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-rw-r--r--Documentation/kernel-parameters.txt527
1 files changed, 53 insertions, 474 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 363e348bff9..4d5c5650269 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -49,7 +49,6 @@ parameter is applicable:
49 EDD BIOS Enhanced Disk Drive Services (EDD) is enabled 49 EDD BIOS Enhanced Disk Drive Services (EDD) is enabled
50 EFI EFI Partitioning (GPT) is enabled 50 EFI EFI Partitioning (GPT) is enabled
51 EIDE EIDE/ATAPI support is enabled. 51 EIDE EIDE/ATAPI support is enabled.
52 EVM Extended Verification Module
53 FB The frame buffer device is enabled. 52 FB The frame buffer device is enabled.
54 FTRACE Function tracing enabled. 53 FTRACE Function tracing enabled.
55 GCOV GCOV profiling is enabled. 54 GCOV GCOV profiling is enabled.
@@ -70,6 +69,7 @@ parameter is applicable:
70 M68k M68k architecture is enabled. 69 M68k M68k architecture is enabled.
71 These options have more detailed description inside of 70 These options have more detailed description inside of
72 Documentation/m68k/kernel-options.txt. 71 Documentation/m68k/kernel-options.txt.
72 MCA MCA bus support is enabled.
73 MDA MDA console support is enabled. 73 MDA MDA console support is enabled.
74 MIPS MIPS architecture is enabled. 74 MIPS MIPS architecture is enabled.
75 MOUSE Appropriate mouse support is enabled. 75 MOUSE Appropriate mouse support is enabled.
@@ -109,7 +109,6 @@ parameter is applicable:
109 USB USB support is enabled. 109 USB USB support is enabled.
110 USBHID USB Human Interface Device support is enabled. 110 USBHID USB Human Interface Device support is enabled.
111 V4L Video For Linux support is enabled. 111 V4L Video For Linux support is enabled.
112 VMMIO Driver for memory mapped virtio devices is enabled.
113 VGA The VGA console has been enabled. 112 VGA The VGA console has been enabled.
114 VT Virtual terminal support is enabled. 113 VT Virtual terminal support is enabled.
115 WDT Watchdog support is enabled. 114 WDT Watchdog support is enabled.
@@ -164,7 +163,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
164 rsdt -- prefer RSDT over (default) XSDT 163 rsdt -- prefer RSDT over (default) XSDT
165 copy_dsdt -- copy DSDT to memory 164 copy_dsdt -- copy DSDT to memory
166 165
167 See also Documentation/power/runtime_pm.txt, pci=noacpi 166 See also Documentation/power/pm.txt, pci=noacpi
168 167
169 acpi_rsdp= [ACPI,EFI,KEXEC] 168 acpi_rsdp= [ACPI,EFI,KEXEC]
170 Pass the RSDP address to the kernel, mostly used 169 Pass the RSDP address to the kernel, mostly used
@@ -307,20 +306,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
307 behaviour to be specified. Bit 0 enables warnings, 306 behaviour to be specified. Bit 0 enables warnings,
308 bit 1 enables fixups, and bit 2 sends a segfault. 307 bit 1 enables fixups, and bit 2 sends a segfault.
309 308
310 align_va_addr= [X86-64] 309 amd_iommu= [HW,X86-84]
311 Align virtual addresses by clearing slice [14:12] when
312 allocating a VMA at process creation time. This option
313 gives you up to 3% performance improvement on AMD F15h
314 machines (where it is enabled by default) for a
315 CPU-intensive style benchmark, and it can vary highly in
316 a microbenchmark depending on workload and compiler.
317
318 32: only for 32-bit processes
319 64: only for 64-bit processes
320 on: enable for both 32- and 64-bit processes
321 off: disable for both 32- and 64-bit processes
322
323 amd_iommu= [HW,X86-64]
324 Pass parameters to the AMD IOMMU driver in the system. 310 Pass parameters to the AMD IOMMU driver in the system.
325 Possible values are: 311 Possible values are:
326 fullflush - enable flushing of IO/TLB entries when 312 fullflush - enable flushing of IO/TLB entries when
@@ -335,16 +321,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
335 requirements as needed. This option 321 requirements as needed. This option
336 does not override iommu=pt 322 does not override iommu=pt
337 323
338 amd_iommu_dump= [HW,X86-64]
339 Enable AMD IOMMU driver option to dump the ACPI table
340 for AMD IOMMU. With this option enabled, AMD IOMMU
341 driver will print ACPI tables for AMD IOMMU during
342 IOMMU initialization.
343
344 amijoy.map= [HW,JOY] Amiga joystick support 324 amijoy.map= [HW,JOY] Amiga joystick support
345 Map of devices attached to JOY0DAT and JOY1DAT 325 Map of devices attached to JOY0DAT and JOY1DAT
346 Format: <a>,<b> 326 Format: <a>,<b>
347 See also Documentation/input/joystick.txt 327 See also Documentation/kernel/input/joystick.txt
348 328
349 analog.map= [HW,JOY] Analog joystick and gamepad support 329 analog.map= [HW,JOY] Analog joystick and gamepad support
350 Specifies type or capabilities of an analog joystick 330 Specifies type or capabilities of an analog joystick
@@ -403,6 +383,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
403 atkbd.softrepeat= [HW] 383 atkbd.softrepeat= [HW]
404 Use software keyboard repeat 384 Use software keyboard repeat
405 385
386 autotest [IA-64]
387
406 baycom_epp= [HW,AX25] 388 baycom_epp= [HW,AX25]
407 Format: <io>,<mode> 389 Format: <io>,<mode>
408 390
@@ -431,7 +413,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
431 bttv.radio= Most important insmod options are available as 413 bttv.radio= Most important insmod options are available as
432 kernel args too. 414 kernel args too.
433 bttv.pll= See Documentation/video4linux/bttv/Insmod-options 415 bttv.pll= See Documentation/video4linux/bttv/Insmod-options
434 bttv.tuner= 416 bttv.tuner= and Documentation/video4linux/bttv/CARDLIST
435 417
436 bulk_remove=off [PPC] This parameter disables the use of the pSeries 418 bulk_remove=off [PPC] This parameter disables the use of the pSeries
437 firmware feature for flushing multiple hpte entries 419 firmware feature for flushing multiple hpte entries
@@ -446,6 +428,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
446 possible to determine what the correct size should be. 428 possible to determine what the correct size should be.
447 This option provides an override for these situations. 429 This option provides an override for these situations.
448 430
431 capability.disable=
432 [SECURITY] Disable capabilities. This would normally
433 be used only if an alternative security model is to be
434 configured. Potentially dangerous and should only be
435 used if you are entirely sure of the consequences.
436
449 ccw_timeout_log [S390] 437 ccw_timeout_log [S390]
450 See Documentation/s390/CommonIO for details. 438 See Documentation/s390/CommonIO for details.
451 439
@@ -506,11 +494,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
506 Also note the kernel might malfunction if you disable 494 Also note the kernel might malfunction if you disable
507 some critical bits. 495 some critical bits.
508 496
509 cma=nn[MG] [ARM,KNL]
510 Sets the size of kernel global memory area for contiguous
511 memory allocations. For more information, see
512 include/linux/dma-contiguous.h
513
514 cmo_free_hint= [PPC] Format: { yes | no } 497 cmo_free_hint= [PPC] Format: { yes | no }
515 Specify whether pages are marked as being inactive 498 Specify whether pages are marked as being inactive
516 when they are freed. This is used in CMO environments 499 when they are freed. This is used in CMO environments
@@ -518,10 +501,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
518 a hypervisor. 501 a hypervisor.
519 Default: yes 502 Default: yes
520 503
521 coherent_pool=nn[KMG] [ARM,KNL]
522 Sets the size of memory pool for coherent, atomic dma
523 allocations, by default set to 256K.
524
525 code_bytes [X86] How many bytes of object code to print 504 code_bytes [X86] How many bytes of object code to print
526 in an oops report. 505 in an oops report.
527 Range: 0 - 8192 506 Range: 0 - 8192
@@ -617,7 +596,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
617 596
618 ddebug_query= [KNL,DYNAMIC_DEBUG] Enable debug messages at early boot 597 ddebug_query= [KNL,DYNAMIC_DEBUG] Enable debug messages at early boot
619 time. See Documentation/dynamic-debug-howto.txt for 598 time. See Documentation/dynamic-debug-howto.txt for
620 details. Deprecated, see dyndbg. 599 details.
621 600
622 debug [KNL] Enable kernel debugging (events log level). 601 debug [KNL] Enable kernel debugging (events log level).
623 602
@@ -635,25 +614,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
635 no_debug_objects 614 no_debug_objects
636 [KNL] Disable object debugging 615 [KNL] Disable object debugging
637 616
638 debug_guardpage_minorder=
639 [KNL] When CONFIG_DEBUG_PAGEALLOC is set, this
640 parameter allows control of the order of pages that will
641 be intentionally kept free (and hence protected) by the
642 buddy allocator. Bigger value increase the probability
643 of catching random memory corruption, but reduce the
644 amount of memory for normal system use. The maximum
645 possible value is MAX_ORDER/2. Setting this parameter
646 to 1 or 2 should be enough to identify most random
647 memory corruption problems caused by bugs in kernel or
648 driver code when a CPU writes to (or reads from) a
649 random memory location. Note that there exists a class
650 of memory corruptions problems caused by buggy H/W or
651 F/W or by drivers badly programing DMA (basically when
652 memory is written at bus level and the CPU MMU is
653 bypassed) which are not detectable by
654 CONFIG_DEBUG_PAGEALLOC, hence this option will not help
655 tracking down these problems.
656
657 debugpat [X86] Enable PAT debugging 617 debugpat [X86] Enable PAT debugging
658 618
659 decnet.addr= [HW,NET] 619 decnet.addr= [HW,NET]
@@ -720,28 +680,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
720 The filter can be disabled or changed to another 680 The filter can be disabled or changed to another
721 driver later using sysfs. 681 driver later using sysfs.
722 682
723 drm_kms_helper.edid_firmware=[<connector>:]<file>
724 Broken monitors, graphic adapters and KVMs may
725 send no or incorrect EDID data sets. This parameter
726 allows to specify an EDID data set in the
727 /lib/firmware directory that is used instead.
728 Generic built-in EDID data sets are used, if one of
729 edid/1024x768.bin, edid/1280x1024.bin,
730 edid/1680x1050.bin, or edid/1920x1080.bin is given
731 and no file with the same name exists. Details and
732 instructions how to build your own EDID data are
733 available in Documentation/EDID/HOWTO.txt. An EDID
734 data set will only be used for a particular connector,
735 if its name and a colon are prepended to the EDID
736 name.
737
738 dscc4.setup= [NET] 683 dscc4.setup= [NET]
739 684
740 dyndbg[="val"] [KNL,DYNAMIC_DEBUG]
741 module.dyndbg[="val"]
742 Enable debug messages at boot time. See
743 Documentation/dynamic-debug-howto.txt for details.
744
745 earlycon= [KNL] Output early console device and options. 685 earlycon= [KNL] Output early console device and options.
746 uart[8250],io,<addr>[,options] 686 uart[8250],io,<addr>[,options]
747 uart[8250],mmio,<addr>[,options] 687 uart[8250],mmio,<addr>[,options]
@@ -789,13 +729,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
789 729
790 elevator= [IOSCHED] 730 elevator= [IOSCHED]
791 Format: {"cfq" | "deadline" | "noop"} 731 Format: {"cfq" | "deadline" | "noop"}
792 See Documentation/block/cfq-iosched.txt and 732 See Documentation/block/as-iosched.txt and
793 Documentation/block/deadline-iosched.txt for details. 733 Documentation/block/deadline-iosched.txt for details.
794 734
795 elfcorehdr=[size[KMG]@]offset[KMG] [IA64,PPC,SH,X86,S390] 735 elfcorehdr= [IA-64,PPC,SH,X86]
796 Specifies physical address of start of kernel core 736 Specifies physical address of start of kernel core
797 image elf header and optionally the size. Generally 737 image elf header. Generally kexec loader will
798 kexec loader will pass this option to capture kernel. 738 pass this option to capture kernel.
799 See Documentation/kdump/kdump.txt for details. 739 See Documentation/kdump/kdump.txt for details.
800 740
801 enable_mtrr_cleanup [X86] 741 enable_mtrr_cleanup [X86]
@@ -825,17 +765,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
825 This option is obsoleted by the "netdev=" option, which 765 This option is obsoleted by the "netdev=" option, which
826 has equivalent usage. See its documentation for details. 766 has equivalent usage. See its documentation for details.
827 767
828 evm= [EVM]
829 Format: { "fix" }
830 Permit 'security.evm' to be updated regardless of
831 current integrity status.
832
833 failslab= 768 failslab=
834 fail_page_alloc= 769 fail_page_alloc=
835 fail_make_request=[KNL] 770 fail_make_request=[KNL]
836 General fault injection mechanism. 771 General fault injection mechanism.
837 Format: <interval>,<probability>,<space>,<times> 772 Format: <interval>,<probability>,<space>,<times>
838 See also Documentation/fault-injection/. 773 See also /Documentation/fault-injection/.
839 774
840 floppy= [HW] 775 floppy= [HW]
841 See Documentation/blockdev/floppy.txt. 776 See Documentation/blockdev/floppy.txt.
@@ -899,24 +834,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
899 gpt [EFI] Forces disk with valid GPT signature but 834 gpt [EFI] Forces disk with valid GPT signature but
900 invalid Protective MBR to be treated as GPT. 835 invalid Protective MBR to be treated as GPT.
901 836
902 grcan.enable0= [HW] Configuration of physical interface 0. Determines
903 the "Enable 0" bit of the configuration register.
904 Format: 0 | 1
905 Default: 0
906 grcan.enable1= [HW] Configuration of physical interface 1. Determines
907 the "Enable 0" bit of the configuration register.
908 Format: 0 | 1
909 Default: 0
910 grcan.select= [HW] Select which physical interface to use.
911 Format: 0 | 1
912 Default: 0
913 grcan.txsize= [HW] Sets the size of the tx buffer.
914 Format: <unsigned int> such that (txsize & ~0x1fffc0) == 0.
915 Default: 1024
916 grcan.rxsize= [HW] Sets the size of the rx buffer.
917 Format: <unsigned int> such that (rxsize & ~0x1fffc0) == 0.
918 Default: 1024
919
920 hashdist= [KNL,NUMA] Large hashes allocated during boot 837 hashdist= [KNL,NUMA] Large hashes allocated during boot
921 are distributed across NUMA nodes. Defaults on 838 are distributed across NUMA nodes. Defaults on
922 for 64-bit NUMA, off otherwise. 839 for 64-bit NUMA, off otherwise.
@@ -995,7 +912,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
995 controller 912 controller
996 i8042.nopnp [HW] Don't use ACPIPnP / PnPBIOS to discover KBD/AUX 913 i8042.nopnp [HW] Don't use ACPIPnP / PnPBIOS to discover KBD/AUX
997 controllers 914 controllers
998 i8042.notimeout [HW] Ignore timeout condition signalled by controller 915 i8042.notimeout [HW] Ignore timeout condition signalled by conroller
999 i8042.reset [HW] Reset the controller during init and cleanup 916 i8042.reset [HW] Reset the controller during init and cleanup
1000 i8042.unlock [HW] Unlock (ignore) the keylock 917 i8042.unlock [HW] Unlock (ignore) the keylock
1001 918
@@ -1012,20 +929,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
1012 i8k.restricted [HW] Allow controlling fans only if SYS_ADMIN 929 i8k.restricted [HW] Allow controlling fans only if SYS_ADMIN
1013 capability is set. 930 capability is set.
1014 931
1015 i915.invert_brightness=
1016 [DRM] Invert the sense of the variable that is used to
1017 set the brightness of the panel backlight. Normally a
1018 brightness value of 0 indicates backlight switched off,
1019 and the maximum of the brightness value sets the backlight
1020 to maximum brightness. If this parameter is set to 0
1021 (default) and the machine requires it, or this parameter
1022 is set to 1, a brightness value of 0 sets the backlight
1023 to maximum brightness, and the maximum of the brightness
1024 value switches the backlight off.
1025 -1 -- never invert brightness
1026 0 -- machine default
1027 1 -- force brightness inversion
1028
1029 icn= [HW,ISDN] 932 icn= [HW,ISDN]
1030 Format: <io>[,<membase>[,<icn_id>[,<icn_id2>]]] 933 Format: <io>[,<membase>[,<icn_id>[,<icn_id2>]]]
1031 934
@@ -1056,21 +959,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
1056 ignore_loglevel [KNL] 959 ignore_loglevel [KNL]
1057 Ignore loglevel setting - this will print /all/ 960 Ignore loglevel setting - this will print /all/
1058 kernel messages to the console. Useful for debugging. 961 kernel messages to the console. Useful for debugging.
1059 We also add it as printk module parameter, so users
1060 could change it dynamically, usually by
1061 /sys/module/printk/parameters/ignore_loglevel.
1062 962
1063 ihash_entries= [KNL] 963 ihash_entries= [KNL]
1064 Set number of hash buckets for inode cache. 964 Set number of hash buckets for inode cache.
1065 965
1066 ima_appraise= [IMA] appraise integrity measurements
1067 Format: { "off" | "enforce" | "fix" }
1068 default: "enforce"
1069
1070 ima_appraise_tcb [IMA]
1071 The builtin appraise policy appraises all files
1072 owned by uid=0.
1073
1074 ima_audit= [IMA] 966 ima_audit= [IMA]
1075 Format: { "0" | "1" } 967 Format: { "0" | "1" }
1076 0 -- integrity auditing messages. (Default) 968 0 -- integrity auditing messages. (Default)
@@ -1126,11 +1018,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
1126 By default, super page will be supported if Intel IOMMU 1018 By default, super page will be supported if Intel IOMMU
1127 has the capability. With this option, super page will 1019 has the capability. With this option, super page will
1128 not be supported. 1020 not be supported.
1129
1130 intel_idle.max_cstate= [KNL,HW,ACPI,X86]
1131 0 disables intel_idle and fall back on acpi_idle.
1132 1 to 6 specify maximum depth of C-state.
1133
1134 intremap= [X86-64, Intel-IOMMU] 1021 intremap= [X86-64, Intel-IOMMU]
1135 on enable Interrupt Remapping (default) 1022 on enable Interrupt Remapping (default)
1136 off disable Interrupt Remapping 1023 off disable Interrupt Remapping
@@ -1138,6 +1025,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
1138 no_x2apic_optout 1025 no_x2apic_optout
1139 BIOS x2APIC opt-out request will be ignored 1026 BIOS x2APIC opt-out request will be ignored
1140 1027
1028 inttest= [IA-64]
1029
1141 iomem= Disable strict checking of access to MMIO memory 1030 iomem= Disable strict checking of access to MMIO memory
1142 strict regions from userspace. 1031 strict regions from userspace.
1143 relaxed 1032 relaxed
@@ -1154,6 +1043,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
1154 forcesac 1043 forcesac
1155 soft 1044 soft
1156 pt [x86, IA-64] 1045 pt [x86, IA-64]
1046 group_mf [x86, IA-64]
1157 1047
1158 1048
1159 io7= [HW] IO7 for Marvel based alpha systems 1049 io7= [HW] IO7 for Marvel based alpha systems
@@ -1273,6 +1163,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
1273 kvm.ignore_msrs=[KVM] Ignore guest accesses to unhandled MSRs. 1163 kvm.ignore_msrs=[KVM] Ignore guest accesses to unhandled MSRs.
1274 Default is 0 (don't ignore, but inject #GP) 1164 Default is 0 (don't ignore, but inject #GP)
1275 1165
1166 kvm.oos_shadow= [KVM] Disable out-of-sync shadow paging.
1167 Default is 1 (enabled)
1168
1276 kvm.mmu_audit= [KVM] This is a R/W parameter which allows audit 1169 kvm.mmu_audit= [KVM] This is a R/W parameter which allows audit
1277 KVM MMU at runtime. 1170 KVM MMU at runtime.
1278 Default is 0 (off) 1171 Default is 0 (off)
@@ -1296,10 +1189,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
1296 [KVM,Intel] Disable FlexPriority feature (TPR shadow). 1189 [KVM,Intel] Disable FlexPriority feature (TPR shadow).
1297 Default is 1 (enabled) 1190 Default is 1 (enabled)
1298 1191
1299 kvm-intel.nested=
1300 [KVM,Intel] Enable VMX nesting (nVMX).
1301 Default is 0 (disabled)
1302
1303 kvm-intel.unrestricted_guest= 1192 kvm-intel.unrestricted_guest=
1304 [KVM,Intel] Disable unrestricted guest feature 1193 [KVM,Intel] Disable unrestricted guest feature
1305 (virtualized real and unpaged mode) on capable 1194 (virtualized real and unpaged mode) on capable
@@ -1316,10 +1205,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
1316 lapic [X86-32,APIC] Enable the local APIC even if BIOS 1205 lapic [X86-32,APIC] Enable the local APIC even if BIOS
1317 disabled it. 1206 disabled it.
1318 1207
1319 lapic= [x86,APIC] "notscdeadline" Do not use TSC deadline
1320 value for LAPIC timer one-shot implementation. Default
1321 back to the programmable timer unit in the LAPIC.
1322
1323 lapic_timer_c2_ok [X86,APIC] trust the local apic timer 1208 lapic_timer_c2_ok [X86,APIC] trust the local apic timer
1324 in C2 power state. 1209 in C2 power state.
1325 1210
@@ -1374,9 +1259,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
1374 * nohrst, nosrst, norst: suppress hard, soft 1259 * nohrst, nosrst, norst: suppress hard, soft
1375 and both resets. 1260 and both resets.
1376 1261
1377 * rstonce: only attempt one reset during
1378 hot-unplug link recovery
1379
1380 * dump_id: dump IDENTIFY data. 1262 * dump_id: dump IDENTIFY data.
1381 1263
1382 If there are multiple matching configurations changing 1264 If there are multiple matching configurations changing
@@ -1483,6 +1365,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
1483 devices can be requested on-demand with the 1365 devices can be requested on-demand with the
1484 /dev/loop-control interface. 1366 /dev/loop-control interface.
1485 1367
1368 mcatest= [IA-64]
1369
1486 mce [X86-32] Machine Check Exception 1370 mce [X86-32] Machine Check Exception
1487 1371
1488 mce=option [X86-64] See Documentation/x86/x86_64/boot-options.txt 1372 mce=option [X86-64] See Documentation/x86/x86_64/boot-options.txt
@@ -1497,10 +1381,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
1497 mem=nn[KMG] [KNL,BOOT] Force usage of a specific amount of memory 1381 mem=nn[KMG] [KNL,BOOT] Force usage of a specific amount of memory
1498 Amount of memory to be used when the kernel is not able 1382 Amount of memory to be used when the kernel is not able
1499 to see the whole system memory or for test. 1383 to see the whole system memory or for test.
1500 [X86] Work as limiting max address. Use together 1384 [X86-32] Use together with memmap= to avoid physical
1501 with memmap= to avoid physical address space collisions. 1385 address space collisions. Without memmap= PCI devices
1502 Without memmap= PCI devices could be placed at addresses 1386 could be placed at addresses belonging to unused RAM.
1503 belonging to unused RAM.
1504 1387
1505 mem=nopentium [BUGS=X86-32] Disable usage of 4MB pages for kernel 1388 mem=nopentium [BUGS=X86-32] Disable usage of 4MB pages for kernel
1506 memory. 1389 memory.
@@ -1610,12 +1493,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
1610 log everything. Information is printed at KERN_DEBUG 1493 log everything. Information is printed at KERN_DEBUG
1611 so loglevel=8 may also need to be specified. 1494 so loglevel=8 may also need to be specified.
1612 1495
1613 module.sig_enforce
1614 [KNL] When CONFIG_MODULE_SIG is set, this means that
1615 modules without (valid) signatures will fail to load.
1616 Note that if CONFIG_MODULE_SIG_ENFORCE is set, that
1617 is always true, so this option does nothing.
1618
1619 mousedev.tap_time= 1496 mousedev.tap_time=
1620 [MOUSE] Maximum time between finger touching and 1497 [MOUSE] Maximum time between finger touching and
1621 leaving touchpad surface for touch to be considered 1498 leaving touchpad surface for touch to be considered
@@ -1733,52 +1610,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
1733 of returning the full 64-bit number. 1610 of returning the full 64-bit number.
1734 The default is to return 64-bit inode numbers. 1611 The default is to return 64-bit inode numbers.
1735 1612
1736 nfs.max_session_slots=
1737 [NFSv4.1] Sets the maximum number of session slots
1738 the client will attempt to negotiate with the server.
1739 This limits the number of simultaneous RPC requests
1740 that the client can send to the NFSv4.1 server.
1741 Note that there is little point in setting this
1742 value higher than the max_tcp_slot_table_limit.
1743
1744 nfs.nfs4_disable_idmapping= 1613 nfs.nfs4_disable_idmapping=
1745 [NFSv4] When set to the default of '1', this option 1614 [NFSv4] When set, this option disables the NFSv4
1746 ensures that both the RPC level authentication 1615 idmapper on the client, but only if the mount
1747 scheme and the NFS level operations agree to use 1616 is using the 'sec=sys' security flavour. This may
1748 numeric uids/gids if the mount is using the 1617 make migration from legacy NFSv2/v3 systems easier
1749 'sec=sys' security flavour. In effect it is 1618 provided that the server has the appropriate support.
1750 disabling idmapping, which can make migration from 1619 The default is to always enable NFSv4 idmapping.
1751 legacy NFSv2/v3 systems to NFSv4 easier.
1752 Servers that do not support this mode of operation
1753 will be autodetected by the client, and it will fall
1754 back to using the idmapper.
1755 To turn off this behaviour, set the value to '0'.
1756 nfs.nfs4_unique_id=
1757 [NFS4] Specify an additional fixed unique ident-
1758 ification string that NFSv4 clients can insert into
1759 their nfs_client_id4 string. This is typically a
1760 UUID that is generated at system install time.
1761
1762 nfs.send_implementation_id =
1763 [NFSv4.1] Send client implementation identification
1764 information in exchange_id requests.
1765 If zero, no implementation identification information
1766 will be sent.
1767 The default is to send the implementation identification
1768 information.
1769
1770 nfsd.nfs4_disable_idmapping=
1771 [NFSv4] When set to the default of '1', the NFSv4
1772 server will return only numeric uids and gids to
1773 clients using auth_sys, and will accept numeric uids
1774 and gids from such clients. This is intended to ease
1775 migration from NFSv2/v3.
1776
1777 objlayoutdriver.osd_login_prog=
1778 [NFS] [OBJLAYOUT] sets the pathname to the program which
1779 is used to automatically discover and login into new
1780 osd-targets. Please see:
1781 Documentation/filesystems/pnfs.txt for more explanations
1782 1620
1783 nmi_debug= [KNL,AVR32,SH] Specify one or more actions to take 1621 nmi_debug= [KNL,AVR32,SH] Specify one or more actions to take
1784 when a NMI is triggered. 1622 when a NMI is triggered.
@@ -1812,11 +1650,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
1812 debugging driver suspend/resume hooks). This may 1650 debugging driver suspend/resume hooks). This may
1813 not work reliably with all consoles, but is known 1651 not work reliably with all consoles, but is known
1814 to work with serial and VGA consoles. 1652 to work with serial and VGA consoles.
1815 To facilitate more flexible debugging, we also add
1816 console_suspend, a printk module parameter to control
1817 it. Users could use console_suspend (usually
1818 /sys/module/printk/parameters/console_suspend) to
1819 turn on/off it dynamically.
1820 1653
1821 noaliencache [MM, NUMA, SLAB] Disables the allocation of alien 1654 noaliencache [MM, NUMA, SLAB] Disables the allocation of alien
1822 caches in the slab allocator. Saves per-node memory, 1655 caches in the slab allocator. Saves per-node memory,
@@ -1851,12 +1684,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
1851 noexec=on: enable non-executable mappings (default) 1684 noexec=on: enable non-executable mappings (default)
1852 noexec=off: disable non-executable mappings 1685 noexec=off: disable non-executable mappings
1853 1686
1854 nosmap [X86]
1855 Disable SMAP (Supervisor Mode Access Prevention)
1856 even if it is supported by processor.
1857
1858 nosmep [X86] 1687 nosmep [X86]
1859 Disable SMEP (Supervisor Mode Execution Prevention) 1688 Disable SMEP (Supervisor Mode Execution Protection)
1860 even if it is supported by processor. 1689 even if it is supported by processor.
1861 1690
1862 noexec32 [X86-64] 1691 noexec32 [X86-64]
@@ -1876,12 +1705,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
1876 and restore using xsave. The kernel will fallback to 1705 and restore using xsave. The kernel will fallback to
1877 enabling legacy floating-point and sse state. 1706 enabling legacy floating-point and sse state.
1878 1707
1879 eagerfpu= [X86]
1880 on enable eager fpu restore
1881 off disable eager fpu restore
1882 auto selects the default scheme, which automatically
1883 enables eagerfpu restore for xsaveopt.
1884
1885 nohlt [BUGS=ARM,SH] Tells the kernel that the sleep(SH) or 1708 nohlt [BUGS=ARM,SH] Tells the kernel that the sleep(SH) or
1886 wfi(ARM) instruction doesn't work correctly and not to 1709 wfi(ARM) instruction doesn't work correctly and not to
1887 use it. This is also useful when using JTAG debugger. 1710 use it. This is also useful when using JTAG debugger.
@@ -1949,12 +1772,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
1949 nomfgpt [X86-32] Disable Multi-Function General Purpose 1772 nomfgpt [X86-32] Disable Multi-Function General Purpose
1950 Timer usage (for AMD Geode machines). 1773 Timer usage (for AMD Geode machines).
1951 1774
1952 nonmi_ipi [X86] Disable using NMI IPIs during panic/reboot to
1953 shutdown the other cpus. Instead use the REBOOT_VECTOR
1954 irq.
1955
1956 nomodule Disable module load
1957
1958 nopat [X86] Disable PAT (page attribute table extension of 1775 nopat [X86] Disable PAT (page attribute table extension of
1959 pagetables) support. 1776 pagetables) support.
1960 1777
@@ -1968,11 +1785,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
1968 1785
1969 noresidual [PPC] Don't use residual data on PReP machines. 1786 noresidual [PPC] Don't use residual data on PReP machines.
1970 1787
1971 nordrand [X86] Disable the direct use of the RDRAND
1972 instruction even if it is supported by the
1973 processor. RDRAND is still available to user
1974 space applications.
1975
1976 noresume [SWSUSP] Disables resume and restores original swap 1788 noresume [SWSUSP] Disables resume and restores original swap
1977 space. 1789 space.
1978 1790
@@ -2001,20 +1813,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
2001 1813
2002 nox2apic [X86-64,APIC] Do not enable x2APIC mode. 1814 nox2apic [X86-64,APIC] Do not enable x2APIC mode.
2003 1815
2004 cpu0_hotplug [X86] Turn on CPU0 hotplug feature when
2005 CONFIG_BOOTPARAM_HOTPLUG_CPU0 is off.
2006 Some features depend on CPU0. Known dependencies are:
2007 1. Resume from suspend/hibernate depends on CPU0.
2008 Suspend/hibernate will fail if CPU0 is offline and you
2009 need to online CPU0 before suspend/hibernate.
2010 2. PIC interrupts also depend on CPU0. CPU0 can't be
2011 removed if a PIC interrupt is detected.
2012 It's said poweroff/reboot may depend on CPU0 on some
2013 machines although I haven't seen such issues so far
2014 after CPU0 is offline on a few tested machines.
2015 If the dependencies are under your control, you can
2016 turn on cpu0_hotplug.
2017
2018 nptcg= [IA-64] Override max number of concurrent global TLB 1816 nptcg= [IA-64] Override max number of concurrent global TLB
2019 purges which is reported from either PAL_VM_SUMMARY or 1817 purges which is reported from either PAL_VM_SUMMARY or
2020 SAL PALO. 1818 SAL PALO.
@@ -2027,9 +1825,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
2027 1825
2028 nr_uarts= [SERIAL] maximum number of UARTs to be registered. 1826 nr_uarts= [SERIAL] maximum number of UARTs to be registered.
2029 1827
2030 numa_balancing= [KNL,X86] Enable or disable automatic NUMA balancing.
2031 Allowed values are enable and disable
2032
2033 numa_zonelist_order= [KNL, BOOT] Select zonelist order for NUMA. 1828 numa_zonelist_order= [KNL, BOOT] Select zonelist order for NUMA.
2034 one of ['zone', 'node', 'default'] can be specified 1829 one of ['zone', 'node', 'default'] can be specified
2035 This can be set from sysctl after boot. 1830 This can be set from sysctl after boot.
@@ -2061,11 +1856,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
2061 arch_perfmon: [X86] Force use of architectural 1856 arch_perfmon: [X86] Force use of architectural
2062 perfmon on Intel CPUs instead of the 1857 perfmon on Intel CPUs instead of the
2063 CPU specific event set. 1858 CPU specific event set.
2064 timer: [X86] Force use of architectural NMI
2065 timer mode (see also oprofile.timer
2066 for generic hr timer mode)
2067 [s390] Force legacy basic mode sampling
2068 (report cpu_type "timer")
2069 1859
2070 oops=panic Always panic on oopses. Default is to just kill the 1860 oops=panic Always panic on oopses. Default is to just kill the
2071 process, but there is a small probability of 1861 process, but there is a small probability of
@@ -2248,17 +2038,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
2248 the default. 2038 the default.
2249 off: Turn ECRC off 2039 off: Turn ECRC off
2250 on: Turn ECRC on. 2040 on: Turn ECRC on.
2251 realloc= Enable/disable reallocating PCI bridge resources 2041 realloc reallocate PCI resources if allocations done by BIOS
2252 if allocations done by BIOS are too small to 2042 are erroneous.
2253 accommodate resources required by all child
2254 devices.
2255 off: Turn realloc off
2256 on: Turn realloc on
2257 realloc same as realloc=on
2258 noari do not use PCIe ARI.
2259 pcie_scan_all Scan all possible PCIe devices. Otherwise we
2260 only look for one device below a PCIe downstream
2261 port.
2262 2043
2263 pcie_aspm= [PCIE] Forcibly enable or disable PCIe Active State Power 2044 pcie_aspm= [PCIE] Forcibly enable or disable PCIe Active State Power
2264 Management. 2045 Management.
@@ -2266,10 +2047,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
2266 force Enable ASPM even on devices that claim not to support it. 2047 force Enable ASPM even on devices that claim not to support it.
2267 WARNING: Forcing ASPM on may cause system lockups. 2048 WARNING: Forcing ASPM on may cause system lockups.
2268 2049
2269 pcie_hp= [PCIE] PCI Express Hotplug driver options:
2270 nomsi Do not use MSI for PCI Express Native Hotplug (this
2271 makes all PCIe ports use INTx for hotplug services).
2272
2273 pcie_ports= [PCIE] PCIe ports handling: 2050 pcie_ports= [PCIE] PCIe ports handling:
2274 auto Ask the BIOS whether or not to use native PCIe services 2051 auto Ask the BIOS whether or not to use native PCIe services
2275 associated with PCIe ports (PME, hot-plug, AER). Use 2052 associated with PCIe ports (PME, hot-plug, AER). Use
@@ -2363,12 +2140,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
2363 2140
2364 default: off. 2141 default: off.
2365 2142
2366 printk.always_kmsg_dump=
2367 Trigger kmsg_dump for cases other than kernel oops or
2368 panics
2369 Format: <bool> (1/Y/y=enable, 0/N/n=disable)
2370 default: disabled
2371
2372 printk.time= Show timing data prefixed to each printk message line 2143 printk.time= Show timing data prefixed to each printk message line
2373 Format: <bool> (1/Y/y=enable, 0/N/n=disable) 2144 Format: <bool> (1/Y/y=enable, 0/N/n=disable)
2374 2145
@@ -2428,137 +2199,18 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
2428 ramdisk_size= [RAM] Sizes of RAM disks in kilobytes 2199 ramdisk_size= [RAM] Sizes of RAM disks in kilobytes
2429 See Documentation/blockdev/ramdisk.txt. 2200 See Documentation/blockdev/ramdisk.txt.
2430 2201
2431 rcu_nocbs= [KNL,BOOT] 2202 rcupdate.blimit= [KNL,BOOT]
2432 In kernels built with CONFIG_RCU_NOCB_CPU=y, set
2433 the specified list of CPUs to be no-callback CPUs.
2434 Invocation of these CPUs' RCU callbacks will
2435 be offloaded to "rcuoN" kthreads created for
2436 that purpose. This reduces OS jitter on the
2437 offloaded CPUs, which can be useful for HPC and
2438 real-time workloads. It can also improve energy
2439 efficiency for asymmetric multiprocessors.
2440
2441 rcu_nocbs_poll [KNL,BOOT]
2442 Rather than requiring that offloaded CPUs
2443 (specified by rcu_nocbs= above) explicitly
2444 awaken the corresponding "rcuoN" kthreads,
2445 make these kthreads poll for callbacks.
2446 This improves the real-time response for the
2447 offloaded CPUs by relieving them of the need to
2448 wake up the corresponding kthread, but degrades
2449 energy efficiency by requiring that the kthreads
2450 periodically wake up to do the polling.
2451
2452 rcutree.blimit= [KNL,BOOT]
2453 Set maximum number of finished RCU callbacks to process 2203 Set maximum number of finished RCU callbacks to process
2454 in one batch. 2204 in one batch.
2455 2205
2456 rcutree.fanout_leaf= [KNL,BOOT] 2206 rcupdate.qhimark= [KNL,BOOT]
2457 Increase the number of CPUs assigned to each
2458 leaf rcu_node structure. Useful for very large
2459 systems.
2460
2461 rcutree.qhimark= [KNL,BOOT]
2462 Set threshold of queued 2207 Set threshold of queued
2463 RCU callbacks over which batch limiting is disabled. 2208 RCU callbacks over which batch limiting is disabled.
2464 2209
2465 rcutree.qlowmark= [KNL,BOOT] 2210 rcupdate.qlowmark= [KNL,BOOT]
2466 Set threshold of queued RCU callbacks below which 2211 Set threshold of queued RCU callbacks below which
2467 batch limiting is re-enabled. 2212 batch limiting is re-enabled.
2468 2213
2469 rcutree.rcu_cpu_stall_suppress= [KNL,BOOT]
2470 Suppress RCU CPU stall warning messages.
2471
2472 rcutree.rcu_cpu_stall_timeout= [KNL,BOOT]
2473 Set timeout for RCU CPU stall warning messages.
2474
2475 rcutree.jiffies_till_first_fqs= [KNL,BOOT]
2476 Set delay from grace-period initialization to
2477 first attempt to force quiescent states.
2478 Units are jiffies, minimum value is zero,
2479 and maximum value is HZ.
2480
2481 rcutree.jiffies_till_next_fqs= [KNL,BOOT]
2482 Set delay between subsequent attempts to force
2483 quiescent states. Units are jiffies, minimum
2484 value is one, and maximum value is HZ.
2485
2486 rcutorture.fqs_duration= [KNL,BOOT]
2487 Set duration of force_quiescent_state bursts.
2488
2489 rcutorture.fqs_holdoff= [KNL,BOOT]
2490 Set holdoff time within force_quiescent_state bursts.
2491
2492 rcutorture.fqs_stutter= [KNL,BOOT]
2493 Set wait time between force_quiescent_state bursts.
2494
2495 rcutorture.irqreader= [KNL,BOOT]
2496 Test RCU readers from irq handlers.
2497
2498 rcutorture.n_barrier_cbs= [KNL,BOOT]
2499 Set callbacks/threads for rcu_barrier() testing.
2500
2501 rcutorture.nfakewriters= [KNL,BOOT]
2502 Set number of concurrent RCU writers. These just
2503 stress RCU, they don't participate in the actual
2504 test, hence the "fake".
2505
2506 rcutorture.nreaders= [KNL,BOOT]
2507 Set number of RCU readers.
2508
2509 rcutorture.onoff_holdoff= [KNL,BOOT]
2510 Set time (s) after boot for CPU-hotplug testing.
2511
2512 rcutorture.onoff_interval= [KNL,BOOT]
2513 Set time (s) between CPU-hotplug operations, or
2514 zero to disable CPU-hotplug testing.
2515
2516 rcutorture.shuffle_interval= [KNL,BOOT]
2517 Set task-shuffle interval (s). Shuffling tasks
2518 allows some CPUs to go into dyntick-idle mode
2519 during the rcutorture test.
2520
2521 rcutorture.shutdown_secs= [KNL,BOOT]
2522 Set time (s) after boot system shutdown. This
2523 is useful for hands-off automated testing.
2524
2525 rcutorture.stall_cpu= [KNL,BOOT]
2526 Duration of CPU stall (s) to test RCU CPU stall
2527 warnings, zero to disable.
2528
2529 rcutorture.stall_cpu_holdoff= [KNL,BOOT]
2530 Time to wait (s) after boot before inducing stall.
2531
2532 rcutorture.stat_interval= [KNL,BOOT]
2533 Time (s) between statistics printk()s.
2534
2535 rcutorture.stutter= [KNL,BOOT]
2536 Time (s) to stutter testing, for example, specifying
2537 five seconds causes the test to run for five seconds,
2538 wait for five seconds, and so on. This tests RCU's
2539 ability to transition abruptly to and from idle.
2540
2541 rcutorture.test_boost= [KNL,BOOT]
2542 Test RCU priority boosting? 0=no, 1=maybe, 2=yes.
2543 "Maybe" means test if the RCU implementation
2544 under test support RCU priority boosting.
2545
2546 rcutorture.test_boost_duration= [KNL,BOOT]
2547 Duration (s) of each individual boost test.
2548
2549 rcutorture.test_boost_interval= [KNL,BOOT]
2550 Interval (s) between each boost test.
2551
2552 rcutorture.test_no_idle_hz= [KNL,BOOT]
2553 Test RCU's dyntick-idle handling. See also the
2554 rcutorture.shuffle_interval parameter.
2555
2556 rcutorture.torture_type= [KNL,BOOT]
2557 Specify the RCU implementation to test.
2558
2559 rcutorture.verbose= [KNL,BOOT]
2560 Enable additional printk() statements.
2561
2562 rdinit= [KNL] 2214 rdinit= [KNL]
2563 Format: <full_path> 2215 Format: <full_path>
2564 Run specified binary instead of /init from the ramdisk, 2216 Run specified binary instead of /init from the ramdisk,
@@ -2589,8 +2241,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
2589 2241
2590 resume= [SWSUSP] 2242 resume= [SWSUSP]
2591 Specify the partition device for software suspend 2243 Specify the partition device for software suspend
2592 Format:
2593 {/dev/<dev> | PARTUUID=<uuid> | <int>:<int> | <hex>}
2594 2244
2595 resume_offset= [SWSUSP] 2245 resume_offset= [SWSUSP]
2596 Specify the offset from the beginning of the partition 2246 Specify the offset from the beginning of the partition
@@ -2598,13 +2248,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
2598 in <PAGE_SIZE> units (needed only for swap files). 2248 in <PAGE_SIZE> units (needed only for swap files).
2599 See Documentation/power/swsusp-and-swap-files.txt 2249 See Documentation/power/swsusp-and-swap-files.txt
2600 2250
2601 resumedelay= [HIBERNATION] Delay (in seconds) to pause before attempting to
2602 read the resume files
2603
2604 resumewait [HIBERNATION] Wait (indefinitely) for resume device to show up.
2605 Useful for devices that are detected asynchronously
2606 (e.g. USB and MMC devices).
2607
2608 hibernate= [HIBERNATION] 2251 hibernate= [HIBERNATION]
2609 noresume Don't check if there's a hibernation image 2252 noresume Don't check if there's a hibernation image
2610 present during boot. 2253 present during boot.
@@ -2645,15 +2288,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
2645 2288
2646 sched_debug [KNL] Enables verbose scheduler debug messages. 2289 sched_debug [KNL] Enables verbose scheduler debug messages.
2647 2290
2648 skew_tick= [KNL] Offset the periodic timer tick per cpu to mitigate
2649 xtime_lock contention on larger systems, and/or RCU lock
2650 contention on all systems with CONFIG_MAXSMP set.
2651 Format: { "0" | "1" }
2652 0 -- disable. (may be 1 via CONFIG_CMDLINE="skew_tick=1"
2653 1 -- enable.
2654 Note: increases power consumption, thus should only be
2655 enabled if running jitter sensitive (HPC/RT) workloads.
2656
2657 security= [SECURITY] Choose a security module to enable at boot. 2291 security= [SECURITY] Choose a security module to enable at boot.
2658 If this boot parameter is not specified, only the first 2292 If this boot parameter is not specified, only the first
2659 security module asking for security registration will be 2293 security module asking for security registration will be
@@ -2692,12 +2326,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
2692 2326
2693 slram= [HW,MTD] 2327 slram= [HW,MTD]
2694 2328
2695 slab_max_order= [MM, SLAB]
2696 Determines the maximum allowed order for slabs.
2697 A high setting may cause OOMs due to memory
2698 fragmentation. Defaults to 1 for systems with
2699 more than 32MB of RAM, 0 otherwise.
2700
2701 slub_debug[=options[,slabs]] [MM, SLUB] 2329 slub_debug[=options[,slabs]] [MM, SLUB]
2702 Enabling slub_debug allows one to determine the 2330 Enabling slub_debug allows one to determine the
2703 culprit if slab objects become corrupted. Enabling 2331 culprit if slab objects become corrupted. Enabling
@@ -2722,7 +2350,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
2722 For more information see Documentation/vm/slub.txt. 2350 For more information see Documentation/vm/slub.txt.
2723 2351
2724 slub_min_order= [MM, SLUB] 2352 slub_min_order= [MM, SLUB]
2725 Determines the minimum page order for slabs. Must be 2353 Determines the mininum page order for slabs. Must be
2726 lower than slub_max_order. 2354 lower than slub_max_order.
2727 For more information see Documentation/vm/slub.txt. 2355 For more information see Documentation/vm/slub.txt.
2728 2356
@@ -2736,6 +2364,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
2736 smart2= [HW] 2364 smart2= [HW]
2737 Format: <io1>[,<io2>[,...,<io8>]] 2365 Format: <io1>[,<io2>[,...,<io8>]]
2738 2366
2367 smp-alt-once [X86-32,SMP] On a hotplug CPU system, only
2368 attempt to substitute SMP alternatives once at boot.
2369
2739 smsc-ircc2.nopnp [HW] Don't use PNP to discover SMC devices 2370 smsc-ircc2.nopnp [HW] Don't use PNP to discover SMC devices
2740 smsc-ircc2.ircc_cfg= [HW] Device configuration I/O port 2371 smsc-ircc2.ircc_cfg= [HW] Device configuration I/O port
2741 smsc-ircc2.ircc_sir= [HW] SIR base I/O port 2372 smsc-ircc2.ircc_sir= [HW] SIR base I/O port
@@ -2752,7 +2383,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
2752 Format: <integer> 2383 Format: <integer>
2753 2384
2754 sonypi.*= [HW] Sony Programmable I/O Control Device driver 2385 sonypi.*= [HW] Sony Programmable I/O Control Device driver
2755 See Documentation/laptops/sonypi.txt 2386 See Documentation/sonypi.txt
2756 2387
2757 specialix= [HW,SERIAL] Specialix multi-serial port adapter 2388 specialix= [HW,SERIAL] Specialix multi-serial port adapter
2758 See Documentation/serial/specialix.txt. 2389 See Documentation/serial/specialix.txt.
@@ -2765,14 +2396,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
2765 stacktrace [FTRACE] 2396 stacktrace [FTRACE]
2766 Enabled the stack tracer on boot up. 2397 Enabled the stack tracer on boot up.
2767 2398
2768 stacktrace_filter=[function-list]
2769 [FTRACE] Limit the functions that the stack tracer
2770 will trace at boot up. function-list is a comma separated
2771 list of functions. This list can be changed at run
2772 time by the stack_trace_filter file in the debugfs
2773 tracing directory. Note, this enables stack tracing
2774 and the stacktrace above is not needed.
2775
2776 sti= [PARISC,HW] 2399 sti= [PARISC,HW]
2777 Format: <num> 2400 Format: <num>
2778 Set the STI (builtin display/keyboard on the HP-PARISC 2401 Set the STI (builtin display/keyboard on the HP-PARISC
@@ -2885,7 +2508,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
2885 2508
2886 threadirqs [KNL] 2509 threadirqs [KNL]
2887 Force threading of all interrupt handlers except those 2510 Force threading of all interrupt handlers except those
2888 marked explicitly IRQF_NO_THREAD. 2511 marked explicitely IRQF_NO_THREAD.
2889 2512
2890 topology= [S390] 2513 topology= [S390]
2891 Format: {off | on} 2514 Format: {off | on}
@@ -2914,29 +2537,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
2914 to facilitate early boot debugging. 2537 to facilitate early boot debugging.
2915 See also Documentation/trace/events.txt 2538 See also Documentation/trace/events.txt
2916 2539
2917 trace_options=[option-list]
2918 [FTRACE] Enable or disable tracer options at boot.
2919 The option-list is a comma delimited list of options
2920 that can be enabled or disabled just as if you were
2921 to echo the option name into
2922
2923 /sys/kernel/debug/tracing/trace_options
2924
2925 For example, to enable stacktrace option (to dump the
2926 stack trace of each event), add to the command line:
2927
2928 trace_options=stacktrace
2929
2930 See also Documentation/trace/ftrace.txt "trace options"
2931 section.
2932
2933 transparent_hugepage=
2934 [KNL]
2935 Format: [always|madvise|never]
2936 Can be used to control the default behavior of the system
2937 with respect to transparent hugepages.
2938 See Documentation/vm/transhuge.txt for more details.
2939
2940 tsc= Disable clocksource stability checks for TSC. 2540 tsc= Disable clocksource stability checks for TSC.
2941 Format: <string> 2541 Format: <string>
2942 [x86] reliable: mark tsc clocksource as reliable, this 2542 [x86] reliable: mark tsc clocksource as reliable, this
@@ -2996,10 +2596,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
2996 [USB] Start with the old device initialization 2596 [USB] Start with the old device initialization
2997 scheme (default 0 = off). 2597 scheme (default 0 = off).
2998 2598
2999 usbcore.usbfs_memory_mb=
3000 [USB] Memory limit (in MB) for buffers allocated by
3001 usbfs (default = 16, 0 = max = 2047).
3002
3003 usbcore.use_both_schemes= 2599 usbcore.use_both_schemes=
3004 [USB] Try the other device initialization scheme 2600 [USB] Try the other device initialization scheme
3005 if the first one fails (default 1 = enabled). 2601 if the first one fails (default 1 = enabled).
@@ -3047,8 +2643,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
3047 initial READ(10) command); 2643 initial READ(10) command);
3048 o = CAPACITY_OK (accept the capacity 2644 o = CAPACITY_OK (accept the capacity
3049 reported by the device); 2645 reported by the device);
3050 p = WRITE_CACHE (the device cache is ON
3051 by default);
3052 r = IGNORE_RESIDUE (the device reports 2646 r = IGNORE_RESIDUE (the device reports
3053 bogus residue values); 2647 bogus residue values);
3054 s = SINGLE_LUN (the device has only one 2648 s = SINGLE_LUN (the device has only one
@@ -3090,22 +2684,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
3090 video= [FB] Frame buffer configuration 2684 video= [FB] Frame buffer configuration
3091 See Documentation/fb/modedb.txt. 2685 See Documentation/fb/modedb.txt.
3092 2686
3093 virtio_mmio.device=
3094 [VMMIO] Memory mapped virtio (platform) device.
3095
3096 <size>@<baseaddr>:<irq>[:<id>]
3097 where:
3098 <size> := size (can use standard suffixes
3099 like K, M and G)
3100 <baseaddr> := physical base address
3101 <irq> := interrupt number (as passed to
3102 request_irq())
3103 <id> := (optional) platform device id
3104 example:
3105 virtio_mmio.device=1K@0x100b0000:48:7
3106
3107 Can be used multiple times for multiple devices.
3108
3109 vga= [BOOT,X86-32] Select a particular video mode 2687 vga= [BOOT,X86-32] Select a particular video mode
3110 See Documentation/x86/boot.txt and 2688 See Documentation/x86/boot.txt and
3111 Documentation/svga.txt. 2689 Documentation/svga.txt.
@@ -3136,10 +2714,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
3136 functions are at fixed addresses, they make nice 2714 functions are at fixed addresses, they make nice
3137 targets for exploits that can control RIP. 2715 targets for exploits that can control RIP.
3138 2716
3139 emulate [default] Vsyscalls turn into traps and are 2717 emulate Vsyscalls turn into traps and are emulated
3140 emulated reasonably safely. 2718 reasonably safely.
3141 2719
3142 native Vsyscalls are native syscall instructions. 2720 native [default] Vsyscalls are native syscall
2721 instructions.
3143 This is a little bit faster than trapping 2722 This is a little bit faster than trapping
3144 and makes a few dynamic recompilers work 2723 and makes a few dynamic recompilers work
3145 better than they would in emulation mode. 2724 better than they would in emulation mode.