt [BUGS=ARM,SH] Tells the kernel that the sleep(SH) or | 1542 | nohlt [BUGS=ARM,SH] Tells the kernel that the sleep(SH) or |
1501 | wfi(ARM) instruction doesn't work correctly and not to | 1543 | wfi(ARM) instruction doesn't work correctly and not to |
1502 | use it. This is also useful when using JTAG debugger. | 1544 | use it. This is also useful when using JTAG debugger. |
@@ -1525,7 +1567,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1525 | noirqdebug [X86-32] Disables the code which attempts to detect and | 1567 | noirqdebug [X86-32] Disables the code which attempts to detect and |
1526 | disable unhandled interrupt sources. | 1568 | disable unhandled interrupt sources. |
1527 | 1569 | ||
1528 | no_timer_check [X86-32,X86_64,APIC] Disables the code which tests for | 1570 | no_timer_check [X86,APIC] Disables the code which tests for |
1529 | broken timer IRQ sources. | 1571 | broken timer IRQ sources. |
1530 | 1572 | ||
1531 | noisapnp [ISAPNP] Disables ISA PnP code. | 1573 | noisapnp [ISAPNP] Disables ISA PnP code. |
@@ -1588,6 +1630,8 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1588 | 1630 | ||
1589 | nowb [ARM] | 1631 | nowb [ARM] |
1590 | 1632 | ||
1633 | nox2apic [X86-64,APIC] Do not enable x2APIC mode. | ||
1634 | |||
1591 | nptcg= [IA64] Override max number of concurrent global TLB | 1635 | nptcg= [IA64] Override max number of concurrent global TLB |
1592 | purges which is reported from either PAL_VM_SUMMARY or | 1636 | purges which is reported from either PAL_VM_SUMMARY or |
1593 | SAL PALO. | 1637 | SAL PALO. |
@@ -1689,7 +1733,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1689 | disable the use of PCIE advanced error reporting. | 1733 | disable the use of PCIE advanced error reporting. |
1690 | nodomains [PCI] Disable support for multiple PCI | 1734 | nodomains [PCI] Disable support for multiple PCI |
1691 | root domains (aka PCI segments, in ACPI-speak). | 1735 | root domains (aka PCI segments, in ACPI-speak). |
1692 | nommconf [X86-32,X86_64] Disable use of MMCONFIG for PCI | 1736 | nommconf [X86] Disable use of MMCONFIG for PCI |
1693 | Configuration | 1737 | Configuration |
1694 | nomsi [MSI] If the PCI_MSI kernel config parameter is | 1738 | nomsi [MSI] If the PCI_MSI kernel config parameter is |
1695 | enabled, this kernel boot option can be used to | 1739 | enabled, this kernel boot option can be used to |
@@ -1838,6 +1882,12 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1838 | autoconfiguration. | 1882 | autoconfiguration. |
1839 | Ranges are in pairs (memory base and size). | 1883 | Ranges are in pairs (memory base and size). |
1840 | 1884 | ||
1885 | ports= [IP_VS_FTP] IPVS ftp helper module | ||
1886 | Default is 21. | ||
1887 | Up to 8 (IP_VS_APP_MAX_PORTS) ports | ||
1888 | may be specified. | ||
1889 | Format: <port>,<port>.... | ||
1890 | |||
1841 | print-fatal-signals= | 1891 | print-fatal-signals= |
1842 | [KNL] debug: print fatal signals | 1892 | [KNL] debug: print fatal signals |
1843 | print-fatal-signals=1: print segfault info to | 1893 | print-fatal-signals=1: print segfault info to |
@@ -2380,7 +2430,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
2380 | reported either. | 2430 | reported either. |
2381 | 2431 | ||
2382 | unknown_nmi_panic | 2432 | unknown_nmi_panic |
2383 | [X86-32,X86-64] | 2433 | [X86] |
2384 | Set unknown_nmi_panic=1 early on boot. | 2434 | Set unknown_nmi_panic=1 early on boot. |
2385 | 2435 | ||
2386 | usbcore.autosuspend= | 2436 | usbcore.autosuspend= |
@@ -2447,12 +2497,12 @@ and is between 256 and 4096 characters. It is defined in the file | |||
2447 | medium is write-protected). | 2497 | medium is write-protected). |
2448 | Example: quirks=0419:aaf5:rl,0421:0433:rc | 2498 | Example: quirks=0419:aaf5:rl,0421:0433:rc |
2449 | 2499 | ||
2450 | vdso= [X86-32,SH,x86-64] | 2500 | vdso= [X86,SH] |
2451 | vdso=2: enable compat VDSO (default with COMPAT_VDSO) | 2501 | vdso=2: enable compat VDSO (default with COMPAT_VDSO) |
2452 | vdso=1: enable VDSO (default) | 2502 | vdso=1: enable VDSO (default) |
2453 | vdso=0: disable VDSO mapping | 2503 | vdso=0: disable VDSO mapping |
2454 | 2504 | ||
2455 | vdso32= [X86-32,X86-64] | 2505 | vdso32= [X86] |
2456 | vdso32=2: enable compat VDSO (default with COMPAT_VDSO) | 2506 | vdso32=2: enable compat VDSO (default with COMPAT_VDSO) |
2457 | vdso32=1: enable 32-bit VDSO (default) | 2507 | vdso32=1: enable 32-bit VDSO (default) |
2458 | vdso32=0: disable 32-bit VDSO mapping | 2508 | vdso32=0: disable 32-bit VDSO mapping |