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-rw-r--r--Documentation/kernel-parameters.txt133
1 files changed, 115 insertions, 18 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index e07c432c731f..e7bea3e85304 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -87,7 +87,8 @@ parameter is applicable:
87 SH SuperH architecture is enabled. 87 SH SuperH architecture is enabled.
88 SMP The kernel is an SMP kernel. 88 SMP The kernel is an SMP kernel.
89 SPARC Sparc architecture is enabled. 89 SPARC Sparc architecture is enabled.
90 SWSUSP Software suspend is enabled. 90 SWSUSP Software suspend (hibernation) is enabled.
91 SUSPEND System suspend states are enabled.
91 TS Appropriate touchscreen support is enabled. 92 TS Appropriate touchscreen support is enabled.
92 USB USB support is enabled. 93 USB USB support is enabled.
93 USBHID USB Human Interface Device support is enabled. 94 USBHID USB Human Interface Device support is enabled.
@@ -147,10 +148,16 @@ and is between 256 and 4096 characters. It is defined in the file
147 default: 0 148 default: 0
148 149
149 acpi_sleep= [HW,ACPI] Sleep options 150 acpi_sleep= [HW,ACPI] Sleep options
150 Format: { s3_bios, s3_mode, s3_beep } 151 Format: { s3_bios, s3_mode, s3_beep, s4_nohwsig, old_ordering }
151 See Documentation/power/video.txt for s3_bios and s3_mode. 152 See Documentation/power/video.txt for s3_bios and s3_mode.
152 s3_beep is for debugging; it makes the PC's speaker beep 153 s3_beep is for debugging; it makes the PC's speaker beep
153 as soon as the kernel's real-mode entry point is called. 154 as soon as the kernel's real-mode entry point is called.
155 s4_nohwsig prevents ACPI hardware signature from being
156 used during resume from hibernation.
157 old_ordering causes the ACPI 1.0 ordering of the _PTS
158 control method, wrt putting devices into low power
159 states, to be enforced (the ACPI 2.0 ordering of _PTS is
160 used by default).
154 161
155 acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode 162 acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
156 Format: { level | edge | high | low } 163 Format: { level | edge | high | low }
@@ -271,6 +278,17 @@ and is between 256 and 4096 characters. It is defined in the file
271 aic79xx= [HW,SCSI] 278 aic79xx= [HW,SCSI]
272 See Documentation/scsi/aic79xx.txt. 279 See Documentation/scsi/aic79xx.txt.
273 280
281 amd_iommu= [HW,X86-84]
282 Pass parameters to the AMD IOMMU driver in the system.
283 Possible values are:
284 isolate - enable device isolation (each device, as far
285 as possible, will get its own protection
286 domain)
287 amd_iommu_size= [HW,X86-64]
288 Define the size of the aperture for the AMD IOMMU
289 driver. Possible values are:
290 '32M', '64M' (default), '128M', '256M', '512M', '1G'
291
274 amijoy.map= [HW,JOY] Amiga joystick support 292 amijoy.map= [HW,JOY] Amiga joystick support
275 Map of devices attached to JOY0DAT and JOY1DAT 293 Map of devices attached to JOY0DAT and JOY1DAT
276 Format: <a>,<b> 294 Format: <a>,<b>
@@ -295,7 +313,7 @@ and is between 256 and 4096 characters. It is defined in the file
295 when initialising the APIC and IO-APIC components. 313 when initialising the APIC and IO-APIC components.
296 314
297 apm= [APM] Advanced Power Management 315 apm= [APM] Advanced Power Management
298 See header of arch/i386/kernel/apm.c. 316 See header of arch/x86/kernel/apm_32.c.
299 317
300 arcrimi= [HW,NET] ARCnet - "RIM I" (entirely mem-mapped) cards 318 arcrimi= [HW,NET] ARCnet - "RIM I" (entirely mem-mapped) cards
301 Format: <io>,<irq>,<nodeID> 319 Format: <io>,<irq>,<nodeID>
@@ -560,6 +578,8 @@ and is between 256 and 4096 characters. It is defined in the file
560 578
561 debug_objects [KNL] Enable object debugging 579 debug_objects [KNL] Enable object debugging
562 580
581 debugpat [X86] Enable PAT debugging
582
563 decnet.addr= [HW,NET] 583 decnet.addr= [HW,NET]
564 Format: <area>[,<node>] 584 Format: <area>[,<node>]
565 See also Documentation/networking/decnet.txt. 585 See also Documentation/networking/decnet.txt.
@@ -599,6 +619,29 @@ and is between 256 and 4096 characters. It is defined in the file
599 See drivers/char/README.epca and 619 See drivers/char/README.epca and
600 Documentation/digiepca.txt. 620 Documentation/digiepca.txt.
601 621
622 disable_mtrr_cleanup [X86]
623 enable_mtrr_cleanup [X86]
624 The kernel tries to adjust MTRR layout from continuous
625 to discrete, to make X server driver able to add WB
626 entry later. This parameter enables/disables that.
627
628 mtrr_chunk_size=nn[KMG] [X86]
629 used for mtrr cleanup. It is largest continous chunk
630 that could hold holes aka. UC entries.
631
632 mtrr_gran_size=nn[KMG] [X86]
633 Used for mtrr cleanup. It is granularity of mtrr block.
634 Default is 1.
635 Large value could prevent small alignment from
636 using up MTRRs.
637
638 mtrr_spare_reg_nr=n [X86]
639 Format: <integer>
640 Range: 0,7 : spare reg number
641 Default : 1
642 Used for mtrr cleanup. It is spare mtrr entries number.
643 Set to 2 or more if your graphical card needs more.
644
602 disable_mtrr_trim [X86, Intel and AMD only] 645 disable_mtrr_trim [X86, Intel and AMD only]
603 By default the kernel will trim any uncacheable 646 By default the kernel will trim any uncacheable
604 memory out of your available memory pool based on 647 memory out of your available memory pool based on
@@ -638,7 +681,7 @@ and is between 256 and 4096 characters. It is defined in the file
638 681
639 elanfreq= [X86-32] 682 elanfreq= [X86-32]
640 See comment before function elanfreq_setup() in 683 See comment before function elanfreq_setup() in
641 arch/i386/kernel/cpu/cpufreq/elanfreq.c. 684 arch/x86/kernel/cpu/cpufreq/elanfreq.c.
642 685
643 elevator= [IOSCHED] 686 elevator= [IOSCHED]
644 Format: {"anticipatory" | "cfq" | "deadline" | "noop"} 687 Format: {"anticipatory" | "cfq" | "deadline" | "noop"}
@@ -722,9 +765,6 @@ and is between 256 and 4096 characters. It is defined in the file
722 hd= [EIDE] (E)IDE hard drive subsystem geometry 765 hd= [EIDE] (E)IDE hard drive subsystem geometry
723 Format: <cyl>,<head>,<sect> 766 Format: <cyl>,<head>,<sect>
724 767
725 hd?= [HW] (E)IDE subsystem
726 hd?lun= See Documentation/ide/ide.txt.
727
728 highmem=nn[KMG] [KNL,BOOT] forces the highmem zone to have an exact 768 highmem=nn[KMG] [KNL,BOOT] forces the highmem zone to have an exact
729 size of <nn>. This works even on boxes that have no 769 size of <nn>. This works even on boxes that have no
730 highmem otherwise. This also works to reduce highmem 770 highmem otherwise. This also works to reduce highmem
@@ -737,8 +777,22 @@ and is between 256 and 4096 characters. It is defined in the file
737 hisax= [HW,ISDN] 777 hisax= [HW,ISDN]
738 See Documentation/isdn/README.HiSax. 778 See Documentation/isdn/README.HiSax.
739 779
740 hugepages= [HW,X86-32,IA-64] Maximal number of HugeTLB pages. 780 hugepages= [HW,X86-32,IA-64] HugeTLB pages to allocate at boot.
741 hugepagesz= [HW,IA-64,PPC] The size of the HugeTLB pages. 781 hugepagesz= [HW,IA-64,PPC,X86-64] The size of the HugeTLB pages.
782 On x86-64 and powerpc, this option can be specified
783 multiple times interleaved with hugepages= to reserve
784 huge pages of different sizes. Valid pages sizes on
785 x86-64 are 2M (when the CPU supports "pse") and 1G
786 (when the CPU supports the "pdpe1gb" cpuinfo flag)
787 Note that 1GB pages can only be allocated at boot time
788 using hugepages= and not freed afterwards.
789 default_hugepagesz=
790 [same as hugepagesz=] The size of the default
791 HugeTLB page size. This is the size represented by
792 the legacy /proc/ hugepages APIs, used for SHM, and
793 default size when mounting hugetlbfs filesystems.
794 Defaults to the default architecture's huge page size
795 if not specified.
742 796
743 i8042.direct [HW] Put keyboard port into non-translated mode 797 i8042.direct [HW] Put keyboard port into non-translated mode
744 i8042.dumbkbd [HW] Pretend that controller can only read data from 798 i8042.dumbkbd [HW] Pretend that controller can only read data from
@@ -785,7 +839,7 @@ and is between 256 and 4096 characters. It is defined in the file
785 See Documentation/ide/ide.txt. 839 See Documentation/ide/ide.txt.
786 840
787 idle= [X86] 841 idle= [X86]
788 Format: idle=poll or idle=mwait 842 Format: idle=poll or idle=mwait, idle=halt, idle=nomwait
789 Poll forces a polling idle loop that can slightly improves the performance 843 Poll forces a polling idle loop that can slightly improves the performance
790 of waking up a idle CPU, but will use a lot of power and make the system 844 of waking up a idle CPU, but will use a lot of power and make the system
791 run hot. Not recommended. 845 run hot. Not recommended.
@@ -793,6 +847,9 @@ and is between 256 and 4096 characters. It is defined in the file
793 to not use it because it doesn't save as much power as a normal idle 847 to not use it because it doesn't save as much power as a normal idle
794 loop use the MONITOR/MWAIT idle loop anyways. Performance should be the same 848 loop use the MONITOR/MWAIT idle loop anyways. Performance should be the same
795 as idle=poll. 849 as idle=poll.
850 idle=halt. Halt is forced to be used for CPU idle.
851 In such case C2/C3 won't be used again.
852 idle=nomwait. Disable mwait for CPU C-states
796 853
797 ide-pci-generic.all-generic-ide [HW] (E)IDE subsystem 854 ide-pci-generic.all-generic-ide [HW] (E)IDE subsystem
798 Claim all unknown PCI IDE storage controllers. 855 Claim all unknown PCI IDE storage controllers.
@@ -1166,7 +1223,7 @@ and is between 256 and 4096 characters. It is defined in the file
1166 or 1223 or
1167 memmap=0x10000$0x18690000 1224 memmap=0x10000$0x18690000
1168 1225
1169 memtest= [KNL,X86_64] Enable memtest 1226 memtest= [KNL,X86] Enable memtest
1170 Format: <integer> 1227 Format: <integer>
1171 range: 0,4 : pattern number 1228 range: 0,4 : pattern number
1172 default : 0 <disable> 1229 default : 0 <disable>
@@ -1185,6 +1242,14 @@ and is between 256 and 4096 characters. It is defined in the file
1185 1242
1186 mga= [HW,DRM] 1243 mga= [HW,DRM]
1187 1244
1245 mminit_loglevel=
1246 [KNL] When CONFIG_DEBUG_MEMORY_INIT is set, this
1247 parameter allows control of the logging verbosity for
1248 the additional memory initialisation checks. A value
1249 of 0 disables mminit logging and a level of 4 will
1250 log everything. Information is printed at KERN_DEBUG
1251 so loglevel=8 may also need to be specified.
1252
1188 mousedev.tap_time= 1253 mousedev.tap_time=
1189 [MOUSE] Maximum time between finger touching and 1254 [MOUSE] Maximum time between finger touching and
1190 leaving touchpad surface for touch to be considered 1255 leaving touchpad surface for touch to be considered
@@ -1208,6 +1273,11 @@ and is between 256 and 4096 characters. It is defined in the file
1208 mtdparts= [MTD] 1273 mtdparts= [MTD]
1209 See drivers/mtd/cmdlinepart.c. 1274 See drivers/mtd/cmdlinepart.c.
1210 1275
1276 mtdset= [ARM]
1277 ARM/S3C2412 JIVE boot control
1278
1279 See arch/arm/mach-s3c2412/mach-jive.c
1280
1211 mtouchusb.raw_coordinates= 1281 mtouchusb.raw_coordinates=
1212 [HW] Make the MicroTouch USB driver use raw coordinates 1282 [HW] Make the MicroTouch USB driver use raw coordinates
1213 ('y', default) or cooked coordinates ('n') 1283 ('y', default) or cooked coordinates ('n')
@@ -1234,6 +1304,13 @@ and is between 256 and 4096 characters. It is defined in the file
1234 This usage is only documented in each driver source 1304 This usage is only documented in each driver source
1235 file if at all. 1305 file if at all.
1236 1306
1307 nf_conntrack.acct=
1308 [NETFILTER] Enable connection tracking flow accounting
1309 0 to disable accounting
1310 1 to enable accounting
1311 Default value depends on CONFIG_NF_CT_ACCT that is
1312 going to be removed in 2.6.29.
1313
1237 nfsaddrs= [NFS] 1314 nfsaddrs= [NFS]
1238 See Documentation/filesystems/nfsroot.txt. 1315 See Documentation/filesystems/nfsroot.txt.
1239 1316
@@ -1496,6 +1573,9 @@ and is between 256 and 4096 characters. It is defined in the file
1496 Use with caution as certain devices share 1573 Use with caution as certain devices share
1497 address decoders between ROMs and other 1574 address decoders between ROMs and other
1498 resources. 1575 resources.
1576 norom [X86-32,X86_64] Do not assign address space to
1577 expansion ROMs that do not already have
1578 BIOS assigned address ranges.
1499 irqmask=0xMMMM [X86-32] Set a bit mask of IRQs allowed to be 1579 irqmask=0xMMMM [X86-32] Set a bit mask of IRQs allowed to be
1500 assigned automatically to PCI devices. You can 1580 assigned automatically to PCI devices. You can
1501 make the kernel exclude IRQs of your ISA cards 1581 make the kernel exclude IRQs of your ISA cards
@@ -1571,6 +1651,10 @@ and is between 256 and 4096 characters. It is defined in the file
1571 Format: { parport<nr> | timid | 0 } 1651 Format: { parport<nr> | timid | 0 }
1572 See also Documentation/parport.txt. 1652 See also Documentation/parport.txt.
1573 1653
1654 pmtmr= [X86] Manual setup of pmtmr I/O Port.
1655 Override pmtimer IOPort with a hex value.
1656 e.g. pmtmr=0x508
1657
1574 pnpacpi= [ACPI] 1658 pnpacpi= [ACPI]
1575 { off } 1659 { off }
1576 1660
@@ -1679,6 +1763,10 @@ and is between 256 and 4096 characters. It is defined in the file
1679 Format: <reboot_mode>[,<reboot_mode2>[,...]] 1763 Format: <reboot_mode>[,<reboot_mode2>[,...]]
1680 See arch/*/kernel/reboot.c or arch/*/kernel/process.c 1764 See arch/*/kernel/reboot.c or arch/*/kernel/process.c
1681 1765
1766 relax_domain_level=
1767 [KNL, SMP] Set scheduler's default relax_domain_level.
1768 See Documentation/cpusets.txt.
1769
1682 reserve= [KNL,BUGS] Force the kernel to ignore some iomem area 1770 reserve= [KNL,BUGS] Force the kernel to ignore some iomem area
1683 1771
1684 reservetop= [X86-32] 1772 reservetop= [X86-32]
@@ -1971,6 +2059,9 @@ and is between 256 and 4096 characters. It is defined in the file
1971 2059
1972 snd-ymfpci= [HW,ALSA] 2060 snd-ymfpci= [HW,ALSA]
1973 2061
2062 softlockup_panic=
2063 [KNL] Should the soft-lockup detector generate panics.
2064
1974 sonypi.*= [HW] Sony Programmable I/O Control Device driver 2065 sonypi.*= [HW] Sony Programmable I/O Control Device driver
1975 See Documentation/sonypi.txt 2066 See Documentation/sonypi.txt
1976 2067
@@ -2035,6 +2126,12 @@ and is between 256 and 4096 characters. It is defined in the file
2035 2126
2036 tdfx= [HW,DRM] 2127 tdfx= [HW,DRM]
2037 2128
2129 test_suspend= [SUSPEND]
2130 Specify "mem" (for Suspend-to-RAM) or "standby" (for
2131 standby suspend) as the system sleep state to briefly
2132 enter during system startup. The system is woken from
2133 this state using a wakeup-capable RTC alarm.
2134
2038 thash_entries= [KNL,NET] 2135 thash_entries= [KNL,NET]
2039 Set number of hash buckets for TCP connection 2136 Set number of hash buckets for TCP connection
2040 2137
@@ -2062,13 +2159,6 @@ and is between 256 and 4096 characters. It is defined in the file
2062 <deci-seconds>: poll all this frequency 2159 <deci-seconds>: poll all this frequency
2063 0: no polling (default) 2160 0: no polling (default)
2064 2161
2065 tipar.timeout= [HW,PPT]
2066 Set communications timeout in tenths of a second
2067 (default 15).
2068
2069 tipar.delay= [HW,PPT]
2070 Set inter-bit delay in microseconds (default 10).
2071
2072 tmscsim= [HW,SCSI] 2162 tmscsim= [HW,SCSI]
2073 See comment before function dc390_setup() in 2163 See comment before function dc390_setup() in
2074 drivers/scsi/tmscsim.c. 2164 drivers/scsi/tmscsim.c.
@@ -2102,6 +2192,10 @@ and is between 256 and 4096 characters. It is defined in the file
2102 Note that genuine overcurrent events won't be 2192 Note that genuine overcurrent events won't be
2103 reported either. 2193 reported either.
2104 2194
2195 unknown_nmi_panic
2196 [X86-32,X86-64]
2197 Set unknown_nmi_panic=1 early on boot.
2198
2105 usbcore.autosuspend= 2199 usbcore.autosuspend=
2106 [USB] The autosuspend time delay (in seconds) used 2200 [USB] The autosuspend time delay (in seconds) used
2107 for newly-detected USB devices (default 2). This 2201 for newly-detected USB devices (default 2). This
@@ -2112,6 +2206,9 @@ and is between 256 and 4096 characters. It is defined in the file
2112 usbhid.mousepoll= 2206 usbhid.mousepoll=
2113 [USBHID] The interval which mice are to be polled at. 2207 [USBHID] The interval which mice are to be polled at.
2114 2208
2209 add_efi_memmap [EFI; x86-32,X86-64] Include EFI memory map in
2210 kernel's map of available physical RAM.
2211
2115 vdso= [X86-32,SH,x86-64] 2212 vdso= [X86-32,SH,x86-64]
2116 vdso=2: enable compat VDSO (default with COMPAT_VDSO) 2213 vdso=2: enable compat VDSO (default with COMPAT_VDSO)
2117 vdso=1: enable VDSO (default) 2214 vdso=1: enable VDSO (default)