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-rw-r--r--Documentation/kernel-parameters.txt155
1 files changed, 87 insertions, 68 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index c86c07459712..d5418d528910 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -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 acpi_backlight=vendor
203 acpi_backlight=video
204 If set to vendor, prefer vendor specific driver
205 (e.g. thinkpad_acpi, sony_acpi, etc.) instead
206 of the ACPI video.ko driver.
207
208 acpi_display_output= [HW,ACPI]
209 acpi_display_output=vendor
210 acpi_display_output=video
211 See above.
212
213 acpi.debug_layer= [HW,ACPI,ACPI_DEBUG]
214 acpi.debug_level= [HW,ACPI,ACPI_DEBUG]
202 Format: <int> 215 Format: <int>
203 Each bit of the <int> indicates an ACPI debug layer, 216 CONFIG_ACPI_DEBUG must be enabled to produce any ACPI
204 1: enable, 0: disable. It is useful for boot time 217 debug output. Bits in debug_layer correspond to a
205 debugging. After system has booted up, it can be set 218 _COMPONENT in an ACPI source file, e.g.,
206 via /sys/module/acpi/parameters/debug_layer. 219 #define _COMPONENT ACPI_PCI_COMPONENT
207 CONFIG_ACPI_DEBUG must be enabled for this to produce any output. 220 Bits in debug_level correspond to a level in
208 Available bits (add the numbers together) to enable debug output 221 ACPI_DEBUG_PRINT statements, e.g.,
209 for specific parts of the ACPI subsystem: 222 ACPI_DEBUG_PRINT((ACPI_DB_INFO, ...
210 0x01 utilities 0x02 hardware 0x04 events 0x08 tables 223 See Documentation/acpi/debug.txt for more information
211 0x10 namespace 0x20 parser 0x40 dispatcher 224 about debug layers and levels.
212 0x80 executer 0x100 resources 0x200 acpica debugger 225
213 0x400 os services 0x800 acpica disassembler. 226 Enable AML "Debug" output, i.e., stores to the Debug
214 The number can be in decimal or prefixed with 0x in hex. 227 object while interpreting AML:
215 Warning: Many of these options can produce a lot of 228 acpi.debug_layer=0xffffffff acpi.debug_level=0x2
216 output and make your system unusable. Be very careful. 229 Enable PCI/PCI interrupt routing info messages:
217 230 acpi.debug_layer=0x400000 acpi.debug_level=0x4
218 acpi.debug_level= [HW,ACPI] 231 Enable all messages related to ACPI hardware:
219 Format: <int> 232 acpi.debug_layer=0x2 acpi.debug_level=0xffffffff
220 Each bit of the <int> indicates an ACPI debug level, 233
221 which corresponds to the level in an ACPI_DEBUG_PRINT 234 Some values produce so much output that the system is
222 statement. After system has booted up, this mask 235 unusable. The "log_buf_len" parameter may be useful
223 can be set via /sys/module/acpi/parameters/debug_level. 236 if you need to capture more output.
224
225 CONFIG_ACPI_DEBUG must be enabled for this to produce
226 any output. The number can be in decimal or prefixed
227 with 0x in hex. Some of these options produce so much
228 output that the system is unusable.
229
230 The following global components are defined by the
231 ACPI CA:
232 0x01 error
233 0x02 warn
234 0x04 init
235 0x08 debug object
236 0x10 info
237 0x20 init names
238 0x40 parse
239 0x80 load
240 0x100 dispatch
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
@@ -1118,7 +1103,7 @@ and is between 256 and 4096 characters. It is defined in the file
1118 the same attribute, the last one is used. 1103 the same attribute, the last one is used.
1119 1104
1120 load_ramdisk= [RAM] List of ramdisks to load from floppy 1105 load_ramdisk= [RAM] List of ramdisks to load from floppy
1121 See Documentation/ramdisk.txt. 1106 See Documentation/blockdev/ramdisk.txt.
1122 1107
1123 lockd.nlm_grace_period=P [NFS] Assign grace period. 1108 lockd.nlm_grace_period=P [NFS] Assign grace period.
1124 Format: <integer> 1109 Format: <integer>
@@ -1210,8 +1195,8 @@ and is between 256 and 4096 characters. It is defined in the file
1210 it is equivalent to "nosmp", which also disables 1195 it is equivalent to "nosmp", which also disables
1211 the IO APIC. 1196 the IO APIC.
1212 1197
1213 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
1214 equal to this physical address is ignored. 1199 or equal to this physical address is ignored.
1215 1200
1216 max_luns= [SCSI] Maximum number of LUNs to probe. 1201 max_luns= [SCSI] Maximum number of LUNs to probe.
1217 Should be between 1 and 2^32-1. 1202 Should be between 1 and 2^32-1.
@@ -1311,6 +1296,9 @@ and is between 256 and 4096 characters. It is defined in the file
1311 1296
1312 mga= [HW,DRM] 1297 mga= [HW,DRM]
1313 1298
1299 min_addr=nn[KMG] [KNL,BOOT,ia64] All physical memory below this
1300 physical address is ignored.
1301
1314 mminit_loglevel= 1302 mminit_loglevel=
1315 [KNL] When CONFIG_DEBUG_MEMORY_INIT is set, this 1303 [KNL] When CONFIG_DEBUG_MEMORY_INIT is set, this
1316 parameter allows control of the logging verbosity for 1304 parameter allows control of the logging verbosity for
@@ -1405,7 +1393,20 @@ and is between 256 and 4096 characters. It is defined in the file
1405 when a NMI is triggered. 1393 when a NMI is triggered.
1406 Format: [state][,regs][,debounce][,die] 1394 Format: [state][,regs][,debounce][,die]
1407 1395
1408 nmi_watchdog= [KNL,BUGS=X86-32] Debugging features for SMP kernels 1396 nmi_watchdog= [KNL,BUGS=X86-32,X86-64] Debugging features for SMP kernels
1397 Format: [panic,][num]
1398 Valid num: 0,1,2
1399 0 - turn nmi_watchdog off
1400 1 - use the IO-APIC timer for the NMI watchdog
1401 2 - use the local APIC for the NMI watchdog using
1402 a performance counter. Note: This will use one performance
1403 counter and the local APIC's performance vector.
1404 When panic is specified panic when an NMI watchdog timeout occurs.
1405 This is useful when you use a panic=... timeout and need the box
1406 quickly up again.
1407 Instead of 1 and 2 it is possible to use the following
1408 symbolic names: lapic and ioapic
1409 Example: nmi_watchdog=2 or nmi_watchdog=panic,lapic
1409 1410
1410 no387 [BUGS=X86-32] Tells the kernel to use the 387 maths 1411 no387 [BUGS=X86-32] Tells the kernel to use the 387 maths
1411 emulation library even if a 387 maths coprocessor 1412 emulation library even if a 387 maths coprocessor
@@ -1613,7 +1614,7 @@ and is between 256 and 4096 characters. It is defined in the file
1613 1614
1614 pcd. [PARIDE] 1615 pcd. [PARIDE]
1615 See header of drivers/block/paride/pcd.c. 1616 See header of drivers/block/paride/pcd.c.
1616 See also Documentation/paride.txt. 1617 See also Documentation/blockdev/paride.txt.
1617 1618
1618 pci=option[,option...] [PCI] various PCI subsystem options: 1619 pci=option[,option...] [PCI] various PCI subsystem options:
1619 off [X86] don't probe for the PCI bus 1620 off [X86] don't probe for the PCI bus
@@ -1638,6 +1639,17 @@ and is between 256 and 4096 characters. It is defined in the file
1638 nomsi [MSI] If the PCI_MSI kernel config parameter is 1639 nomsi [MSI] If the PCI_MSI kernel config parameter is
1639 enabled, this kernel boot option can be used to 1640 enabled, this kernel boot option can be used to
1640 disable the use of MSI interrupts system-wide. 1641 disable the use of MSI interrupts system-wide.
1642 noioapicquirk [APIC] Disable all boot interrupt quirks.
1643 Safety option to keep boot IRQs enabled. This
1644 should never be necessary.
1645 ioapicreroute [APIC] Enable rerouting of boot IRQs to the
1646 primary IO-APIC for bridges that cannot disable
1647 boot IRQs. This fixes a source of spurious IRQs
1648 when the system masks IRQs.
1649 noioapicreroute [APIC] Disable workaround that uses the
1650 boot IRQ equivalent of an IRQ that connects to
1651 a chipset where boot IRQs cannot be disabled.
1652 The opposite of ioapicreroute.
1641 biosirq [X86-32] Use PCI BIOS calls to get the interrupt 1653 biosirq [X86-32] Use PCI BIOS calls to get the interrupt
1642 routing table. These calls are known to be buggy 1654 routing table. These calls are known to be buggy
1643 on several machines and they hang the machine 1655 on several machines and they hang the machine
@@ -1714,7 +1726,7 @@ and is between 256 and 4096 characters. It is defined in the file
1714 pcmv= [HW,PCMCIA] BadgePAD 4 1726 pcmv= [HW,PCMCIA] BadgePAD 4
1715 1727
1716 pd. [PARIDE] 1728 pd. [PARIDE]
1717 See Documentation/paride.txt. 1729 See Documentation/blockdev/paride.txt.
1718 1730
1719 pdcchassis= [PARISC,HW] Disable/Enable PDC Chassis Status codes at 1731 pdcchassis= [PARISC,HW] Disable/Enable PDC Chassis Status codes at
1720 boot time. 1732 boot time.
@@ -1722,10 +1734,10 @@ and is between 256 and 4096 characters. It is defined in the file
1722 See arch/parisc/kernel/pdc_chassis.c 1734 See arch/parisc/kernel/pdc_chassis.c
1723 1735
1724 pf. [PARIDE] 1736 pf. [PARIDE]
1725 See Documentation/paride.txt. 1737 See Documentation/blockdev/paride.txt.
1726 1738
1727 pg. [PARIDE] 1739 pg. [PARIDE]
1728 See Documentation/paride.txt. 1740 See Documentation/blockdev/paride.txt.
1729 1741
1730 pirq= [SMP,APIC] Manual mp-table setup 1742 pirq= [SMP,APIC] Manual mp-table setup
1731 See Documentation/x86/i386/IO-APIC.txt. 1743 See Documentation/x86/i386/IO-APIC.txt.
@@ -1795,7 +1807,7 @@ and is between 256 and 4096 characters. It is defined in the file
1795 1807
1796 prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk 1808 prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk
1797 before loading. 1809 before loading.
1798 See Documentation/ramdisk.txt. 1810 See Documentation/blockdev/ramdisk.txt.
1799 1811
1800 psmouse.proto= [HW,MOUSE] Highest PS2 mouse protocol extension to 1812 psmouse.proto= [HW,MOUSE] Highest PS2 mouse protocol extension to
1801 probe for; one of (bare|imps|exps|lifebook|any). 1813 probe for; one of (bare|imps|exps|lifebook|any).
@@ -1815,7 +1827,7 @@ 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> 1827 <io>,<mss_io>,<mss_irq>,<mss_dma>,<mpu_io>,<mpu_irq>
1816 1828
1817 pt. [PARIDE] 1829 pt. [PARIDE]
1818 See Documentation/paride.txt. 1830 See Documentation/blockdev/paride.txt.
1819 1831
1820 pty.legacy_count= 1832 pty.legacy_count=
1821 [KNL] Number of legacy pty's. Overwrites compiled-in 1833 [KNL] Number of legacy pty's. Overwrites compiled-in
@@ -1829,10 +1841,10 @@ and is between 256 and 4096 characters. It is defined in the file
1829 See Documentation/md.txt. 1841 See Documentation/md.txt.
1830 1842
1831 ramdisk_blocksize= [RAM] 1843 ramdisk_blocksize= [RAM]
1832 See Documentation/ramdisk.txt. 1844 See Documentation/blockdev/ramdisk.txt.
1833 1845
1834 ramdisk_size= [RAM] Sizes of RAM disks in kilobytes 1846 ramdisk_size= [RAM] Sizes of RAM disks in kilobytes
1835 See Documentation/ramdisk.txt. 1847 See Documentation/blockdev/ramdisk.txt.
1836 1848
1837 rcupdate.blimit= [KNL,BOOT] 1849 rcupdate.blimit= [KNL,BOOT]
1838 Set maximum number of finished RCU callbacks to process 1850 Set maximum number of finished RCU callbacks to process
@@ -2164,7 +2176,7 @@ and is between 256 and 4096 characters. It is defined in the file
2164 See Documentation/sonypi.txt 2176 See Documentation/sonypi.txt
2165 2177
2166 specialix= [HW,SERIAL] Specialix multi-serial port adapter 2178 specialix= [HW,SERIAL] Specialix multi-serial port adapter
2167 See Documentation/specialix.txt. 2179 See Documentation/serial/specialix.txt.
2168 2180
2169 spia_io_base= [HW,MTD] 2181 spia_io_base= [HW,MTD]
2170 spia_fio_base= 2182 spia_fio_base=
@@ -2267,6 +2279,13 @@ and is between 256 and 4096 characters. It is defined in the file
2267 Format: 2279 Format:
2268 <io>,<irq>,<dma>,<dma2>,<sb_io>,<sb_irq>,<sb_dma>,<mpu_io>,<mpu_irq> 2280 <io>,<irq>,<dma>,<dma2>,<sb_io>,<sb_irq>,<sb_dma>,<mpu_io>,<mpu_irq>
2269 2281
2282 tsc= Disable clocksource-must-verify flag for TSC.
2283 Format: <string>
2284 [x86] reliable: mark tsc clocksource as reliable, this
2285 disables clocksource verification at runtime.
2286 Used to enable high-resolution timer mode on older
2287 hardware, and in virtualized environment.
2288
2270 turbografx.map[2|3]= [HW,JOY] 2289 turbografx.map[2|3]= [HW,JOY]
2271 TurboGraFX parallel port interface 2290 TurboGraFX parallel port interface
2272 Format: 2291 Format: