diff options
Diffstat (limited to 'Documentation/admin-guide/kernel-parameters.txt')
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 160 |
1 files changed, 85 insertions, 75 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index cc0ac035b8fe..b0a42f3564b6 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -106,11 +106,11 @@ use by PCI Format: <irq>,<irq>... - acpi_mask_gpe= [HW,ACPI] + acpi_mask_gpe= [HW,ACPI] Due to the existence of _Lxx/_Exx, some GPEs triggered by unsupported hardware/firmware features can result in - GPE floodings that cannot be automatically disabled by - the GPE dispatcher. + GPE floodings that cannot be automatically disabled by + the GPE dispatcher. This facility can be used to prevent such uncontrolled GPE floodings. Format: <int> @@ -472,10 +472,10 @@ for platform specific values (SB1, Loongson3 and others). - ccw_timeout_log [S390] + ccw_timeout_log [S390] See Documentation/s390/CommonIO for details. - cgroup_disable= [KNL] Disable a particular controller + cgroup_disable= [KNL] Disable a particular controller Format: {name of the controller(s) to disable} The effects of cgroup_disable=foo are: - foo isn't auto-mounted if you mount all cgroups in @@ -518,7 +518,7 @@ those clocks in any way. This parameter is useful for debug and development, but should not be needed on a platform with proper driver support. For more - information, see Documentation/clk.txt. + information, see Documentation/driver-api/clk.rst. clock= [BUGS=X86-32, HW] gettimeofday clocksource override. [Deprecated] @@ -641,8 +641,8 @@ hvc<n> Use the hypervisor console device <n>. This is for both Xen and PowerPC hypervisors. - If the device connected to the port is not a TTY but a braille - device, prepend "brl," before the device type, for instance + If the device connected to the port is not a TTY but a braille + device, prepend "brl," before the device type, for instance console=brl,ttyS0 For now, only VisioBraille is supported. @@ -662,7 +662,7 @@ consoleblank= [KNL] The console blank (screen saver) timeout in seconds. A value of 0 disables the blank timer. - Defaults to 0. + Defaults to 0. coredump_filter= [KNL] Change the default value for @@ -730,7 +730,7 @@ or memory reserved is below 4G. cryptomgr.notests - [KNL] Disable crypto self-tests + [KNL] Disable crypto self-tests cs89x0_dma= [HW,NET] Format: <dma> @@ -746,7 +746,7 @@ Format: <port#>,<type> See also Documentation/input/devices/joystick-parport.rst - ddebug_query= [KNL,DYNAMIC_DEBUG] Enable debug messages at early boot + ddebug_query= [KNL,DYNAMIC_DEBUG] Enable debug messages at early boot time. See Documentation/admin-guide/dynamic-debug-howto.rst for details. Deprecated, see dyndbg. @@ -833,7 +833,7 @@ causing system reset or hang due to sending INIT from AP to BSP. - disable_ddw [PPC/PSERIES] + disable_ddw [PPC/PSERIES] Disable Dynamic DMA Window support. Use this if to workaround buggy firmware. @@ -1188,7 +1188,7 @@ parameter will force ia64_sal_cache_flush to call ia64_pal_cache_flush instead of SAL_CACHE_FLUSH. - forcepae [X86-32] + forcepae [X86-32] Forcefully enable Physical Address Extension (PAE). Many Pentium M systems disable PAE but may have a functionally usable PAE implementation. @@ -1247,7 +1247,7 @@ gamma= [HW,DRM] - gart_fix_e820= [X86_64] disable the fix e820 for K8 GART + gart_fix_e820= [X86_64] disable the fix e820 for K8 GART Format: off | on default: on @@ -1341,23 +1341,32 @@ x86-64 are 2M (when the CPU supports "pse") and 1G (when the CPU supports the "pdpe1gb" cpuinfo flag). - hvc_iucv= [S390] Number of z/VM IUCV hypervisor console (HVC) - terminal devices. Valid values: 0..8 - hvc_iucv_allow= [S390] Comma-separated list of z/VM user IDs. - If specified, z/VM IUCV HVC accepts connections - from listed z/VM user IDs only. + hung_task_panic= + [KNL] Should the hung task detector generate panics. + Format: <integer> + A nonzero value instructs the kernel to panic when a + hung task is detected. The default value is controlled + by the CONFIG_BOOTPARAM_HUNG_TASK_PANIC build-time + option. The value selected by this boot parameter can + be changed later by the kernel.hung_task_panic sysctl. + + hvc_iucv= [S390] Number of z/VM IUCV hypervisor console (HVC) + terminal devices. Valid values: 0..8 + hvc_iucv_allow= [S390] Comma-separated list of z/VM user IDs. + If specified, z/VM IUCV HVC accepts connections + from listed z/VM user IDs only. keep_bootcon [KNL] Do not unregister boot console at start. This is only useful for debugging when something happens in the window between unregistering the boot console and initializing the real console. - i2c_bus= [HW] Override the default board specific I2C bus speed - or register an additional I2C bus that is not - registered from board initialization code. - Format: - <bus_id>,<clkrate> + i2c_bus= [HW] Override the default board specific I2C bus speed + or register an additional I2C bus that is not + registered from board initialization code. + Format: + <bus_id>,<clkrate> i8042.debug [HW] Toggle i8042 debug mode i8042.unmask_kbd_data @@ -1386,7 +1395,7 @@ Default: only on s2r transitions on x86; most other architectures force reset to be always executed i8042.unlock [HW] Unlock (ignore) the keylock - i8042.kbdreset [HW] Reset device connected to KBD port + i8042.kbdreset [HW] Reset device connected to KBD port i810= [HW,DRM] @@ -1548,13 +1557,13 @@ programs exec'd, files mmap'd for exec, and all files opened for read by uid=0. - ima_template= [IMA] + ima_template= [IMA] Select one of defined IMA measurements template formats. Formats: { "ima" | "ima-ng" | "ima-sig" } Default: "ima-ng" ima_template_fmt= - [IMA] Define a custom template format. + [IMA] Define a custom template format. Format: { "field1|...|fieldN" } ima.ahash_minsize= [IMA] Minimum file size for asynchronous hash usage @@ -1597,7 +1606,7 @@ inport.irq= [HW] Inport (ATI XL and Microsoft) busmouse driver Format: <irq> - int_pln_enable [x86] Enable power limit notification interrupt + int_pln_enable [x86] Enable power limit notification interrupt integrity_audit=[IMA] Format: { "0" | "1" } @@ -1650,39 +1659,39 @@ 0 disables intel_idle and fall back on acpi_idle. 1 to 9 specify maximum depth of C-state. - intel_pstate= [X86] - disable - Do not enable intel_pstate as the default - scaling driver for the supported processors - passive - Use intel_pstate as a scaling driver, but configure it - to work with generic cpufreq governors (instead of - enabling its internal governor). This mode cannot be - used along with the hardware-managed P-states (HWP) - feature. - force - Enable intel_pstate on systems that prohibit it by default - in favor of acpi-cpufreq. Forcing the intel_pstate driver - instead of acpi-cpufreq may disable platform features, such - as thermal controls and power capping, that rely on ACPI - P-States information being indicated to OSPM and therefore - should be used with caution. This option does not work with - processors that aren't supported by the intel_pstate driver - or on platforms that use pcc-cpufreq instead of acpi-cpufreq. - no_hwp - Do not enable hardware P state control (HWP) - if available. - hwp_only - Only load intel_pstate on systems which support - hardware P state control (HWP) if available. - support_acpi_ppc - Enforce ACPI _PPC performance limits. If the Fixed ACPI - Description Table, specifies preferred power management - profile as "Enterprise Server" or "Performance Server", - then this feature is turned on by default. - per_cpu_perf_limits - Allow per-logical-CPU P-State performance control limits using - cpufreq sysfs interface + intel_pstate= [X86] + disable + Do not enable intel_pstate as the default + scaling driver for the supported processors + passive + Use intel_pstate as a scaling driver, but configure it + to work with generic cpufreq governors (instead of + enabling its internal governor). This mode cannot be + used along with the hardware-managed P-states (HWP) + feature. + force + Enable intel_pstate on systems that prohibit it by default + in favor of acpi-cpufreq. Forcing the intel_pstate driver + instead of acpi-cpufreq may disable platform features, such + as thermal controls and power capping, that rely on ACPI + P-States information being indicated to OSPM and therefore + should be used with caution. This option does not work with + processors that aren't supported by the intel_pstate driver + or on platforms that use pcc-cpufreq instead of acpi-cpufreq. + no_hwp + Do not enable hardware P state control (HWP) + if available. + hwp_only + Only load intel_pstate on systems which support + hardware P state control (HWP) if available. + support_acpi_ppc + Enforce ACPI _PPC performance limits. If the Fixed ACPI + Description Table, specifies preferred power management + profile as "Enterprise Server" or "Performance Server", + then this feature is turned on by default. + per_cpu_perf_limits + Allow per-logical-CPU P-State performance control limits using + cpufreq sysfs interface intremap= [X86-64, Intel-IOMMU] on enable Interrupt Remapping (default) @@ -2026,7 +2035,7 @@ * [no]ncqtrim: Turn off queued DSM TRIM. * nohrst, nosrst, norst: suppress hard, soft - and both resets. + and both resets. * rstonce: only attempt one reset during hot-unplug link recovery @@ -2214,7 +2223,7 @@ [KNL,SH] Allow user to override the default size for per-device physically contiguous DMA buffers. - memhp_default_state=online/offline + memhp_default_state=online/offline [KNL] Set the initial state for the memory hotplug onlining policy. If not specified, the default value is set according to the @@ -2764,7 +2773,7 @@ [X86,PV_OPS] Disable paravirtualized VMware scheduler clock and use the default one. - no-steal-acc [X86,KVM] Disable paravirtualized steal time accounting. + no-steal-acc [X86,KVM] Disable paravirtualized steal time accounting. steal time is computed, but won't influence scheduler behaviour @@ -2825,7 +2834,7 @@ notsc [BUGS=X86-32] Disable Time Stamp Counter nowatchdog [KNL] Disable both lockup detectors, i.e. - soft-lockup and NMI watchdog (hard-lockup). + soft-lockup and NMI watchdog (hard-lockup). nowb [ARM] @@ -2845,7 +2854,7 @@ If the dependencies are under your control, you can turn on cpu0_hotplug. - nps_mtm_hs_ctr= [KNL,ARC] + nps_mtm_hs_ctr= [KNL,ARC] This parameter sets the maximum duration, in cycles, each HW thread of the CTOP can run without interruptions, before HW switches it. @@ -2986,7 +2995,7 @@ pci=option[,option...] [PCI] various PCI subsystem options: earlydump [X86] dump PCI config space before the kernel - changes anything + changes anything off [X86] don't probe for the PCI bus bios [X86-32] force use of PCI BIOS, don't access the hardware directly. Use this if your machine @@ -3074,7 +3083,7 @@ is enabled by default. If you need to use this, please report a bug. nocrs [X86] Ignore PCI host bridge windows from ACPI. - If you need to use this, please report a bug. + If you need to use this, please report a bug. routeirq Do IRQ routing for all PCI devices. This is normally done in pci_enable_device(), so this option is a temporary workaround @@ -3917,7 +3926,7 @@ cache (risks via metadata attacks are mostly unchanged). Debug options disable merging on their own. - For more information see Documentation/vm/slub.txt. + For more information see Documentation/vm/slub.rst. slab_max_order= [MM, SLAB] Determines the maximum allowed order for slabs. @@ -3931,7 +3940,7 @@ slub_debug can create guard zones around objects and may poison objects when not in use. Also tracks the last alloc / free. For more information see - Documentation/vm/slub.txt. + Documentation/vm/slub.rst. slub_memcg_sysfs= [MM, SLUB] Determines whether to enable sysfs directories for @@ -3945,7 +3954,7 @@ Determines the maximum allowed order for slabs. A high setting may cause OOMs due to memory fragmentation. For more information see - Documentation/vm/slub.txt. + Documentation/vm/slub.rst. slub_min_objects= [MM, SLUB] The minimum number of objects per slab. SLUB will @@ -3954,12 +3963,12 @@ the number of objects indicated. The higher the number of objects the smaller the overhead of tracking slabs and the less frequently locks need to be acquired. - For more information see Documentation/vm/slub.txt. + For more information see Documentation/vm/slub.rst. slub_min_order= [MM, SLUB] Determines the minimum page order for slabs. Must be lower than slub_max_order. - For more information see Documentation/vm/slub.txt. + For more information see Documentation/vm/slub.rst. slub_nomerge [MM, SLUB] Same with slab_nomerge. This is supported for legacy. @@ -4357,7 +4366,8 @@ Format: [always|madvise|never] Can be used to control the default behavior of the system with respect to transparent hugepages. - See Documentation/vm/transhuge.txt for more details. + See Documentation/admin-guide/mm/transhuge.rst + for more details. tsc= Disable clocksource stability checks for TSC. Format: <string> @@ -4435,7 +4445,7 @@ usbcore.initial_descriptor_timeout= [USB] Specifies timeout for the initial 64-byte - USB_REQ_GET_DESCRIPTOR request in milliseconds + USB_REQ_GET_DESCRIPTOR request in milliseconds (default 5000 = 5.0 seconds). usbcore.nousb [USB] Disable the USB subsystem |