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-rw-r--r--Documentation/kernel-parameters.txt160
1 files changed, 149 insertions, 11 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index ad3800630772..f45d0d8e71d8 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -48,6 +48,7 @@ parameter is applicable:
48 EFI EFI Partitioning (GPT) is enabled 48 EFI EFI Partitioning (GPT) is enabled
49 EIDE EIDE/ATAPI support is enabled. 49 EIDE EIDE/ATAPI support is enabled.
50 FB The frame buffer device is enabled. 50 FB The frame buffer device is enabled.
51 GCOV GCOV profiling is enabled.
51 HW Appropriate hardware is enabled. 52 HW Appropriate hardware is enabled.
52 IA-64 IA-64 architecture is enabled. 53 IA-64 IA-64 architecture is enabled.
53 IMA Integrity measurement architecture is enabled. 54 IMA Integrity measurement architecture is enabled.
@@ -56,6 +57,7 @@ parameter is applicable:
56 ISAPNP ISA PnP code is enabled. 57 ISAPNP ISA PnP code is enabled.
57 ISDN Appropriate ISDN support is enabled. 58 ISDN Appropriate ISDN support is enabled.
58 JOY Appropriate joystick support is enabled. 59 JOY Appropriate joystick support is enabled.
60 KVM Kernel Virtual Machine support is enabled.
59 LIBATA Libata driver is enabled 61 LIBATA Libata driver is enabled
60 LP Printer support is enabled. 62 LP Printer support is enabled.
61 LOOP Loopback device support is enabled. 63 LOOP Loopback device support is enabled.
@@ -228,14 +230,6 @@ and is between 256 and 4096 characters. It is defined in the file
228 to assume that this machine's pmtimer latches its value 230 to assume that this machine's pmtimer latches its value
229 and always returns good values. 231 and always returns good values.
230 232
231 acpi.power_nocheck= [HW,ACPI]
232 Format: 1/0 enable/disable the check of power state.
233 On some bogus BIOS the _PSC object/_STA object of
234 power resource can't return the correct device power
235 state. In such case it is unneccessary to check its
236 power state again in power transition.
237 1 : disable the power state check
238
239 acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode 233 acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
240 Format: { level | edge | high | low } 234 Format: { level | edge | high | low }
241 235
@@ -546,6 +540,10 @@ and is between 256 and 4096 characters. It is defined in the file
546 console=brl,ttyS0 540 console=brl,ttyS0
547 For now, only VisioBraille is supported. 541 For now, only VisioBraille is supported.
548 542
543 consoleblank= [KNL] The console blank (screen saver) timeout in
544 seconds. Defaults to 10*60 = 10mins. A value of 0
545 disables the blank timer.
546
549 coredump_filter= 547 coredump_filter=
550 [KNL] Change the default value for 548 [KNL] Change the default value for
551 /proc/<pid>/coredump_filter. 549 /proc/<pid>/coredump_filter.
@@ -792,6 +790,12 @@ and is between 256 and 4096 characters. It is defined in the file
792 Format: off | on 790 Format: off | on
793 default: on 791 default: on
794 792
793 gcov_persist= [GCOV] When non-zero (default), profiling data for
794 kernel modules is saved and remains accessible via
795 debugfs, even when the module is unloaded/reloaded.
796 When zero, profiling data is discarded and associated
797 debugfs files are removed at module unload time.
798
795 gdth= [HW,SCSI] 799 gdth= [HW,SCSI]
796 See header of drivers/scsi/gdth.c. 800 See header of drivers/scsi/gdth.c.
797 801
@@ -995,6 +999,7 @@ and is between 256 and 4096 characters. It is defined in the file
995 nomerge 999 nomerge
996 forcesac 1000 forcesac
997 soft 1001 soft
1002 pt [x86, IA64]
998 1003
999 io7= [HW] IO7 for Marvel based alpha systems 1004 io7= [HW] IO7 for Marvel based alpha systems
1000 See comment before marvel_specify_io7 in 1005 See comment before marvel_specify_io7 in
@@ -1094,6 +1099,44 @@ and is between 256 and 4096 characters. It is defined in the file
1094 kstack=N [X86] Print N words from the kernel stack 1099 kstack=N [X86] Print N words from the kernel stack
1095 in oops dumps. 1100 in oops dumps.
1096 1101
1102 kvm.ignore_msrs=[KVM] Ignore guest accesses to unhandled MSRs.
1103 Default is 0 (don't ignore, but inject #GP)
1104
1105 kvm.oos_shadow= [KVM] Disable out-of-sync shadow paging.
1106 Default is 1 (enabled)
1107
1108 kvm-amd.nested= [KVM,AMD] Allow nested virtualization in KVM/SVM.
1109 Default is 0 (off)
1110
1111 kvm-amd.npt= [KVM,AMD] Disable nested paging (virtualized MMU)
1112 for all guests.
1113 Default is 1 (enabled) if in 64bit or 32bit-PAE mode
1114
1115 kvm-intel.bypass_guest_pf=
1116 [KVM,Intel] Disables bypassing of guest page faults
1117 on Intel chips. Default is 1 (enabled)
1118
1119 kvm-intel.ept= [KVM,Intel] Disable extended page tables
1120 (virtualized MMU) support on capable Intel chips.
1121 Default is 1 (enabled)
1122
1123 kvm-intel.emulate_invalid_guest_state=
1124 [KVM,Intel] Enable emulation of invalid guest states
1125 Default is 0 (disabled)
1126
1127 kvm-intel.flexpriority=
1128 [KVM,Intel] Disable FlexPriority feature (TPR shadow).
1129 Default is 1 (enabled)
1130
1131 kvm-intel.unrestricted_guest=
1132 [KVM,Intel] Disable unrestricted guest feature
1133 (virtualized real and unpaged mode) on capable
1134 Intel chips. Default is 1 (enabled)
1135
1136 kvm-intel.vpid= [KVM,Intel] Disable Virtual Processor Identification
1137 feature (tagged TLBs) on capable Intel chips.
1138 Default is 1 (enabled)
1139
1097 l2cr= [PPC] 1140 l2cr= [PPC]
1098 1141
1099 l3cr= [PPC] 1142 l3cr= [PPC]
@@ -1111,6 +1154,10 @@ and is between 256 and 4096 characters. It is defined in the file
1111 libata.dma=4 Compact Flash DMA only 1154 libata.dma=4 Compact Flash DMA only
1112 Combinations also work, so libata.dma=3 enables DMA 1155 Combinations also work, so libata.dma=3 enables DMA
1113 for disks and CDROMs, but not CFs. 1156 for disks and CDROMs, but not CFs.
1157
1158 libata.ignore_hpa= [LIBATA] Ignore HPA limit
1159 libata.ignore_hpa=0 keep BIOS limits (default)
1160 libata.ignore_hpa=1 ignore limits, using full disk
1114 1161
1115 libata.noacpi [LIBATA] Disables use of ACPI in libata suspend/resume 1162 libata.noacpi [LIBATA] Disables use of ACPI in libata suspend/resume
1116 when set. 1163 when set.
@@ -1239,6 +1286,10 @@ and is between 256 and 4096 characters. It is defined in the file
1239 (machvec) in a generic kernel. 1286 (machvec) in a generic kernel.
1240 Example: machvec=hpzx1_swiotlb 1287 Example: machvec=hpzx1_swiotlb
1241 1288
1289 machtype= [Loongson] Share the same kernel image file between different
1290 yeeloong laptop.
1291 Example: machtype=lemote-yeeloong-2f-7inch
1292
1242 max_addr=nn[KMG] [KNL,BOOT,ia64] All physical memory greater 1293 max_addr=nn[KMG] [KNL,BOOT,ia64] All physical memory greater
1243 than or equal to this physical address is ignored. 1294 than or equal to this physical address is ignored.
1244 1295
@@ -1358,6 +1409,27 @@ and is between 256 and 4096 characters. It is defined in the file
1358 min_addr=nn[KMG] [KNL,BOOT,ia64] All physical memory below this 1409 min_addr=nn[KMG] [KNL,BOOT,ia64] All physical memory below this
1359 physical address is ignored. 1410 physical address is ignored.
1360 1411
1412 mini2440= [ARM,HW,KNL]
1413 Format:[0..2][b][c][t]
1414 Default: "0tb"
1415 MINI2440 configuration specification:
1416 0 - The attached screen is the 3.5" TFT
1417 1 - The attached screen is the 7" TFT
1418 2 - The VGA Shield is attached (1024x768)
1419 Leaving out the screen size parameter will not load
1420 the TFT driver, and the framebuffer will be left
1421 unconfigured.
1422 b - Enable backlight. The TFT backlight pin will be
1423 linked to the kernel VESA blanking code and a GPIO
1424 LED. This parameter is not necessary when using the
1425 VGA shield.
1426 c - Enable the s3c camera interface.
1427 t - Reserved for enabling touchscreen support. The
1428 touchscreen support is not enabled in the mainstream
1429 kernel as of 2.6.30, a preliminary port can be found
1430 in the "bleeding edge" mini2440 support kernel at
1431 http://repo.or.cz/w/linux-2.6/mini2440.git
1432
1361 mminit_loglevel= 1433 mminit_loglevel=
1362 [KNL] When CONFIG_DEBUG_MEMORY_INIT is set, this 1434 [KNL] When CONFIG_DEBUG_MEMORY_INIT is set, this
1363 parameter allows control of the logging verbosity for 1435 parameter allows control of the logging verbosity for
@@ -1399,6 +1471,16 @@ and is between 256 and 4096 characters. It is defined in the file
1399 mtdparts= [MTD] 1471 mtdparts= [MTD]
1400 See drivers/mtd/cmdlinepart.c. 1472 See drivers/mtd/cmdlinepart.c.
1401 1473
1474 onenand.bdry= [HW,MTD] Flex-OneNAND Boundary Configuration
1475
1476 Format: [die0_boundary][,die0_lock][,die1_boundary][,die1_lock]
1477
1478 boundary - index of last SLC block on Flex-OneNAND.
1479 The remaining blocks are configured as MLC blocks.
1480 lock - Configure if Flex-OneNAND boundary should be locked.
1481 Once locked, the boundary cannot be changed.
1482 1 indicates lock status, 0 indicates unlock status.
1483
1402 mtdset= [ARM] 1484 mtdset= [ARM]
1403 ARM/S3C2412 JIVE boot control 1485 ARM/S3C2412 JIVE boot control
1404 1486
@@ -1464,6 +1546,14 @@ and is between 256 and 4096 characters. It is defined in the file
1464 [NFS] set the TCP port on which the NFSv4 callback 1546 [NFS] set the TCP port on which the NFSv4 callback
1465 channel should listen. 1547 channel should listen.
1466 1548
1549 nfs.cache_getent=
1550 [NFS] sets the pathname to the program which is used
1551 to update the NFS client cache entries.
1552
1553 nfs.cache_getent_timeout=
1554 [NFS] sets the timeout after which an attempt to
1555 update a cache entry is deemed to have failed.
1556
1467 nfs.idmap_cache_timeout= 1557 nfs.idmap_cache_timeout=
1468 [NFS] set the maximum lifetime for idmapper cache 1558 [NFS] set the maximum lifetime for idmapper cache
1469 entries. 1559 entries.
@@ -1496,6 +1586,11 @@ and is between 256 and 4096 characters. It is defined in the file
1496 symbolic names: lapic and ioapic 1586 symbolic names: lapic and ioapic
1497 Example: nmi_watchdog=2 or nmi_watchdog=panic,lapic 1587 Example: nmi_watchdog=2 or nmi_watchdog=panic,lapic
1498 1588
1589 netpoll.carrier_timeout=
1590 [NET] Specifies amount of time (in seconds) that
1591 netpoll should wait for a carrier. By default netpoll
1592 waits 4 seconds.
1593
1499 no387 [BUGS=X86-32] Tells the kernel to use the 387 maths 1594 no387 [BUGS=X86-32] Tells the kernel to use the 387 maths
1500 emulation library even if a 387 maths coprocessor 1595 emulation library even if a 387 maths coprocessor
1501 is present. 1596 is present.
@@ -1685,8 +1780,8 @@ and is between 256 and 4096 characters. It is defined in the file
1685 oprofile.cpu_type= Force an oprofile cpu type 1780 oprofile.cpu_type= Force an oprofile cpu type
1686 This might be useful if you have an older oprofile 1781 This might be useful if you have an older oprofile
1687 userland or if you want common events. 1782 userland or if you want common events.
1688 Format: { archperfmon } 1783 Format: { arch_perfmon }
1689 archperfmon: [X86] Force use of architectural 1784 arch_perfmon: [X86] Force use of architectural
1690 perfmon on Intel CPUs instead of the 1785 perfmon on Intel CPUs instead of the
1691 CPU specific event set. 1786 CPU specific event set.
1692 1787
@@ -1765,6 +1860,9 @@ and is between 256 and 4096 characters. It is defined in the file
1765 root domains (aka PCI segments, in ACPI-speak). 1860 root domains (aka PCI segments, in ACPI-speak).
1766 nommconf [X86] Disable use of MMCONFIG for PCI 1861 nommconf [X86] Disable use of MMCONFIG for PCI
1767 Configuration 1862 Configuration
1863 check_enable_amd_mmconf [X86] check for and enable
1864 properly configured MMIO access to PCI
1865 config space on AMD family 10h CPU
1768 nomsi [MSI] If the PCI_MSI kernel config parameter is 1866 nomsi [MSI] If the PCI_MSI kernel config parameter is
1769 enabled, this kernel boot option can be used to 1867 enabled, this kernel boot option can be used to
1770 disable the use of MSI interrupts system-wide. 1868 disable the use of MSI interrupts system-wide.
@@ -1854,6 +1952,12 @@ and is between 256 and 4096 characters. It is defined in the file
1854 PAGE_SIZE is used as alignment. 1952 PAGE_SIZE is used as alignment.
1855 PCI-PCI bridge can be specified, if resource 1953 PCI-PCI bridge can be specified, if resource
1856 windows need to be expanded. 1954 windows need to be expanded.
1955 ecrc= Enable/disable PCIe ECRC (transaction layer
1956 end-to-end CRC checking).
1957 bios: Use BIOS/firmware settings. This is the
1958 the default.
1959 off: Turn ECRC off
1960 on: Turn ECRC on.
1857 1961
1858 pcie_aspm= [PCIE] Forcibly enable or disable PCIe Active State Power 1962 pcie_aspm= [PCIE] Forcibly enable or disable PCIe Active State Power
1859 Management. 1963 Management.
@@ -1871,6 +1975,13 @@ and is between 256 and 4096 characters. It is defined in the file
1871 Format: { 0 | 1 } 1975 Format: { 0 | 1 }
1872 See arch/parisc/kernel/pdc_chassis.c 1976 See arch/parisc/kernel/pdc_chassis.c
1873 1977
1978 percpu_alloc= Select which percpu first chunk allocator to use.
1979 Currently supported values are "embed" and "page".
1980 Archs may support subset or none of the selections.
1981 See comments in mm/percpu.c for details on each
1982 allocator. This parameter is primarily for debugging
1983 and performance comparison.
1984
1874 pf. [PARIDE] 1985 pf. [PARIDE]
1875 See Documentation/blockdev/paride.txt. 1986 See Documentation/blockdev/paride.txt.
1876 1987
@@ -2341,6 +2452,18 @@ and is between 256 and 4096 characters. It is defined in the file
2341 stifb= [HW] 2452 stifb= [HW]
2342 Format: bpp:<bpp1>[:<bpp2>[:<bpp3>...]] 2453 Format: bpp:<bpp1>[:<bpp2>[:<bpp3>...]]
2343 2454
2455 sunrpc.min_resvport=
2456 sunrpc.max_resvport=
2457 [NFS,SUNRPC]
2458 SunRPC servers often require that client requests
2459 originate from a privileged port (i.e. a port in the
2460 range 0 < portnr < 1024).
2461 An administrator who wishes to reserve some of these
2462 ports for other uses may adjust the range that the
2463 kernel's sunrpc client considers to be privileged
2464 using these two parameters to set the minimum and
2465 maximum port values.
2466
2344 sunrpc.pool_mode= 2467 sunrpc.pool_mode=
2345 [NFS] 2468 [NFS]
2346 Control how the NFS server code allocates CPUs to 2469 Control how the NFS server code allocates CPUs to
@@ -2357,6 +2480,15 @@ and is between 256 and 4096 characters. It is defined in the file
2357 pernode one pool for each NUMA node (equivalent 2480 pernode one pool for each NUMA node (equivalent
2358 to global on non-NUMA machines) 2481 to global on non-NUMA machines)
2359 2482
2483 sunrpc.tcp_slot_table_entries=
2484 sunrpc.udp_slot_table_entries=
2485 [NFS,SUNRPC]
2486 Sets the upper limit on the number of simultaneous
2487 RPC calls that can be sent from the client to a
2488 server. Increasing these values may allow you to
2489 improve throughput, but will also increase the
2490 amount of memory reserved for use by the client.
2491
2360 swiotlb= [IA-64] Number of I/O TLB slabs 2492 swiotlb= [IA-64] Number of I/O TLB slabs
2361 2493
2362 switches= [HW,M68k] 2494 switches= [HW,M68k]
@@ -2423,7 +2555,13 @@ and is between 256 and 4096 characters. It is defined in the file
2423 2555
2424 tp720= [HW,PS2] 2556 tp720= [HW,PS2]
2425 2557
2426 trace_buf_size=nn[KMG] [ftrace] will set tracing buffer size. 2558 trace_buf_size=nn[KMG]
2559 [FTRACE] will set tracing buffer size.
2560
2561 trace_event=[event-list]
2562 [FTRACE] Set and start specified trace events in order
2563 to facilitate early boot debugging.
2564 See also Documentation/trace/events.txt
2427 2565
2428 trix= [HW,OSS] MediaTrix AudioTrix Pro 2566 trix= [HW,OSS] MediaTrix AudioTrix Pro
2429 Format: 2567 Format: