diff options
Diffstat (limited to 'Documentation/kernel-parameters.txt')
-rw-r--r-- | Documentation/kernel-parameters.txt | 144 |
1 files changed, 66 insertions, 78 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 343e0f0f84b6..e0f346d201ed 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt | |||
@@ -100,7 +100,7 @@ parameter is applicable: | |||
100 | X86-32 X86-32, aka i386 architecture is enabled. | 100 | X86-32 X86-32, aka i386 architecture is enabled. |
101 | X86-64 X86-64 architecture is enabled. | 101 | X86-64 X86-64 architecture is enabled. |
102 | More X86-64 boot options can be found in | 102 | More X86-64 boot options can be found in |
103 | Documentation/x86_64/boot-options.txt . | 103 | Documentation/x86/x86_64/boot-options.txt . |
104 | X86 Either 32bit or 64bit x86 (same as X86-32+X86-64) | 104 | X86 Either 32bit or 64bit x86 (same as X86-32+X86-64) |
105 | 105 | ||
106 | In addition, the following text indicates that the option: | 106 | In addition, the following text indicates that the option: |
@@ -112,10 +112,10 @@ In addition, the following text indicates that the option: | |||
112 | Parameters denoted with BOOT are actually interpreted by the boot | 112 | Parameters denoted with BOOT are actually interpreted by the boot |
113 | loader, and have no meaning to the kernel directly. | 113 | loader, and have no meaning to the kernel directly. |
114 | Do not modify the syntax of boot loader parameters without extreme | 114 | Do not modify the syntax of boot loader parameters without extreme |
115 | need or coordination with <Documentation/i386/boot.txt>. | 115 | need or coordination with <Documentation/x86/i386/boot.txt>. |
116 | 116 | ||
117 | There are also arch-specific kernel-parameters not documented here. | 117 | There are also arch-specific kernel-parameters not documented here. |
118 | See for example <Documentation/x86_64/boot-options.txt>. | 118 | See for example <Documentation/x86/x86_64/boot-options.txt>. |
119 | 119 | ||
120 | Note that ALL kernel parameters listed below are CASE SENSITIVE, and that | 120 | Note that ALL kernel parameters listed below are CASE SENSITIVE, and that |
121 | a trailing = on the name of any parameter states that that parameter will | 121 | a trailing = on the name of any parameter states that that parameter will |
@@ -198,59 +198,42 @@ and is between 256 and 4096 characters. It is defined in the file | |||
198 | that require a timer override, but don't have | 198 | that require a timer override, but don't have |
199 | HPET | 199 | HPET |
200 | 200 | ||
201 | acpi.debug_layer= [HW,ACPI] | 201 | acpi_backlight= [HW,ACPI] |
202 | Format: <int> | 202 | acpi_backlight=vendor |
203 | Each bit of the <int> indicates an ACPI debug layer, | 203 | acpi_backlight=video |
204 | 1: enable, 0: disable. It is useful for boot time | 204 | If set to vendor, prefer vendor specific driver |
205 | debugging. After system has booted up, it can be set | 205 | (e.g. thinkpad_acpi, sony_acpi, etc.) instead |
206 | via /sys/module/acpi/parameters/debug_layer. | 206 | of the ACPI video.ko driver. |
207 | CONFIG_ACPI_DEBUG must be enabled for this to produce any output. | 207 | |
208 | Available bits (add the numbers together) to enable debug output | 208 | acpi_display_output= [HW,ACPI] |
209 | for specific parts of the ACPI subsystem: | 209 | acpi_display_output=vendor |
210 | 0x01 utilities 0x02 hardware 0x04 events 0x08 tables | 210 | acpi_display_output=video |
211 | 0x10 namespace 0x20 parser 0x40 dispatcher | 211 | See above. |
212 | 0x80 executer 0x100 resources 0x200 acpica debugger | 212 | |
213 | 0x400 os services 0x800 acpica disassembler. | 213 | acpi.debug_layer= [HW,ACPI,ACPI_DEBUG] |
214 | The number can be in decimal or prefixed with 0x in hex. | 214 | acpi.debug_level= [HW,ACPI,ACPI_DEBUG] |
215 | Warning: Many of these options can produce a lot of | ||
216 | output and make your system unusable. Be very careful. | ||
217 | |||
218 | acpi.debug_level= [HW,ACPI] | ||
219 | Format: <int> | 215 | Format: <int> |
220 | Each bit of the <int> indicates an ACPI debug level, | 216 | CONFIG_ACPI_DEBUG must be enabled to produce any ACPI |
221 | which corresponds to the level in an ACPI_DEBUG_PRINT | 217 | debug output. Bits in debug_layer correspond to a |
222 | statement. After system has booted up, this mask | 218 | _COMPONENT in an ACPI source file, e.g., |
223 | can be set via /sys/module/acpi/parameters/debug_level. | 219 | #define _COMPONENT ACPI_PCI_COMPONENT |
224 | 220 | Bits in debug_level correspond to a level in | |
225 | CONFIG_ACPI_DEBUG must be enabled for this to produce | 221 | ACPI_DEBUG_PRINT statements, e.g., |
226 | any output. The number can be in decimal or prefixed | 222 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, ... |
227 | with 0x in hex. Some of these options produce so much | 223 | See Documentation/acpi/debug.txt for more information |
228 | output that the system is unusable. | 224 | about debug layers and levels. |
229 | 225 | ||
230 | The following global components are defined by the | 226 | Enable AML "Debug" output, i.e., stores to the Debug |
231 | ACPI CA: | 227 | object while interpreting AML: |
232 | 0x01 error | 228 | acpi.debug_layer=0xffffffff acpi.debug_level=0x2 |
233 | 0x02 warn | 229 | Enable PCI/PCI interrupt routing info messages: |
234 | 0x04 init | 230 | acpi.debug_layer=0x400000 acpi.debug_level=0x4 |
235 | 0x08 debug object | 231 | Enable all messages related to ACPI hardware: |
236 | 0x10 info | 232 | acpi.debug_layer=0x2 acpi.debug_level=0xffffffff |
237 | 0x20 init names | 233 | |
238 | 0x40 parse | 234 | Some values produce so much output that the system is |
239 | 0x80 load | 235 | unusable. The "log_buf_len" parameter may be useful |
240 | 0x100 dispatch | 236 | if you need to capture more output. |
241 | 0x200 execute | ||
242 | 0x400 names | ||
243 | 0x800 operation region | ||
244 | 0x1000 bfield | ||
245 | 0x2000 tables | ||
246 | 0x4000 values | ||
247 | 0x8000 objects | ||
248 | 0x10000 resources | ||
249 | 0x20000 user requests | ||
250 | 0x40000 package | ||
251 | The number can be in decimal or prefixed with 0x in hex. | ||
252 | Warning: Many of these options can produce a lot of | ||
253 | output and make your system unusable. Be very careful. | ||
254 | 237 | ||
255 | acpi.power_nocheck= [HW,ACPI] | 238 | acpi.power_nocheck= [HW,ACPI] |
256 | Format: 1/0 enable/disable the check of power state. | 239 | Format: 1/0 enable/disable the check of power state. |
@@ -311,7 +294,9 @@ and is between 256 and 4096 characters. It is defined in the file | |||
311 | Possible values are: | 294 | Possible values are: |
312 | isolate - enable device isolation (each device, as far | 295 | isolate - enable device isolation (each device, as far |
313 | as possible, will get its own protection | 296 | as possible, will get its own protection |
314 | domain) | 297 | domain) [default] |
298 | share - put every device behind one IOMMU into the | ||
299 | same protection domain | ||
315 | fullflush - enable flushing of IO/TLB entries when | 300 | fullflush - enable flushing of IO/TLB entries when |
316 | they are unmapped. Otherwise they are | 301 | they are unmapped. Otherwise they are |
317 | flushed before they will be reused, which | 302 | flushed before they will be reused, which |
@@ -646,7 +631,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
646 | 631 | ||
647 | digiepca= [HW,SERIAL] | 632 | digiepca= [HW,SERIAL] |
648 | See drivers/char/README.epca and | 633 | See drivers/char/README.epca and |
649 | Documentation/digiepca.txt. | 634 | Documentation/serial/digiepca.txt. |
650 | 635 | ||
651 | disable_mtrr_cleanup [X86] | 636 | disable_mtrr_cleanup [X86] |
652 | enable_mtrr_cleanup [X86] | 637 | enable_mtrr_cleanup [X86] |
@@ -757,7 +742,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
757 | See header of drivers/scsi/fdomain.c. | 742 | See header of drivers/scsi/fdomain.c. |
758 | 743 | ||
759 | floppy= [HW] | 744 | floppy= [HW] |
760 | See Documentation/floppy.txt. | 745 | See Documentation/blockdev/floppy.txt. |
761 | 746 | ||
762 | force_pal_cache_flush | 747 | force_pal_cache_flush |
763 | [IA-64] Avoid check_sal_cache_flush which may hang on | 748 | [IA-64] Avoid check_sal_cache_flush which may hang on |
@@ -995,13 +980,15 @@ and is between 256 and 4096 characters. It is defined in the file | |||
995 | Format: | 980 | Format: |
996 | <cpu number>,...,<cpu number> | 981 | <cpu number>,...,<cpu number> |
997 | or | 982 | or |
998 | <cpu number>-<cpu number> (must be a positive range in ascending order) | 983 | <cpu number>-<cpu number> |
984 | (must be a positive range in ascending order) | ||
999 | or a mixture | 985 | or a mixture |
1000 | <cpu number>,...,<cpu number>-<cpu number> | 986 | <cpu number>,...,<cpu number>-<cpu number> |
987 | |||
1001 | This option can be used to specify one or more CPUs | 988 | This option can be used to specify one or more CPUs |
1002 | to isolate from the general SMP balancing and scheduling | 989 | to isolate from the general SMP balancing and scheduling |
1003 | algorithms. The only way to move a process onto or off | 990 | algorithms. You can move a process onto or off an |
1004 | an "isolated" CPU is via the CPU affinity syscalls. | 991 | "isolated" CPU via the CPU affinity syscalls or cpuset. |
1005 | <cpu number> begins at 0 and the maximum value is | 992 | <cpu number> begins at 0 and the maximum value is |
1006 | "number of CPUs in system - 1". | 993 | "number of CPUs in system - 1". |
1007 | 994 | ||
@@ -1116,7 +1103,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1116 | the same attribute, the last one is used. | 1103 | the same attribute, the last one is used. |
1117 | 1104 | ||
1118 | load_ramdisk= [RAM] List of ramdisks to load from floppy | 1105 | load_ramdisk= [RAM] List of ramdisks to load from floppy |
1119 | See Documentation/ramdisk.txt. | 1106 | See Documentation/blockdev/ramdisk.txt. |
1120 | 1107 | ||
1121 | lockd.nlm_grace_period=P [NFS] Assign grace period. | 1108 | lockd.nlm_grace_period=P [NFS] Assign grace period. |
1122 | Format: <integer> | 1109 | Format: <integer> |
@@ -1208,8 +1195,8 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1208 | it is equivalent to "nosmp", which also disables | 1195 | it is equivalent to "nosmp", which also disables |
1209 | the IO APIC. | 1196 | the IO APIC. |
1210 | 1197 | ||
1211 | max_addr=[KMG] [KNL,BOOT,ia64] All physical memory greater than or | 1198 | max_addr=nn[KMG] [KNL,BOOT,ia64] All physical memory greater than |
1212 | equal to this physical address is ignored. | 1199 | or equal to this physical address is ignored. |
1213 | 1200 | ||
1214 | max_luns= [SCSI] Maximum number of LUNs to probe. | 1201 | max_luns= [SCSI] Maximum number of LUNs to probe. |
1215 | Should be between 1 and 2^32-1. | 1202 | Should be between 1 and 2^32-1. |
@@ -1222,7 +1209,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1222 | 1209 | ||
1223 | mce [X86-32] Machine Check Exception | 1210 | mce [X86-32] Machine Check Exception |
1224 | 1211 | ||
1225 | mce=option [X86-64] See Documentation/x86_64/boot-options.txt | 1212 | mce=option [X86-64] See Documentation/x86/x86_64/boot-options.txt |
1226 | 1213 | ||
1227 | md= [HW] RAID subsystems devices and level | 1214 | md= [HW] RAID subsystems devices and level |
1228 | See Documentation/md.txt. | 1215 | See Documentation/md.txt. |
@@ -1309,6 +1296,9 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1309 | 1296 | ||
1310 | mga= [HW,DRM] | 1297 | mga= [HW,DRM] |
1311 | 1298 | ||
1299 | min_addr=nn[KMG] [KNL,BOOT,ia64] All physical memory below this | ||
1300 | physical address is ignored. | ||
1301 | |||
1312 | mminit_loglevel= | 1302 | mminit_loglevel= |
1313 | [KNL] When CONFIG_DEBUG_MEMORY_INIT is set, this | 1303 | [KNL] When CONFIG_DEBUG_MEMORY_INIT is set, this |
1314 | parameter allows control of the logging verbosity for | 1304 | parameter allows control of the logging verbosity for |
@@ -1470,8 +1460,6 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1470 | Valid arguments: on, off | 1460 | Valid arguments: on, off |
1471 | Default: on | 1461 | Default: on |
1472 | 1462 | ||
1473 | noirqbalance [X86-32,SMP,KNL] Disable kernel irq balancing | ||
1474 | |||
1475 | noirqdebug [X86-32] Disables the code which attempts to detect and | 1463 | noirqdebug [X86-32] Disables the code which attempts to detect and |
1476 | disable unhandled interrupt sources. | 1464 | disable unhandled interrupt sources. |
1477 | 1465 | ||
@@ -1613,7 +1601,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1613 | 1601 | ||
1614 | pcd. [PARIDE] | 1602 | pcd. [PARIDE] |
1615 | See header of drivers/block/paride/pcd.c. | 1603 | See header of drivers/block/paride/pcd.c. |
1616 | See also Documentation/paride.txt. | 1604 | See also Documentation/blockdev/paride.txt. |
1617 | 1605 | ||
1618 | pci=option[,option...] [PCI] various PCI subsystem options: | 1606 | pci=option[,option...] [PCI] various PCI subsystem options: |
1619 | off [X86] don't probe for the PCI bus | 1607 | off [X86] don't probe for the PCI bus |
@@ -1714,7 +1702,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1714 | pcmv= [HW,PCMCIA] BadgePAD 4 | 1702 | pcmv= [HW,PCMCIA] BadgePAD 4 |
1715 | 1703 | ||
1716 | pd. [PARIDE] | 1704 | pd. [PARIDE] |
1717 | See Documentation/paride.txt. | 1705 | See Documentation/blockdev/paride.txt. |
1718 | 1706 | ||
1719 | pdcchassis= [PARISC,HW] Disable/Enable PDC Chassis Status codes at | 1707 | pdcchassis= [PARISC,HW] Disable/Enable PDC Chassis Status codes at |
1720 | boot time. | 1708 | boot time. |
@@ -1722,13 +1710,13 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1722 | See arch/parisc/kernel/pdc_chassis.c | 1710 | See arch/parisc/kernel/pdc_chassis.c |
1723 | 1711 | ||
1724 | pf. [PARIDE] | 1712 | pf. [PARIDE] |
1725 | See Documentation/paride.txt. | 1713 | See Documentation/blockdev/paride.txt. |
1726 | 1714 | ||
1727 | pg. [PARIDE] | 1715 | pg. [PARIDE] |
1728 | See Documentation/paride.txt. | 1716 | See Documentation/blockdev/paride.txt. |
1729 | 1717 | ||
1730 | pirq= [SMP,APIC] Manual mp-table setup | 1718 | pirq= [SMP,APIC] Manual mp-table setup |
1731 | See Documentation/i386/IO-APIC.txt. | 1719 | See Documentation/x86/i386/IO-APIC.txt. |
1732 | 1720 | ||
1733 | plip= [PPT,NET] Parallel port network link | 1721 | plip= [PPT,NET] Parallel port network link |
1734 | Format: { parport<nr> | timid | 0 } | 1722 | Format: { parport<nr> | timid | 0 } |
@@ -1795,7 +1783,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1795 | 1783 | ||
1796 | prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk | 1784 | prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk |
1797 | before loading. | 1785 | before loading. |
1798 | See Documentation/ramdisk.txt. | 1786 | See Documentation/blockdev/ramdisk.txt. |
1799 | 1787 | ||
1800 | psmouse.proto= [HW,MOUSE] Highest PS2 mouse protocol extension to | 1788 | psmouse.proto= [HW,MOUSE] Highest PS2 mouse protocol extension to |
1801 | probe for; one of (bare|imps|exps|lifebook|any). | 1789 | probe for; one of (bare|imps|exps|lifebook|any). |
@@ -1815,7 +1803,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1815 | <io>,<mss_io>,<mss_irq>,<mss_dma>,<mpu_io>,<mpu_irq> | 1803 | <io>,<mss_io>,<mss_irq>,<mss_dma>,<mpu_io>,<mpu_irq> |
1816 | 1804 | ||
1817 | pt. [PARIDE] | 1805 | pt. [PARIDE] |
1818 | See Documentation/paride.txt. | 1806 | See Documentation/blockdev/paride.txt. |
1819 | 1807 | ||
1820 | pty.legacy_count= | 1808 | pty.legacy_count= |
1821 | [KNL] Number of legacy pty's. Overwrites compiled-in | 1809 | [KNL] Number of legacy pty's. Overwrites compiled-in |
@@ -1829,10 +1817,10 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1829 | See Documentation/md.txt. | 1817 | See Documentation/md.txt. |
1830 | 1818 | ||
1831 | ramdisk_blocksize= [RAM] | 1819 | ramdisk_blocksize= [RAM] |
1832 | See Documentation/ramdisk.txt. | 1820 | See Documentation/blockdev/ramdisk.txt. |
1833 | 1821 | ||
1834 | ramdisk_size= [RAM] Sizes of RAM disks in kilobytes | 1822 | ramdisk_size= [RAM] Sizes of RAM disks in kilobytes |
1835 | See Documentation/ramdisk.txt. | 1823 | See Documentation/blockdev/ramdisk.txt. |
1836 | 1824 | ||
1837 | rcupdate.blimit= [KNL,BOOT] | 1825 | rcupdate.blimit= [KNL,BOOT] |
1838 | Set maximum number of finished RCU callbacks to process | 1826 | Set maximum number of finished RCU callbacks to process |
@@ -2164,7 +2152,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
2164 | See Documentation/sonypi.txt | 2152 | See Documentation/sonypi.txt |
2165 | 2153 | ||
2166 | specialix= [HW,SERIAL] Specialix multi-serial port adapter | 2154 | specialix= [HW,SERIAL] Specialix multi-serial port adapter |
2167 | See Documentation/specialix.txt. | 2155 | See Documentation/serial/specialix.txt. |
2168 | 2156 | ||
2169 | spia_io_base= [HW,MTD] | 2157 | spia_io_base= [HW,MTD] |
2170 | spia_fio_base= | 2158 | spia_fio_base= |
@@ -2343,7 +2331,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
2343 | See Documentation/fb/modedb.txt. | 2331 | See Documentation/fb/modedb.txt. |
2344 | 2332 | ||
2345 | vga= [BOOT,X86-32] Select a particular video mode | 2333 | vga= [BOOT,X86-32] Select a particular video mode |
2346 | See Documentation/i386/boot.txt and | 2334 | See Documentation/x86/i386/boot.txt and |
2347 | Documentation/svga.txt. | 2335 | Documentation/svga.txt. |
2348 | Use vga=ask for menu. | 2336 | Use vga=ask for menu. |
2349 | This is actually a boot loader parameter; the value is | 2337 | This is actually a boot loader parameter; the value is |