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-rw-r--r--Documentation/kernel-parameters.txt629
1 files changed, 357 insertions, 272 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 54f21a5c262b..e87bdbfbcc75 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
20Hyphens (dashes) and underscores are equivalent in parameter names, so
21 log_buf_len=1M print-fatal-signals=1
22can also be entered as
23 log-buf-len=1M print_fatal_signals=1
24
25
20This document may not be entirely up to date and comprehensive. The command 26This 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
22module. Loadable modules, after being loaded into the running kernel, also 28module. Loadable modules, after being loaded into the running kernel, also
@@ -44,11 +50,13 @@ parameter is applicable:
44 FB The frame buffer device is enabled. 50 FB The frame buffer device is enabled.
45 HW Appropriate hardware is enabled. 51 HW Appropriate hardware is enabled.
46 IA-64 IA-64 architecture is enabled. 52 IA-64 IA-64 architecture is enabled.
53 IMA Integrity measurement architecture is enabled.
47 IOSCHED More than one I/O scheduler is enabled. 54 IOSCHED More than one I/O scheduler is enabled.
48 IP_PNP IP DHCP, BOOTP, or RARP is enabled. 55 IP_PNP IP DHCP, BOOTP, or RARP is enabled.
49 ISAPNP ISA PnP code is enabled. 56 ISAPNP ISA PnP code is enabled.
50 ISDN Appropriate ISDN support is enabled. 57 ISDN Appropriate ISDN support is enabled.
51 JOY Appropriate joystick support is enabled. 58 JOY Appropriate joystick support is enabled.
59 KMEMTRACE kmemtrace is enabled.
52 LIBATA Libata driver is enabled 60 LIBATA Libata driver is enabled
53 LP Printer support is enabled. 61 LP Printer support is enabled.
54 LOOP Loopback device support is enabled. 62 LOOP Loopback device support is enabled.
@@ -132,7 +140,7 @@ and is between 256 and 4096 characters. It is defined in the file
132./include/asm/setup.h as COMMAND_LINE_SIZE. 140./include/asm/setup.h as COMMAND_LINE_SIZE.
133 141
134 142
135 acpi= [HW,ACPI,X86-64,i386] 143 acpi= [HW,ACPI,X86]
136 Advanced Configuration and Power Interface 144 Advanced Configuration and Power Interface
137 Format: { force | off | ht | strict | noirq | rsdt } 145 Format: { force | off | ht | strict | noirq | rsdt }
138 force -- enable ACPI if default was off 146 force -- enable ACPI if default was off
@@ -151,60 +159,6 @@ and is between 256 and 4096 characters. It is defined in the file
151 1,0: use 1st APIC table 159 1,0: use 1st APIC table
152 default: 0 160 default: 0
153 161
154 acpi_sleep= [HW,ACPI] Sleep options
155 Format: { s3_bios, s3_mode, s3_beep, s4_nohwsig,
156 old_ordering, s4_nonvs }
157 See Documentation/power/video.txt for information on
158 s3_bios and s3_mode.
159 s3_beep is for debugging; it makes the PC's speaker beep
160 as soon as the kernel's real-mode entry point is called.
161 s4_nohwsig prevents ACPI hardware signature from being
162 used during resume from hibernation.
163 old_ordering causes the ACPI 1.0 ordering of the _PTS
164 control method, with respect to putting devices into
165 low power states, to be enforced (the ACPI 2.0 ordering
166 of _PTS is used by default).
167 s4_nonvs prevents the kernel from saving/restoring the
168 ACPI NVS memory during hibernation.
169
170 acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
171 Format: { level | edge | high | low }
172
173 acpi_irq_balance [HW,ACPI]
174 ACPI will balance active IRQs
175 default in APIC mode
176
177 acpi_irq_nobalance [HW,ACPI]
178 ACPI will not move active IRQs (default)
179 default in PIC mode
180
181 acpi_irq_pci= [HW,ACPI] If irq_balance, clear listed IRQs for
182 use by PCI
183 Format: <irq>,<irq>...
184
185 acpi_irq_isa= [HW,ACPI] If irq_balance, mark listed IRQs used by ISA
186 Format: <irq>,<irq>...
187
188 acpi_no_auto_ssdt [HW,ACPI] Disable automatic loading of SSDT
189
190 acpi_os_name= [HW,ACPI] Tell ACPI BIOS the name of the OS
191 Format: To spoof as Windows 98: ="Microsoft Windows"
192
193 acpi_osi= [HW,ACPI] Modify list of supported OS interface strings
194 acpi_osi="string1" # add string1 -- only one string
195 acpi_osi="!string2" # remove built-in string2
196 acpi_osi= # disable all strings
197
198 acpi_serialize [HW,ACPI] force serialization of AML methods
199
200 acpi_skip_timer_override [HW,ACPI]
201 Recognize and ignore IRQ0/pin2 Interrupt Override.
202 For broken nForce2 BIOS resulting in XT-PIC timer.
203 acpi_use_timer_override [HW,ACPI]
204 Use timer override. For some broken Nvidia NF5 boards
205 that require a timer override, but don't have
206 HPET
207
208 acpi_backlight= [HW,ACPI] 162 acpi_backlight= [HW,ACPI]
209 acpi_backlight=vendor 163 acpi_backlight=vendor
210 acpi_backlight=video 164 acpi_backlight=video
@@ -212,11 +166,6 @@ and is between 256 and 4096 characters. It is defined in the file
212 (e.g. thinkpad_acpi, sony_acpi, etc.) instead 166 (e.g. thinkpad_acpi, sony_acpi, etc.) instead
213 of the ACPI video.ko driver. 167 of the ACPI video.ko driver.
214 168
215 acpi_display_output= [HW,ACPI]
216 acpi_display_output=vendor
217 acpi_display_output=video
218 See above.
219
220 acpi.debug_layer= [HW,ACPI,ACPI_DEBUG] 169 acpi.debug_layer= [HW,ACPI,ACPI_DEBUG]
221 acpi.debug_level= [HW,ACPI,ACPI_DEBUG] 170 acpi.debug_level= [HW,ACPI,ACPI_DEBUG]
222 Format: <int> 171 Format: <int>
@@ -245,6 +194,41 @@ and is between 256 and 4096 characters. It is defined in the file
245 unusable. The "log_buf_len" parameter may be useful 194 unusable. The "log_buf_len" parameter may be useful
246 if you need to capture more output. 195 if you need to capture more output.
247 196
197 acpi_display_output= [HW,ACPI]
198 acpi_display_output=vendor
199 acpi_display_output=video
200 See above.
201
202 acpi_irq_balance [HW,ACPI]
203 ACPI will balance active IRQs
204 default in APIC mode
205
206 acpi_irq_nobalance [HW,ACPI]
207 ACPI will not move active IRQs (default)
208 default in PIC mode
209
210 acpi_irq_isa= [HW,ACPI] If irq_balance, mark listed IRQs used by ISA
211 Format: <irq>,<irq>...
212
213 acpi_irq_pci= [HW,ACPI] If irq_balance, clear listed IRQs for
214 use by PCI
215 Format: <irq>,<irq>...
216
217 acpi_no_auto_ssdt [HW,ACPI] Disable automatic loading of SSDT
218
219 acpi_os_name= [HW,ACPI] Tell ACPI BIOS the name of the OS
220 Format: To spoof as Windows 98: ="Microsoft Windows"
221
222 acpi_osi= [HW,ACPI] Modify list of supported OS interface strings
223 acpi_osi="string1" # add string1 -- only one string
224 acpi_osi="!string2" # remove built-in string2
225 acpi_osi= # disable all strings
226
227 acpi_pm_good [X86]
228 Override the pmtimer bug detection: force the kernel
229 to assume that this machine's pmtimer latches its value
230 and always returns good values.
231
248 acpi.power_nocheck= [HW,ACPI] 232 acpi.power_nocheck= [HW,ACPI]
249 Format: 1/0 enable/disable the check of power state. 233 Format: 1/0 enable/disable the check of power state.
250 On some bogus BIOS the _PSC object/_STA object of 234 On some bogus BIOS the _PSC object/_STA object of
@@ -253,30 +237,57 @@ and is between 256 and 4096 characters. It is defined in the file
253 power state again in power transition. 237 power state again in power transition.
254 1 : disable the power state check 238 1 : disable the power state check
255 239
256 acpi_pm_good [X86-32,X86-64] 240 acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
257 Override the pmtimer bug detection: force the kernel 241 Format: { level | edge | high | low }
258 to assume that this machine's pmtimer latches its value
259 and always returns good values.
260 242
261 agp= [AGP] 243 acpi_serialize [HW,ACPI] force serialization of AML methods
262 { off | try_unsupported }
263 off: disable AGP support
264 try_unsupported: try to drive unsupported chipsets
265 (may crash computer or cause data corruption)
266 244
267 enable_timer_pin_1 [i386,x86-64] 245 acpi_skip_timer_override [HW,ACPI]
268 Enable PIN 1 of APIC timer 246 Recognize and ignore IRQ0/pin2 Interrupt Override.
269 Can be useful to work around chipset bugs 247 For broken nForce2 BIOS resulting in XT-PIC timer.
270 (in particular on some ATI chipsets).
271 The kernel tries to set a reasonable default.
272 248
273 disable_timer_pin_1 [i386,x86-64] 249 acpi_sleep= [HW,ACPI] Sleep options
274 Disable PIN 1 of APIC timer 250 Format: { s3_bios, s3_mode, s3_beep, s4_nohwsig,
275 Can be useful to work around chipset bugs. 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
269 acpi_enforce_resources= [ACPI]
270 { strict | lax | no }
271 Check for resource conflicts between native drivers
272 and ACPI OperationRegions (SystemIO and SystemMemory
273 only). IO ports and memory declared in ACPI might be
274 used by the ACPI subsystem in arbitrary AML code and
275 can interfere with legacy drivers.
276 strict (default): access to resources claimed by ACPI
277 is denied; legacy drivers trying to access reserved
278 resources will fail to bind to device using them.
279 lax: access to resources claimed by ACPI is allowed;
280 legacy drivers trying to access reserved resources
281 will bind successfully but a warning message is logged.
282 no: ACPI OperationRegions are not marked as reserved,
283 no further checks are performed.
276 284
277 ad1848= [HW,OSS] 285 ad1848= [HW,OSS]
278 Format: <io>,<irq>,<dma>,<dma2>,<type> 286 Format: <io>,<irq>,<dma>,<dma2>,<type>
279 287
288 add_efi_memmap [EFI; X86] Include EFI memory map in
289 kernel's map of available physical RAM.
290
280 advansys= [HW,SCSI] 291 advansys= [HW,SCSI]
281 See header of drivers/scsi/advansys.c. 292 See header of drivers/scsi/advansys.c.
282 293
@@ -287,6 +298,12 @@ and is between 256 and 4096 characters. It is defined in the file
287 Format: <io>,<irq>,<dma>,<mss_io>,<mpu_io>,<mpu_irq> 298 Format: <io>,<irq>,<dma>,<mss_io>,<mpu_io>,<mpu_irq>
288 See also header of sound/oss/aedsp16.c. 299 See also header of sound/oss/aedsp16.c.
289 300
301 agp= [AGP]
302 { off | try_unsupported }
303 off: disable AGP support
304 try_unsupported: try to drive unsupported chipsets
305 (may crash computer or cause data corruption)
306
290 aha152x= [HW,SCSI] 307 aha152x= [HW,SCSI]
291 See Documentation/scsi/aha152x.txt. 308 See Documentation/scsi/aha152x.txt.
292 309
@@ -334,7 +351,7 @@ and is between 256 and 4096 characters. It is defined in the file
334 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
335 APC and your system crashes randomly. 352 APC and your system crashes randomly.
336 353
337 apic= [APIC,i386] Advanced Programmable Interrupt Controller 354 apic= [APIC,X86-32] Advanced Programmable Interrupt Controller
338 Change the output verbosity whilst booting 355 Change the output verbosity whilst booting
339 Format: { quiet (default) | verbose | debug } 356 Format: { quiet (default) | verbose | debug }
340 Change the amount of debugging information output 357 Change the amount of debugging information output
@@ -414,12 +431,6 @@ and is between 256 and 4096 characters. It is defined in the file
414 possible to determine what the correct size should be. 431 possible to determine what the correct size should be.
415 This option provides an override for these situations. 432 This option provides an override for these situations.
416 433
417 security= [SECURITY] Choose a security module to enable at boot.
418 If this boot parameter is not specified, only the first
419 security module asking for security registration will be
420 loaded. An invalid security module name will be treated
421 as if no module has been chosen.
422
423 capability.disable= 434 capability.disable=
424 [SECURITY] Disable capabilities. This would normally 435 [SECURITY] Disable capabilities. This would normally
425 be used only if an alternative security model is to be 436 be used only if an alternative security model is to be
@@ -486,17 +497,11 @@ and is between 256 and 4096 characters. It is defined in the file
486 Also note the kernel might malfunction if you disable 497 Also note the kernel might malfunction if you disable
487 some critical bits. 498 some critical bits.
488 499
489 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
490 in an oops report. 501 in an oops report.
491 Range: 0 - 8192 502 Range: 0 - 8192
492 Default: 64 503 Default: 64
493 504
494 hpet= [X86-32,HPET] option to control HPET usage
495 Format: { enable (default) | disable | force }
496 disable: disable HPET and use PIT instead
497 force: allow force enabled of undocumented chips (ICH4,
498 VIA, nVidia)
499
500 com20020= [HW,NET] ARCnet - COM20020 chipset 505 com20020= [HW,NET] ARCnet - COM20020 chipset
501 Format: 506 Format:
502 <io>[,<irq>[,<nodeID>[,<backplane>[,<ckp>[,<timeout>]]]]] 507 <io>[,<irq>[,<nodeID>[,<backplane>[,<ckp>[,<timeout>]]]]]
@@ -540,23 +545,6 @@ and is between 256 and 4096 characters. It is defined in the file
540 console=brl,ttyS0 545 console=brl,ttyS0
541 For now, only VisioBraille is supported. 546 For now, only VisioBraille is supported.
542 547
543 earlycon= [KNL] Output early console device and options.
544 uart[8250],io,<addr>[,options]
545 uart[8250],mmio,<addr>[,options]
546 Start an early, polled-mode console on the 8250/16550
547 UART at the specified I/O port or MMIO address.
548 The options are the same as for ttyS, above.
549
550 no_console_suspend
551 [HW] Never suspend the console
552 Disable suspending of consoles during suspend and
553 hibernate operations. Once disabled, debugging
554 messages can reach various consoles while the rest
555 of the system is being put to sleep (ie, while
556 debugging driver suspend/resume hooks). This may
557 not work reliably with all consoles, but is known
558 to work with serial and VGA consoles.
559
560 coredump_filter= 548 coredump_filter=
561 [KNL] Change the default value for 549 [KNL] Change the default value for
562 /proc/<pid>/coredump_filter. 550 /proc/<pid>/coredump_filter.
@@ -604,36 +592,22 @@ and is between 256 and 4096 characters. It is defined in the file
604 592
605 debug_objects [KNL] Enable object debugging 593 debug_objects [KNL] Enable object debugging
606 594
595 no_debug_objects
596 [KNL] Disable object debugging
597
607 debugpat [X86] Enable PAT debugging 598 debugpat [X86] Enable PAT debugging
608 599
609 decnet.addr= [HW,NET] 600 decnet.addr= [HW,NET]
610 Format: <area>[,<node>] 601 Format: <area>[,<node>]
611 See also Documentation/networking/decnet.txt. 602 See also Documentation/networking/decnet.txt.
612 603
613 vt.default_blu= [VT] 604 default_hugepagesz=
614 Format: <blue0>,<blue1>,<blue2>,...,<blue15> 605 [same as hugepagesz=] The size of the default
615 Change the default blue palette of the console. 606 HugeTLB page size. This is the size represented by
616 This is a 16-member array composed of values 607 the legacy /proc/ hugepages APIs, used for SHM, and
617 ranging from 0-255. 608 default size when mounting hugetlbfs filesystems.
618 609 Defaults to the default architecture's huge page size
619 vt.default_grn= [VT] 610 if not specified.
620 Format: <green0>,<green1>,<green2>,...,<green15>
621 Change the default green palette of the console.
622 This is a 16-member array composed of values
623 ranging from 0-255.
624
625 vt.default_red= [VT]
626 Format: <red0>,<red1>,<red2>,...,<red15>
627 Change the default red palette of the console.
628 This is a 16-member array composed of values
629 ranging from 0-255.
630
631 vt.default_utf8=
632 [VT]
633 Format=<0|1>
634 Set system-wide default UTF-8 mode for all tty's.
635 Default is 1, i.e. UTF-8 mode is enabled for all
636 newly opened terminals.
637 611
638 dhash_entries= [KNL] 612 dhash_entries= [KNL]
639 Set number of hash buckets for dentry cache. 613 Set number of hash buckets for dentry cache.
@@ -646,27 +620,9 @@ and is between 256 and 4096 characters. It is defined in the file
646 Documentation/serial/digiepca.txt. 620 Documentation/serial/digiepca.txt.
647 621
648 disable_mtrr_cleanup [X86] 622 disable_mtrr_cleanup [X86]
649 enable_mtrr_cleanup [X86]
650 The kernel tries to adjust MTRR layout from continuous 623 The kernel tries to adjust MTRR layout from continuous
651 to discrete, to make X server driver able to add WB 624 to discrete, to make X server driver able to add WB
652 entry later. This parameter enables/disables that. 625 entry later. This parameter disables that.
653
654 mtrr_chunk_size=nn[KMG] [X86]
655 used for mtrr cleanup. It is largest continous chunk
656 that could hold holes aka. UC entries.
657
658 mtrr_gran_size=nn[KMG] [X86]
659 Used for mtrr cleanup. It is granularity of mtrr block.
660 Default is 1.
661 Large value could prevent small alignment from
662 using up MTRRs.
663
664 mtrr_spare_reg_nr=n [X86]
665 Format: <integer>
666 Range: 0,7 : spare reg number
667 Default : 1
668 Used for mtrr cleanup. It is spare mtrr entries number.
669 Set to 2 or more if your graphical card needs more.
670 626
671 disable_mtrr_trim [X86, Intel and AMD only] 627 disable_mtrr_trim [X86, Intel and AMD only]
672 By default the kernel will trim any uncacheable 628 By default the kernel will trim any uncacheable
@@ -674,13 +630,39 @@ and is between 256 and 4096 characters. It is defined in the file
674 MTRR settings. This parameter disables that behavior, 630 MTRR settings. This parameter disables that behavior,
675 possibly causing your machine to run very slowly. 631 possibly causing your machine to run very slowly.
676 632
633 disable_timer_pin_1 [X86]
634 Disable PIN 1 of APIC timer
635 Can be useful to work around chipset bugs.
636
677 dmasound= [HW,OSS] Sound subsystem buffers 637 dmasound= [HW,OSS] Sound subsystem buffers
678 638
639 dma_debug=off If the kernel is compiled with DMA_API_DEBUG support,
640 this option disables the debugging code at boot.
641
642 dma_debug_entries=<number>
643 This option allows to tune the number of preallocated
644 entries for DMA-API debugging code. One entry is
645 required per DMA-API allocation. Use this if the
646 DMA-API debugging code disables itself because the
647 architectural default is too low.
648
679 dscc4.setup= [NET] 649 dscc4.setup= [NET]
680 650
681 dtc3181e= [HW,SCSI] 651 dtc3181e= [HW,SCSI]
682 652
683 earlyprintk= [X86-32,X86-64,SH,BLACKFIN] 653 dynamic_printk Enables pr_debug()/dev_dbg() calls if
654 CONFIG_DYNAMIC_PRINTK_DEBUG has been enabled.
655 These can also be switched on/off via
656 <debugfs>/dynamic_printk/modules
657
658 earlycon= [KNL] Output early console device and options.
659 uart[8250],io,<addr>[,options]
660 uart[8250],mmio,<addr>[,options]
661 Start an early, polled-mode console on the 8250/16550
662 UART at the specified I/O port or MMIO address.
663 The options are the same as for ttyS, above.
664
665 earlyprintk= [X86,SH,BLACKFIN]
684 earlyprintk=vga 666 earlyprintk=vga
685 earlyprintk=serial[,ttySn[,baudrate]] 667 earlyprintk=serial[,ttySn[,baudrate]]
686 earlyprintk=dbgp 668 earlyprintk=dbgp
@@ -715,12 +697,23 @@ and is between 256 and 4096 characters. It is defined in the file
715 See Documentation/block/as-iosched.txt and 697 See Documentation/block/as-iosched.txt and
716 Documentation/block/deadline-iosched.txt for details. 698 Documentation/block/deadline-iosched.txt for details.
717 699
718 elfcorehdr= [IA64,PPC,SH,X86-32,X86_64] 700 elfcorehdr= [IA64,PPC,SH,X86]
719 Specifies physical address of start of kernel core 701 Specifies physical address of start of kernel core
720 image elf header. Generally kexec loader will 702 image elf header. Generally kexec loader will
721 pass this option to capture kernel. 703 pass this option to capture kernel.
722 See Documentation/kdump/kdump.txt for details. 704 See Documentation/kdump/kdump.txt for details.
723 705
706 enable_mtrr_cleanup [X86]
707 The kernel tries to adjust MTRR layout from continuous
708 to discrete, to make X server driver able to add WB
709 entry later. This parameter enables that.
710
711 enable_timer_pin_1 [X86]
712 Enable PIN 1 of APIC timer
713 Can be useful to work around chipset bugs
714 (in particular on some ATI chipsets).
715 The kernel tries to set a reasonable default.
716
724 enforcing [SELINUX] Set initial enforcing status. 717 enforcing [SELINUX] Set initial enforcing status.
725 Format: {"0" | "1"} 718 Format: {"0" | "1"}
726 See security/selinux/Kconfig help text. 719 See security/selinux/Kconfig help text.
@@ -788,7 +781,7 @@ and is between 256 and 4096 characters. It is defined in the file
788 781
789 hashdist= [KNL,NUMA] Large hashes allocated during boot 782 hashdist= [KNL,NUMA] Large hashes allocated during boot
790 are distributed across NUMA nodes. Defaults on 783 are distributed across NUMA nodes. Defaults on
791 for IA-64, off otherwise. 784 for 64bit NUMA, off otherwise.
792 Format: 0 | 1 (for off | on) 785 Format: 0 | 1 (for off | on)
793 786
794 hcl= [IA-64] SGI's Hardware Graph compatibility layer 787 hcl= [IA-64] SGI's Hardware Graph compatibility layer
@@ -808,6 +801,16 @@ and is between 256 and 4096 characters. It is defined in the file
808 hisax= [HW,ISDN] 801 hisax= [HW,ISDN]
809 See Documentation/isdn/README.HiSax. 802 See Documentation/isdn/README.HiSax.
810 803
804 hlt [BUGS=ARM,SH]
805
806 hpet= [X86-32,HPET] option to control HPET usage
807 Format: { enable (default) | disable | force |
808 verbose }
809 disable: disable HPET and use PIT instead
810 force: allow force enabled of undocumented chips (ICH4,
811 VIA, nVidia)
812 verbose: show contents of HPET registers during setup
813
811 hugepages= [HW,X86-32,IA-64] HugeTLB pages to allocate at boot. 814 hugepages= [HW,X86-32,IA-64] HugeTLB pages to allocate at boot.
812 hugepagesz= [HW,IA-64,PPC,X86-64] The size of the HugeTLB pages. 815 hugepagesz= [HW,IA-64,PPC,X86-64] The size of the HugeTLB pages.
813 On x86-64 and powerpc, this option can be specified 816 On x86-64 and powerpc, this option can be specified
@@ -817,18 +820,18 @@ and is between 256 and 4096 characters. It is defined in the file
817 (when the CPU supports the "pdpe1gb" cpuinfo flag) 820 (when the CPU supports the "pdpe1gb" cpuinfo flag)
818 Note that 1GB pages can only be allocated at boot time 821 Note that 1GB pages can only be allocated at boot time
819 using hugepages= and not freed afterwards. 822 using hugepages= and not freed afterwards.
820 default_hugepagesz=
821 [same as hugepagesz=] The size of the default
822 HugeTLB page size. This is the size represented by
823 the legacy /proc/ hugepages APIs, used for SHM, and
824 default size when mounting hugetlbfs filesystems.
825 Defaults to the default architecture's huge page size
826 if not specified.
827
828 hlt [BUGS=ARM,SH]
829 823
830 hvc_iucv= [S390] Number of z/VM IUCV hypervisor console (HVC) 824 hvc_iucv= [S390] Number of z/VM IUCV hypervisor console (HVC)
831 terminal devices. Valid values: 0..8 825 terminal devices. Valid values: 0..8
826 hvc_iucv_allow= [S390] Comma-separated list of z/VM user IDs.
827 If specified, z/VM IUCV HVC accepts connections
828 from listed z/VM user IDs only.
829
830 i2c_bus= [HW] Override the default board specific I2C bus speed
831 or register an additional I2C bus that is not
832 registered from board initialization code.
833 Format:
834 <bus_id>,<clkrate>
832 835
833 i8042.debug [HW] Toggle i8042 debug mode 836 i8042.debug [HW] Toggle i8042 debug mode
834 i8042.direct [HW] Put keyboard port into non-translated mode 837 i8042.direct [HW] Put keyboard port into non-translated mode
@@ -877,6 +880,9 @@ and is between 256 and 4096 characters. It is defined in the file
877 idebus= [HW] (E)IDE subsystem - VLB/PCI bus speed 880 idebus= [HW] (E)IDE subsystem - VLB/PCI bus speed
878 See Documentation/ide/ide.txt. 881 See Documentation/ide/ide.txt.
879 882
883 ide-pci-generic.all-generic-ide [HW] (E)IDE subsystem
884 Claim all unknown PCI IDE storage controllers.
885
880 idle= [X86] 886 idle= [X86]
881 Format: idle=poll, idle=mwait, idle=halt, idle=nomwait 887 Format: idle=poll, idle=mwait, idle=halt, idle=nomwait
882 Poll forces a polling idle loop that can slightly 888 Poll forces a polling idle loop that can slightly
@@ -892,9 +898,6 @@ and is between 256 and 4096 characters. It is defined in the file
892 In such case C2/C3 won't be used again. 898 In such case C2/C3 won't be used again.
893 idle=nomwait: Disable mwait for CPU C-states 899 idle=nomwait: Disable mwait for CPU C-states
894 900
895 ide-pci-generic.all-generic-ide [HW] (E)IDE subsystem
896 Claim all unknown PCI IDE storage controllers.
897
898 ignore_loglevel [KNL] 901 ignore_loglevel [KNL]
899 Ignore loglevel setting - this will print /all/ 902 Ignore loglevel setting - this will print /all/
900 kernel messages to the console. Useful for debugging. 903 kernel messages to the console. Useful for debugging.
@@ -902,6 +905,15 @@ and is between 256 and 4096 characters. It is defined in the file
902 ihash_entries= [KNL] 905 ihash_entries= [KNL]
903 Set number of hash buckets for inode cache. 906 Set number of hash buckets for inode cache.
904 907
908 ima_audit= [IMA]
909 Format: { "0" | "1" }
910 0 -- integrity auditing messages. (Default)
911 1 -- enable informational integrity auditing messages.
912
913 ima_hash= [IMA]
914 Formt: { "sha1" | "md5" }
915 default: "sha1"
916
905 in2000= [HW,SCSI] 917 in2000= [HW,SCSI]
906 See header of drivers/scsi/in2000.c. 918 See header of drivers/scsi/in2000.c.
907 919
@@ -919,25 +931,6 @@ and is between 256 and 4096 characters. It is defined in the file
919 inport.irq= [HW] Inport (ATI XL and Microsoft) busmouse driver 931 inport.irq= [HW] Inport (ATI XL and Microsoft) busmouse driver
920 Format: <irq> 932 Format: <irq>
921 933
922 inttest= [IA64]
923
924 iomem= Disable strict checking of access to MMIO memory
925 strict regions from userspace.
926 relaxed
927
928 iommu= [x86]
929 off
930 force
931 noforce
932 biomerge
933 panic
934 nopanic
935 merge
936 nomerge
937 forcesac
938 soft
939
940
941 intel_iommu= [DMAR] Intel IOMMU driver (DMAR) option 934 intel_iommu= [DMAR] Intel IOMMU driver (DMAR) option
942 on 935 on
943 Enable intel iommu driver. 936 Enable intel iommu driver.
@@ -961,7 +954,29 @@ and is between 256 and 4096 characters. It is defined in the file
961 result in a hardware IOTLB flush operation as opposed 954 result in a hardware IOTLB flush operation as opposed
962 to batching them for performance. 955 to batching them for performance.
963 956
964 io_delay= [X86-32,X86-64] I/O delay method 957 inttest= [IA64]
958
959 iomem= Disable strict checking of access to MMIO memory
960 strict regions from userspace.
961 relaxed
962
963 iommu= [x86]
964 off
965 force
966 noforce
967 biomerge
968 panic
969 nopanic
970 merge
971 nomerge
972 forcesac
973 soft
974
975 io7= [HW] IO7 for Marvel based alpha systems
976 See comment before marvel_specify_io7 in
977 arch/alpha/kernel/core_marvel.c.
978
979 io_delay= [X86] I/O delay method
965 0x80 980 0x80
966 Standard port 0x80 based delay 981 Standard port 0x80 based delay
967 0xed 982 0xed
@@ -971,10 +986,6 @@ and is between 256 and 4096 characters. It is defined in the file
971 none 986 none
972 No delay 987 No delay
973 988
974 io7= [HW] IO7 for Marvel based alpha systems
975 See comment before marvel_specify_io7 in
976 arch/alpha/kernel/core_marvel.c.
977
978 ip= [IP_PNP] 989 ip= [IP_PNP]
979 See Documentation/filesystems/nfsroot.txt. 990 See Documentation/filesystems/nfsroot.txt.
980 991
@@ -985,12 +996,6 @@ and is between 256 and 4096 characters. It is defined in the file
985 ips= [HW,SCSI] Adaptec / IBM ServeRAID controller 996 ips= [HW,SCSI] Adaptec / IBM ServeRAID controller
986 See header of drivers/scsi/ips.c. 997 See header of drivers/scsi/ips.c.
987 998
988 ports= [IP_VS_FTP] IPVS ftp helper module
989 Default is 21.
990 Up to 8 (IP_VS_APP_MAX_PORTS) ports
991 may be specified.
992 Format: <port>,<port>....
993
994 irqfixup [HW] 999 irqfixup [HW]
995 When an interrupt is not handled search all handlers 1000 When an interrupt is not handled search all handlers
996 for it. Intended to get systems with badly broken 1001 for it. Intended to get systems with badly broken
@@ -1031,7 +1036,9 @@ and is between 256 and 4096 characters. It is defined in the file
1031 js= [HW,JOY] Analog joystick 1036 js= [HW,JOY] Analog joystick
1032 See Documentation/input/joystick.txt. 1037 See Documentation/input/joystick.txt.
1033 1038
1034 kernelcore=nn[KMG] [KNL,X86-32,IA-64,PPC,X86-64] This parameter 1039 keepinitrd [HW,ARM]
1040
1041 kernelcore=nn[KMG] [KNL,X86,IA-64,PPC] This parameter
1035 specifies the amount of memory usable by the kernel 1042 specifies the amount of memory usable by the kernel
1036 for non-movable allocations. The requested amount is 1043 for non-movable allocations. The requested amount is
1037 spread evenly throughout all nodes in the system. The 1044 spread evenly throughout all nodes in the system. The
@@ -1047,20 +1054,14 @@ and is between 256 and 4096 characters. It is defined in the file
1047 use the HighMem zone if it exists, and the Normal 1054 use the HighMem zone if it exists, and the Normal
1048 zone if it does not. 1055 zone if it does not.
1049 1056
1050 movablecore=nn[KMG] [KNL,X86-32,IA-64,PPC,X86-64] This parameter 1057 kmemtrace.enable= [KNL,KMEMTRACE] Format: { yes | no }
1051 is similar to kernelcore except it specifies the 1058 Controls whether kmemtrace is enabled
1052 amount of memory used for migratable allocations. 1059 at boot-time.
1053 If both kernelcore and movablecore is specified,
1054 then kernelcore will be at *least* the specified
1055 value but may be more. If movablecore on its own
1056 is specified, the administrator must be careful
1057 that the amount of memory usable for all allocations
1058 is not too small.
1059 1060
1060 keepinitrd [HW,ARM] 1061 kmemtrace.subbufs=n [KNL,KMEMTRACE] Overrides the number of
1061 1062 subbufs kmemtrace's relay channel has. Set this
1062 kstack=N [X86-32,X86-64] Print N words from the kernel stack 1063 higher than default (KMEMTRACE_N_SUBBUFS in code) if
1063 in oops dumps. 1064 you experience buffer overruns.
1064 1065
1065 kgdboc= [HW] kgdb over consoles. 1066 kgdboc= [HW] kgdb over consoles.
1066 Requires a tty driver that supports console polling. 1067 Requires a tty driver that supports console polling.
@@ -1071,6 +1072,9 @@ and is between 256 and 4096 characters. It is defined in the file
1071 Configure the RouterBoard 532 series on-chip 1072 Configure the RouterBoard 532 series on-chip
1072 Ethernet adapter MAC address. 1073 Ethernet adapter MAC address.
1073 1074
1075 kstack=N [X86] Print N words from the kernel stack
1076 in oops dumps.
1077
1074 l2cr= [PPC] 1078 l2cr= [PPC]
1075 1079
1076 l3cr= [PPC] 1080 l3cr= [PPC]
@@ -1078,7 +1082,7 @@ and is between 256 and 4096 characters. It is defined in the file
1078 lapic [X86-32,APIC] Enable the local APIC even if BIOS 1082 lapic [X86-32,APIC] Enable the local APIC even if BIOS
1079 disabled it. 1083 disabled it.
1080 1084
1081 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
1082 in C2 power state. 1086 in C2 power state.
1083 1087
1084 libata.dma= [LIBATA] DMA control 1088 libata.dma= [LIBATA] DMA control
@@ -1216,9 +1220,8 @@ and is between 256 and 4096 characters. It is defined in the file
1216 (machvec) in a generic kernel. 1220 (machvec) in a generic kernel.
1217 Example: machvec=hpzx1_swiotlb 1221 Example: machvec=hpzx1_swiotlb
1218 1222
1219 max_loop= [LOOP] Maximum number of loopback devices that can 1223 max_addr=nn[KMG] [KNL,BOOT,ia64] All physical memory greater
1220 be mounted 1224 than or equal to this physical address is ignored.
1221 Format: <1-256>
1222 1225
1223 maxcpus= [SMP] Maximum number of processors that an SMP kernel 1226 maxcpus= [SMP] Maximum number of processors that an SMP kernel
1224 should make use of. maxcpus=n : n >= 0 limits the 1227 should make use of. maxcpus=n : n >= 0 limits the
@@ -1226,8 +1229,9 @@ and is between 256 and 4096 characters. It is defined in the file
1226 it is equivalent to "nosmp", which also disables 1229 it is equivalent to "nosmp", which also disables
1227 the IO APIC. 1230 the IO APIC.
1228 1231
1229 max_addr=nn[KMG] [KNL,BOOT,ia64] All physical memory greater than 1232 max_loop= [LOOP] Maximum number of loopback devices that can
1230 or equal to this physical address is ignored. 1233 be mounted
1234 Format: <1-256>
1231 1235
1232 max_luns= [SCSI] Maximum number of LUNs to probe. 1236 max_luns= [SCSI] Maximum number of LUNs to probe.
1233 Should be between 1 and 2^32-1. 1237 Should be between 1 and 2^32-1.
@@ -1263,7 +1267,7 @@ and is between 256 and 4096 characters. It is defined in the file
1263 [KNL,SH] Allow user to override the default size for 1267 [KNL,SH] Allow user to override the default size for
1264 per-device physically contiguous DMA buffers. 1268 per-device physically contiguous DMA buffers.
1265 1269
1266 memmap=exactmap [KNL,X86-32,X86_64] Enable setting of an exact 1270 memmap=exactmap [KNL,X86] Enable setting of an exact
1267 E820 memory map, as specified by the user. 1271 E820 memory map, as specified by the user.
1268 Such memmap=exactmap lines can be constructed based on 1272 Such memmap=exactmap lines can be constructed based on
1269 BIOS output or other requirements. See the memmap=nn@ss 1273 BIOS output or other requirements. See the memmap=nn@ss
@@ -1310,8 +1314,13 @@ and is between 256 and 4096 characters. It is defined in the file
1310 1314
1311 memtest= [KNL,X86] Enable memtest 1315 memtest= [KNL,X86] Enable memtest
1312 Format: <integer> 1316 Format: <integer>
1313 range: 0,4 : pattern number
1314 default : 0 <disable> 1317 default : 0 <disable>
1318 Specifies the number of memtest passes to be
1319 performed. Each pass selects another test
1320 pattern from a given set of patterns. Memtest
1321 fills the memory with this pattern, validates
1322 memory contents and reserves bad memory
1323 regions that are detected.
1315 1324
1316 meye.*= [HW] Set MotionEye Camera parameters 1325 meye.*= [HW] Set MotionEye Camera parameters
1317 See Documentation/video4linux/meye.txt. 1326 See Documentation/video4linux/meye.txt.
@@ -1349,6 +1358,16 @@ and is between 256 and 4096 characters. It is defined in the file
1349 mousedev.yres= [MOUSE] Vertical screen resolution, used for devices 1358 mousedev.yres= [MOUSE] Vertical screen resolution, used for devices
1350 reporting absolute coordinates, such as tablets 1359 reporting absolute coordinates, such as tablets
1351 1360
1361 movablecore=nn[KMG] [KNL,X86,IA-64,PPC] This parameter
1362 is similar to kernelcore except it specifies the
1363 amount of memory used for migratable allocations.
1364 If both kernelcore and movablecore is specified,
1365 then kernelcore will be at *least* the specified
1366 value but may be more. If movablecore on its own
1367 is specified, the administrator must be careful
1368 that the amount of memory usable for all allocations
1369 is not too small.
1370
1352 mpu401= [HW,OSS] 1371 mpu401= [HW,OSS]
1353 Format: <io>,<irq> 1372 Format: <io>,<irq>
1354 1373
@@ -1370,6 +1389,23 @@ and is between 256 and 4096 characters. It is defined in the file
1370 [HW] Make the MicroTouch USB driver use raw coordinates 1389 [HW] Make the MicroTouch USB driver use raw coordinates
1371 ('y', default) or cooked coordinates ('n') 1390 ('y', default) or cooked coordinates ('n')
1372 1391
1392 mtrr_chunk_size=nn[KMG] [X86]
1393 used for mtrr cleanup. It is largest continous chunk
1394 that could hold holes aka. UC entries.
1395
1396 mtrr_gran_size=nn[KMG] [X86]
1397 Used for mtrr cleanup. It is granularity of mtrr block.
1398 Default is 1.
1399 Large value could prevent small alignment from
1400 using up MTRRs.
1401
1402 mtrr_spare_reg_nr=n [X86]
1403 Format: <integer>
1404 Range: 0,7 : spare reg number
1405 Default : 1
1406 Used for mtrr cleanup. It is spare mtrr entries number.
1407 Set to 2 or more if your graphical card needs more.
1408
1373 n2= [NET] SDL Inc. RISCom/N2 synchronous serial card 1409 n2= [NET] SDL Inc. RISCom/N2 synchronous serial card
1374 1410
1375 NCR_D700= [HW,SCSI] 1411 NCR_D700= [HW,SCSI]
@@ -1424,17 +1460,19 @@ and is between 256 and 4096 characters. It is defined in the file
1424 when a NMI is triggered. 1460 when a NMI is triggered.
1425 Format: [state][,regs][,debounce][,die] 1461 Format: [state][,regs][,debounce][,die]
1426 1462
1427 nmi_watchdog= [KNL,BUGS=X86-32,X86-64] Debugging features for SMP kernels 1463 nmi_watchdog= [KNL,BUGS=X86] Debugging features for SMP kernels
1428 Format: [panic,][num] 1464 Format: [panic,][num]
1429 Valid num: 0,1,2 1465 Valid num: 0,1,2
1430 0 - turn nmi_watchdog off 1466 0 - turn nmi_watchdog off
1431 1 - use the IO-APIC timer for the NMI watchdog 1467 1 - use the IO-APIC timer for the NMI watchdog
1432 2 - use the local APIC for the NMI watchdog using 1468 2 - use the local APIC for the NMI watchdog using
1433 a performance counter. Note: This will use one performance 1469 a performance counter. Note: This will use one
1434 counter and the local APIC's performance vector. 1470 performance counter and the local APIC's performance
1435 When panic is specified panic when an NMI watchdog timeout occurs. 1471 vector.
1436 This is useful when you use a panic=... timeout and need the box 1472 When panic is specified, panic when an NMI watchdog
1437 quickly up again. 1473 timeout occurs.
1474 This is useful when you use a panic=... timeout and
1475 need the box quickly up again.
1438 Instead of 1 and 2 it is possible to use the following 1476 Instead of 1 and 2 it is possible to use the following
1439 symbolic names: lapic and ioapic 1477 symbolic names: lapic and ioapic
1440 Example: nmi_watchdog=2 or nmi_watchdog=panic,lapic 1478 Example: nmi_watchdog=2 or nmi_watchdog=panic,lapic
@@ -1443,6 +1481,16 @@ and is between 256 and 4096 characters. It is defined in the file
1443 emulation library even if a 387 maths coprocessor 1481 emulation library even if a 387 maths coprocessor
1444 is present. 1482 is present.
1445 1483
1484 no_console_suspend
1485 [HW] Never suspend the console
1486 Disable suspending of consoles during suspend and
1487 hibernate operations. Once disabled, debugging
1488 messages can reach various consoles while the rest
1489 of the system is being put to sleep (ie, while
1490 debugging driver suspend/resume hooks). This may
1491 not work reliably with all consoles, but is known
1492 to work with serial and VGA consoles.
1493
1446 noaliencache [MM, NUMA, SLAB] Disables the allocation of alien 1494 noaliencache [MM, NUMA, SLAB] Disables the allocation of alien
1447 caches in the slab allocator. Saves per-node memory, 1495 caches in the slab allocator. Saves per-node memory,
1448 but will impact performance. 1496 but will impact performance.
@@ -1457,17 +1505,19 @@ and is between 256 and 4096 characters. It is defined in the file
1457 1505
1458 nocache [ARM] 1506 nocache [ARM]
1459 1507
1508 noclflush [BUGS=X86] Don't use the CLFLUSH instruction
1509
1460 nodelayacct [KNL] Disable per-task delay accounting 1510 nodelayacct [KNL] Disable per-task delay accounting
1461 1511
1462 nodisconnect [HW,SCSI,M68K] Disables SCSI disconnects. 1512 nodisconnect [HW,SCSI,M68K] Disables SCSI disconnects.
1463 1513
1464 nodsp [SH] Disable hardware DSP at boot time. 1514 nodsp [SH] Disable hardware DSP at boot time.
1465 1515
1466 noefi [X86-32,X86-64] Disable EFI runtime services support. 1516 noefi [X86] Disable EFI runtime services support.
1467 1517
1468 noexec [IA-64] 1518 noexec [IA-64]
1469 1519
1470 noexec [X86-32,X86-64] 1520 noexec [X86]
1471 On X86-32 available only on PAE configured kernels. 1521 On X86-32 available only on PAE configured kernels.
1472 noexec=on: enable non-executable mappings (default) 1522 noexec=on: enable non-executable mappings (default)
1473 noexec=off: disable non-executable mappings 1523 noexec=off: disable non-executable mappings
@@ -1485,9 +1535,9 @@ and is between 256 and 4096 characters. It is defined in the file
1485 register save and restore. The kernel will only save 1535 register save and restore. The kernel will only save
1486 legacy floating-point registers on task switch. 1536 legacy floating-point registers on task switch.
1487 1537
1488 noclflush [BUGS=X86] Don't use the CLFLUSH instruction 1538 nohlt [BUGS=ARM,SH] Tells the kernel that the sleep(SH) or
1489 1539 wfi(ARM) instruction doesn't work correctly and not to
1490 nohlt [BUGS=ARM,SH] 1540 use it. This is also useful when using JTAG debugger.
1491 1541
1492 no-hlt [BUGS=X86-32] Tells the kernel that the hlt 1542 no-hlt [BUGS=X86-32] Tells the kernel that the hlt
1493 instruction doesn't work correctly and not to 1543 instruction doesn't work correctly and not to
@@ -1508,10 +1558,12 @@ and is between 256 and 4096 characters. It is defined in the file
1508 Valid arguments: on, off 1558 Valid arguments: on, off
1509 Default: on 1559 Default: on
1510 1560
1561 noiotrap [SH] Disables trapped I/O port accesses.
1562
1511 noirqdebug [X86-32] Disables the code which attempts to detect and 1563 noirqdebug [X86-32] Disables the code which attempts to detect and
1512 disable unhandled interrupt sources. 1564 disable unhandled interrupt sources.
1513 1565
1514 no_timer_check [X86-32,X86_64,APIC] Disables the code which tests for 1566 no_timer_check [X86,APIC] Disables the code which tests for
1515 broken timer IRQ sources. 1567 broken timer IRQ sources.
1516 1568
1517 noisapnp [ISAPNP] Disables ISA PnP code. 1569 noisapnp [ISAPNP] Disables ISA PnP code.
@@ -1527,12 +1579,6 @@ and is between 256 and 4096 characters. It is defined in the file
1527 1579
1528 nolapic_timer [X86-32,APIC] Do not use the local APIC timer. 1580 nolapic_timer [X86-32,APIC] Do not use the local APIC timer.
1529 1581
1530 nox2apic [X86-64,APIC] Do not enable x2APIC mode.
1531
1532 x2apic_phys [X86-64,APIC] Use x2apic physical mode instead of
1533 default x2apic cluster mode on platforms
1534 supporting x2apic.
1535
1536 noltlbs [PPC] Do not use large page/tlb entries for kernel 1582 noltlbs [PPC] Do not use large page/tlb entries for kernel
1537 lowmem mapping on PPC40x. 1583 lowmem mapping on PPC40x.
1538 1584
@@ -1543,6 +1589,9 @@ and is between 256 and 4096 characters. It is defined in the file
1543 nomfgpt [X86-32] Disable Multi-Function General Purpose 1589 nomfgpt [X86-32] Disable Multi-Function General Purpose
1544 Timer usage (for AMD Geode machines). 1590 Timer usage (for AMD Geode machines).
1545 1591
1592 norandmaps Don't use address space randomization. Equivalent to
1593 echo 0 > /proc/sys/kernel/randomize_va_space
1594
1546 noreplace-paravirt [X86-32,PV_OPS] Don't patch paravirt_ops 1595 noreplace-paravirt [X86-32,PV_OPS] Don't patch paravirt_ops
1547 1596
1548 noreplace-smp [X86-32,SMP] Don't replace SMP instructions 1597 noreplace-smp [X86-32,SMP] Don't replace SMP instructions
@@ -1567,7 +1616,7 @@ and is between 256 and 4096 characters. It is defined in the file
1567 nosoftlockup [KNL] Disable the soft-lockup detector. 1616 nosoftlockup [KNL] Disable the soft-lockup detector.
1568 1617
1569 noswapaccount [KNL] Disable accounting of swap in memory resource 1618 noswapaccount [KNL] Disable accounting of swap in memory resource
1570 controller. (See Documentation/controllers/memory.txt) 1619 controller. (See Documentation/cgroups/memory.txt)
1571 1620
1572 nosync [HW,M68K] Disables sync negotiation for all devices. 1621 nosync [HW,M68K] Disables sync negotiation for all devices.
1573 1622
@@ -1577,17 +1626,19 @@ and is between 256 and 4096 characters. It is defined in the file
1577 1626
1578 nowb [ARM] 1627 nowb [ARM]
1579 1628
1629 nox2apic [X86-64,APIC] Do not enable x2APIC mode.
1630
1580 nptcg= [IA64] Override max number of concurrent global TLB 1631 nptcg= [IA64] Override max number of concurrent global TLB
1581 purges which is reported from either PAL_VM_SUMMARY or 1632 purges which is reported from either PAL_VM_SUMMARY or
1582 SAL PALO. 1633 SAL PALO.
1583 1634
1635 nr_uarts= [SERIAL] maximum number of UARTs to be registered.
1636
1584 numa_zonelist_order= [KNL, BOOT] Select zonelist order for NUMA. 1637 numa_zonelist_order= [KNL, BOOT] Select zonelist order for NUMA.
1585 one of ['zone', 'node', 'default'] can be specified 1638 one of ['zone', 'node', 'default'] can be specified
1586 This can be set from sysctl after boot. 1639 This can be set from sysctl after boot.
1587 See Documentation/sysctl/vm.txt for details. 1640 See Documentation/sysctl/vm.txt for details.
1588 1641
1589 nr_uarts= [SERIAL] maximum number of UARTs to be registered.
1590
1591 ohci1394_dma=early [HW] enable debugging via the ohci1394 driver. 1642 ohci1394_dma=early [HW] enable debugging via the ohci1394 driver.
1592 See Documentation/debugging-via-ohci1394.txt for more 1643 See Documentation/debugging-via-ohci1394.txt for more
1593 info. 1644 info.
@@ -1659,6 +1710,8 @@ and is between 256 and 4096 characters. It is defined in the file
1659 See also Documentation/blockdev/paride.txt. 1710 See also Documentation/blockdev/paride.txt.
1660 1711
1661 pci=option[,option...] [PCI] various PCI subsystem options: 1712 pci=option[,option...] [PCI] various PCI subsystem options:
1713 earlydump [X86] dump PCI config space before the kernel
1714 changes anything
1662 off [X86] don't probe for the PCI bus 1715 off [X86] don't probe for the PCI bus
1663 bios [X86-32] force use of PCI BIOS, don't access 1716 bios [X86-32] force use of PCI BIOS, don't access
1664 the hardware directly. Use this if your machine 1717 the hardware directly. Use this if your machine
@@ -1676,7 +1729,7 @@ and is between 256 and 4096 characters. It is defined in the file
1676 disable the use of PCIE advanced error reporting. 1729 disable the use of PCIE advanced error reporting.
1677 nodomains [PCI] Disable support for multiple PCI 1730 nodomains [PCI] Disable support for multiple PCI
1678 root domains (aka PCI segments, in ACPI-speak). 1731 root domains (aka PCI segments, in ACPI-speak).
1679 nommconf [X86-32,X86_64] Disable use of MMCONFIG for PCI 1732 nommconf [X86] Disable use of MMCONFIG for PCI
1680 Configuration 1733 Configuration
1681 nomsi [MSI] If the PCI_MSI kernel config parameter is 1734 nomsi [MSI] If the PCI_MSI kernel config parameter is
1682 enabled, this kernel boot option can be used to 1735 enabled, this kernel boot option can be used to
@@ -1758,6 +1811,15 @@ and is between 256 and 4096 characters. It is defined in the file
1758 cbmemsize=nn[KMG] The fixed amount of bus space which is 1811 cbmemsize=nn[KMG] The fixed amount of bus space which is
1759 reserved for the CardBus bridge's memory 1812 reserved for the CardBus bridge's memory
1760 window. The default value is 64 megabytes. 1813 window. The default value is 64 megabytes.
1814 resource_alignment=
1815 Format:
1816 [<order of align>@][<domain>:]<bus>:<slot>.<func>[; ...]
1817 Specifies alignment and device to reassign
1818 aligned memory resources.
1819 If <order of align> is not specified,
1820 PAGE_SIZE is used as alignment.
1821 PCI-PCI bridge can be specified, if resource
1822 windows need to be expanded.
1761 1823
1762 pcie_aspm= [PCIE] Forcibly enable or disable PCIe Active State Power 1824 pcie_aspm= [PCIE] Forcibly enable or disable PCIe Active State Power
1763 Management. 1825 Management.
@@ -1816,10 +1878,11 @@ and is between 256 and 4096 characters. It is defined in the file
1816 autoconfiguration. 1878 autoconfiguration.
1817 Ranges are in pairs (memory base and size). 1879 Ranges are in pairs (memory base and size).
1818 1880
1819 dynamic_printk Enables pr_debug()/dev_dbg() calls if 1881 ports= [IP_VS_FTP] IPVS ftp helper module
1820 CONFIG_DYNAMIC_PRINTK_DEBUG has been enabled. 1882 Default is 21.
1821 These can also be switched on/off via 1883 Up to 8 (IP_VS_APP_MAX_PORTS) ports
1822 <debugfs>/dynamic_printk/modules 1884 may be specified.
1885 Format: <port>,<port>....
1823 1886
1824 print-fatal-signals= 1887 print-fatal-signals=
1825 [KNL] debug: print fatal signals 1888 [KNL] debug: print fatal signals
@@ -1830,6 +1893,14 @@ and is between 256 and 4096 characters. It is defined in the file
1830 printk.time= Show timing data prefixed to each printk message line 1893 printk.time= Show timing data prefixed to each printk message line
1831 Format: <bool> (1/Y/y=enable, 0/N/n=disable) 1894 Format: <bool> (1/Y/y=enable, 0/N/n=disable)
1832 1895
1896 processor.max_cstate= [HW,ACPI]
1897 Limit processor to maximum C-state
1898 max_cstate=9 overrides any DMI blacklist limit.
1899
1900 processor.nocst [HW,ACPI]
1901 Ignore the _CST method to determine C-states,
1902 instead using the legacy FADT method
1903
1833 profile= [KNL] Enable kernel profiling via /proc/profile 1904 profile= [KNL] Enable kernel profiling via /proc/profile
1834 Format: [schedule,]<number> 1905 Format: [schedule,]<number>
1835 Param: "schedule" - profile schedule points. 1906 Param: "schedule" - profile schedule points.
@@ -1839,14 +1910,6 @@ and is between 256 and 4096 characters. It is defined in the file
1839 Requires CONFIG_SCHEDSTATS 1910 Requires CONFIG_SCHEDSTATS
1840 Param: "kvm" - profile VM exits. 1911 Param: "kvm" - profile VM exits.
1841 1912
1842 processor.max_cstate= [HW,ACPI]
1843 Limit processor to maximum C-state
1844 max_cstate=9 overrides any DMI blacklist limit.
1845
1846 processor.nocst [HW,ACPI]
1847 Ignore the _CST method to determine C-states,
1848 instead using the legacy FADT method
1849
1850 prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk 1913 prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk
1851 before loading. 1914 before loading.
1852 See Documentation/blockdev/ramdisk.txt. 1915 See Documentation/blockdev/ramdisk.txt.
@@ -1911,7 +1974,7 @@ and is between 256 and 4096 characters. It is defined in the file
1911 1974
1912 relax_domain_level= 1975 relax_domain_level=
1913 [KNL, SMP] Set scheduler's default relax_domain_level. 1976 [KNL, SMP] Set scheduler's default relax_domain_level.
1914 See Documentation/cpusets.txt. 1977 See Documentation/cgroups/cpusets.txt.
1915 1978
1916 reserve= [KNL,BUGS] Force the kernel to ignore some iomem area 1979 reserve= [KNL,BUGS] Force the kernel to ignore some iomem area
1917 1980
@@ -2000,7 +2063,13 @@ and is between 256 and 4096 characters. It is defined in the file
2000 allowing boot to proceed. none ignores them, expecting 2063 allowing boot to proceed. none ignores them, expecting
2001 user space to do the scan. 2064 user space to do the scan.
2002 2065
2003 selinux [SELINUX] Disable or enable SELinux at boot time. 2066 security= [SECURITY] Choose a security module to enable at boot.
2067 If this boot parameter is not specified, only the first
2068 security module asking for security registration will be
2069 loaded. An invalid security module name will be treated
2070 as if no module has been chosen.
2071
2072 selinux= [SELINUX] Disable or enable SELinux at boot time.
2004 Format: { "0" | "1" } 2073 Format: { "0" | "1" }
2005 See security/selinux/Kconfig help text. 2074 See security/selinux/Kconfig help text.
2006 0 -- disable. 2075 0 -- disable.
@@ -2009,15 +2078,6 @@ and is between 256 and 4096 characters. It is defined in the file
2009 If enabled at boot time, /selinux/disable can be used 2078 If enabled at boot time, /selinux/disable can be used
2010 later to disable prior to initial policy load. 2079 later to disable prior to initial policy load.
2011 2080
2012 selinux_compat_net =
2013 [SELINUX] Set initial selinux_compat_net flag value.
2014 Format: { "0" | "1" }
2015 0 -- use new secmark-based packet controls
2016 1 -- use legacy packet controls
2017 Default value is 0 (preferred).
2018 Value can be changed at runtime via
2019 /selinux/compat_net.
2020
2021 serialnumber [BUGS=X86-32] 2081 serialnumber [BUGS=X86-32]
2022 2082
2023 shapers= [NET] 2083 shapers= [NET]
@@ -2329,6 +2389,8 @@ and is between 256 and 4096 characters. It is defined in the file
2329 2389
2330 tp720= [HW,PS2] 2390 tp720= [HW,PS2]
2331 2391
2392 trace_buf_size=nn[KMG] [ftrace] will set tracing buffer size.
2393
2332 trix= [HW,OSS] MediaTrix AudioTrix Pro 2394 trix= [HW,OSS] MediaTrix AudioTrix Pro
2333 Format: 2395 Format:
2334 <io>,<irq>,<dma>,<dma2>,<sb_io>,<sb_irq>,<sb_dma>,<mpu_io>,<mpu_irq> 2396 <io>,<irq>,<dma>,<dma2>,<sb_io>,<sb_irq>,<sb_dma>,<mpu_io>,<mpu_irq>
@@ -2364,7 +2426,7 @@ and is between 256 and 4096 characters. It is defined in the file
2364 reported either. 2426 reported either.
2365 2427
2366 unknown_nmi_panic 2428 unknown_nmi_panic
2367 [X86-32,X86-64] 2429 [X86]
2368 Set unknown_nmi_panic=1 early on boot. 2430 Set unknown_nmi_panic=1 early on boot.
2369 2431
2370 usbcore.autosuspend= 2432 usbcore.autosuspend=
@@ -2431,15 +2493,12 @@ and is between 256 and 4096 characters. It is defined in the file
2431 medium is write-protected). 2493 medium is write-protected).
2432 Example: quirks=0419:aaf5:rl,0421:0433:rc 2494 Example: quirks=0419:aaf5:rl,0421:0433:rc
2433 2495
2434 add_efi_memmap [EFI; x86-32,X86-64] Include EFI memory map in 2496 vdso= [X86,SH]
2435 kernel's map of available physical RAM.
2436
2437 vdso= [X86-32,SH,x86-64]
2438 vdso=2: enable compat VDSO (default with COMPAT_VDSO) 2497 vdso=2: enable compat VDSO (default with COMPAT_VDSO)
2439 vdso=1: enable VDSO (default) 2498 vdso=1: enable VDSO (default)
2440 vdso=0: disable VDSO mapping 2499 vdso=0: disable VDSO mapping
2441 2500
2442 vdso32= [X86-32,X86-64] 2501 vdso32= [X86]
2443 vdso32=2: enable compat VDSO (default with COMPAT_VDSO) 2502 vdso32=2: enable compat VDSO (default with COMPAT_VDSO)
2444 vdso32=1: enable 32-bit VDSO (default) 2503 vdso32=1: enable 32-bit VDSO (default)
2445 vdso32=0: disable 32-bit VDSO mapping 2504 vdso32=0: disable 32-bit VDSO mapping
@@ -2472,6 +2531,31 @@ and is between 256 and 4096 characters. It is defined in the file
2472 vmpoff= [KNL,S390] Perform z/VM CP command after power off. 2531 vmpoff= [KNL,S390] Perform z/VM CP command after power off.
2473 Format: <command> 2532 Format: <command>
2474 2533
2534 vt.default_blu= [VT]
2535 Format: <blue0>,<blue1>,<blue2>,...,<blue15>
2536 Change the default blue palette of the console.
2537 This is a 16-member array composed of values
2538 ranging from 0-255.
2539
2540 vt.default_grn= [VT]
2541 Format: <green0>,<green1>,<green2>,...,<green15>
2542 Change the default green palette of the console.
2543 This is a 16-member array composed of values
2544 ranging from 0-255.
2545
2546 vt.default_red= [VT]
2547 Format: <red0>,<red1>,<red2>,...,<red15>
2548 Change the default red palette of the console.
2549 This is a 16-member array composed of values
2550 ranging from 0-255.
2551
2552 vt.default_utf8=
2553 [VT]
2554 Format=<0|1>
2555 Set system-wide default UTF-8 mode for all tty's.
2556 Default is 1, i.e. UTF-8 mode is enabled for all
2557 newly opened terminals.
2558
2475 waveartist= [HW,OSS] 2559 waveartist= [HW,OSS]
2476 Format: <io>,<irq>,<dma>,<dma2> 2560 Format: <io>,<irq>,<dma>,<dma2>
2477 2561
@@ -2484,6 +2568,10 @@ and is between 256 and 4096 characters. It is defined in the file
2484 wdt= [WDT] Watchdog 2568 wdt= [WDT] Watchdog
2485 See Documentation/watchdog/wdt.txt. 2569 See Documentation/watchdog/wdt.txt.
2486 2570
2571 x2apic_phys [X86-64,APIC] Use x2apic physical mode instead of
2572 default x2apic cluster mode on platforms
2573 supporting x2apic.
2574
2487 xd= [HW,XT] Original XT pre-IDE (RLL encoded) disks. 2575 xd= [HW,XT] Original XT pre-IDE (RLL encoded) disks.
2488 xd_geo= See header of drivers/block/xd.c. 2576 xd_geo= See header of drivers/block/xd.c.
2489 2577
@@ -2491,9 +2579,6 @@ and is between 256 and 4096 characters. It is defined in the file
2491 Format: 2579 Format:
2492 <irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]] 2580 <irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
2493 2581
2494 norandmaps Don't use address space randomization. Equivalent to
2495 echo 0 > /proc/sys/kernel/randomize_va_space
2496
2497______________________________________________________________________ 2582______________________________________________________________________
2498 2583
2499TODO: 2584TODO: