Lines Matching +full:enforce +full:- +full:video +full:- +full:mode
5 force -- enable ACPI if default was off
6 on -- enable ACPI but allow fallback to DT [arm64]
7 off -- disable ACPI if default was on
8 noirq -- do not use ACPI for IRQ routing
9 strict -- Be less tolerant of platforms that are not
11 rsdt -- prefer RSDT over (default) XSDT
12 copy_dsdt -- copy DSDT to memory
25 { vendor | video | native | none }
26 If set to vendor, prefer vendor-specific driver
28 of the ACPI video.ko driver.
29 If set to video, use the ACPI video.ko driver.
30 If set to native, use the device's native backlight mode.
58 Documentation/firmware-guide/acpi/debug.rst for more information about
98 default in APIC mode
102 default in PIC mode
121 Disable auto-serialization of AML methods
124 auto-serialization feature.
142 Ignore the ACPI-based watchdog interface (WDAT) and let
163 acpi_osi=! # disable all built-in OS vendor
165 acpi_osi=!! # enable all built-in OS vendor
222 acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
227 For broken nForce2 BIOS resulting in XT-PIC timer.
232 See Documentation/power/video.rst for information on
235 as soon as the kernel's real-mode entry point is called.
265 See Documentation/sound/alsa-configuration.rst
272 align_va_addr= [X86-64]
277 CPU-intensive style benchmark, and it can vary highly in
280 32: only for 32-bit processes
281 64: only for 64-bit processes
282 on: enable for both 32- and 64-bit processes
283 off: disable for both 32- and 64-bit processes
292 amd_iommu= [HW,X86-64]
295 fullflush - enable flushing of IO/TLB entries when
299 off - do not initialize any AMD IOMMU found in
301 force_isolation - Force device isolation for all
307 amd_iommu_dump= [HW,X86-64]
313 amd_iommu_intr= [HW,X86-64]
316 legacy - Use legacy interrupt remapping mode.
317 vapic - Use virtual APIC mode, which allows IOMMU
319 This mode requires kvm-amd.avic=1.
333 Power management functions (SPARCstation-4/5 + deriv.)
335 Disable APC CPU standby support. SPARCstation-Fox does
336 not play well with APC CPU idle - disable it if you have
343 when initialising the APIC and IO-APIC components.
344 For X86-32, this can also be used to specify an APIC
364 to set it to "all" by meaning -- no limit here.
373 arcrimi= [HW,NET] ARCnet - "RIM I" (entirely mem-mapped) cards
391 atkbd.softraw= [HW] Choose between synthetic and real raw mode
397 audit= [KNL] Enable the audit sub-system
399 0 | off - kernel audit is disabled and can not be
401 unset - kernel audit is initialized but disabled and
403 1 | on - kernel audit is initialized and partially
416 0 - Disable the BAU.
417 1 - Enable the BAU.
418 unset - Disable the BAU.
421 Format: <io>,<mode>
424 Format: <io>,<mode>
428 BayCom Serial Port AX.25 Modem (Full Duplex Mode)
429 Format: <io>,<irq>,<mode>[,<baud>]
433 BayCom Serial Port AX.25 Modem (Half Duplex Mode)
434 Format: <io>,<irq>,<mode>
439 See Documentation/block/cmdline-partition.rst
450 See Documentation/admin-guide/bootconfig.rst
461 bttv.pll= See Documentation/admin-guide/media/bttv.rst
470 cachesize= [BUGS=X86-32] Override level 2 CPU cache size detection.
489 inclusive. See arch/mips/include/asm/pgtable-bits.h
499 - foo isn't auto-mounted if you mount all cgroups in
501 - foo isn't visible as an individually mountable
518 nosocket -- Disable socket memory accounting.
519 nokmem -- Disable kernel memory accounting.
520 kmem -- Enable kernel memory accounting.
525 0 -- check protection applied by kernel (includes
527 1 -- check protection requested by application.
541 force such clocks to be always-on nor does it reserve
545 information, see Documentation/driver-api/clk.rst.
547 clock= [BUGS=X86-32, HW] gettimeofday clocksource override.
564 [X86-32] pit,hpet,tsc;
571 [X86-64] hpet,tsc
577 architected timer so that code using WFE-based polling
600 cma=nn[MG]@[start[MG][-end[MG]]]
611 Sets the size of kernel per-numa memory area for
613 per-numa CMA altogether. And If this option is not
615 With per-numa CMA enabled, DMA users on node nid will
631 com20020= [HW,NET] ARCnet - COM20020 chipset
635 com90io= [HW,NET] ARCnet - COM90xx chipset (IO-mapped buffers)
639 ARCnet - COM90xx chipset (memory-mapped buffers)
657 See Documentation/admin-guide/serial-console.rst for more
667 Start an early, polled-mode console on the 8250/16550
670 MMIO inter-register address stride is either 8-bit
671 (mmio), 16-bit (mmio16), or 32-bit (mmio32).
675 the h/w is not re-initialized.
696 syscall, or to executing "dmesg -S --raw" or to reading
716 disable the cpuidle sub-system
722 disable the cpufreq sub-system
730 [X86] Delay for N microsec between assert and de-assert
745 [KNL, X86-64] Select a region under 4G first, and
748 See Documentation/admin-guide/kdump/kdump.rst for further details.
753 start-[end] where start and end are both
755 Documentation/admin-guide/kdump/kdump.rst for an example.
758 [KNL, X86-64] range could be above 4G. Allow kernel
765 [KNL, X86-64] range under 4G. When crashkernel=X,high
770 low memory is needed to make sure DMA buffers for 32-bit
780 [KNL] Disable crypto self-tests
794 See also Documentation/input/devices/joystick-parport.rst
798 Documentation/admin-guide/dynamic-debug-howto.rst for
812 [KNL] verbose self-tests
815 self-tests.
817 1 will print _a lot_ more information - normally
855 Format: { on, no-mount, off }
857 no-mount:
862 get a -EPERM as result when trying to register files
866 Default value is set in build-time with a kernel configuration.
882 Documentation/admin-guide/mm/hugetlbpage.rst.
929 against bounds-checking flaws in the kernel's
935 Disable RADIX MMU mode on POWER9
989 entries for DMA-API debugging code. One entry is
990 required per DMA-API allocation. Use this if the
991 DMA-API debugging code disables itself because the
995 With this option the DMA-API debugging driver
1010 Generic built-in EDID data sets are used, if one of
1015 available in Documentation/admin-guide/edid.rst. An EDID
1027 Control how the dt_cpu_ftrs device-tree binding is
1037 what data is available or for reverse-engineering.
1042 Documentation/admin-guide/dynamic-debug-howto.rst
1059 determined by stdout-path property in device tree's
1064 Start an early, polled-mode console on a Cadence
1075 Start an early, polled-mode console on the 8250/16550
1077 MMIO inter-register address stride is either 8-bit
1078 (mmio) or 32-bit (mmio32 or mmio32be).
1086 Start an early, polled-mode console on a pl011 serial
1090 the driver will use only 32-bit accessors to read/write
1094 Start an early, polled-mode console on a meson serial
1100 Start an early, polled-mode console on an msm serial
1106 Start an early, polled-mode console on an msm serial
1112 Start an early, polled-mode console on a serial port
1118 Start an early, polled-mode console on a serial port
1124 Use RISC-V SBI (Supervisor Binary Interface) for early
1142 Start an early, polled-mode console on a lantiq serial
1156 Start an early, polled-mode, output-only console on the
1161 Start an early, polled-mode console on the
1167 Start an early, polled-mode console on a Qualcomm
1175 coherent non-x86 systems that use system memory for
1234 force: enforce the use of EDAC to report H/W event.
1286 attribute is added to range 0x100000000-0x180000000 and
1287 0x10a0000000-0x1120000000.
1291 range 0x240000000-0x43fffffff.
1303 Documentation/admin-guide/acpi/ssdt-overlays.rst for details.
1309 elanfreq= [X86-32]
1317 See Documentation/admin-guide/kdump/kdump.rst for details.
1333 0 -- permissive (log only, no denials).
1334 1 -- enforcing (deny and log).
1337 /sys/fs/selinux/enforce.
1358 See also Documentation/fault-injection/.
1362 See Documentation/admin-guide/sysctl/net.rst for
1366 See Documentation/admin-guide/blockdev/floppy.rst.
1369 [IA-64] Avoid check_sal_cache_flush which may hang on
1374 forcepae [X86-32]
1393 ftrace_filter=[function-list]
1395 tracer at boot up. function-list is a comma separated
1400 ftrace_notrace=[function-list]
1402 function-list. This list can be changed at run time
1406 ftrace_graph_filter=[function-list]
1409 function-list is a comma separated list of functions
1413 ftrace_graph_notrace=[function-list]
1415 function-list. This list is a comma separated list of
1435 off -- Don't create device links from firmware info.
1436 permissive -- Create device links from firmware info
1439 on -- Create device links from firmware info and use it
1440 to enforce probe and suspend/resume ordering.
1441 rpm -- Like "on", but also use to order runtime PM.
1447 See also Documentation/input/devices/joystick-parport.rst
1451 gart_fix_e820= [X86-64] disable the fix e820 for K8 GART
1455 gcov_persist= [GCOV] When non-zero (default), profiling data for
1488 gpio-mockup.gpio_mockup_ranges
1493 [KNL] Should the hard-lockup detector generate
1499 for 64-bit NUMA, off otherwise.
1502 hcl= [IA-64] SGI's Hardware Graph compatibility layer
1509 corresponding firmware-first mode error processing
1517 highres= [KNL] Enable/disable high resolution timer mode.
1523 hpet= [X86-32,HPET] option to control HPET usage
1540 boot-time allocation of gigantic hugepages is skipped.
1548 Documentation/admin-guide/mm/hugetlbpage.rst.
1558 Documentation/admin-guide/mm/hugetlbpage.rst.
1567 by the CONFIG_BOOTPARAM_HUNG_TASK_PANIC build-time
1573 hvc_iucv_allow= [S390] Comma-separated list of z/VM user IDs.
1593 i8042.debug [HW] Toggle i8042 debug mode
1596 (disabled by default, and as a pre-condition
1598 i8042.direct [HW] Put keyboard port into non-translated mode
1612 suspend-to-ram transitions, only during s2r
1647 -1 -- never invert brightness
1648 0 -- machine default
1649 1 -- force brightness inversion
1654 ide-core.nodma= [HW] (E)IDE subsystem
1660 ide-generic.probe-mask= [HW] (E)IDE subsystem
1672 ide-pci-generic.all-generic-ide [HW] (E)IDE subsystem
1683 idle=nomwait: Disable mwait for CPU C-states
1685 ieee754= [MIPS] Select IEEE Std 754 conformance mode
1695 encoding mode.
1700 legacy only accept legacy-NaN binaries, if supported
1702 2008 only accept 2008-NaN binaries, if supported
1711 'relaxed' straps the emulator for both legacy-NaN and
1712 2008-NaN, whereas 'strict' enables legacy-NaN only on
1717 mode generally follows that for the NaN encoding,
1721 Ignore loglevel setting - this will print /all/
1736 Format: { "off" | "enforce" | "fix" | "log" }
1737 default: "enforce"
1762 mode bit set by either the effective uid (euid=0) or
1785 Formats: { "ima" | "ima-ng" | "ima-sig" }
1786 Default: "ima-ng"
1818 initcall_blacklist= [KNL] Do not execute a comma-separated list of
1819 initcall functions. Useful for debugging built-in
1852 0 -- basic integrity auditing messages. (Default)
1853 1 -- additional integrity auditing messages.
1866 forcedac [X86-64]
1868 for io virtual address below 32-bit forcing dual
1870 than 32-bit addressing. The default is to look
1871 for translation below 32-bit and if not available
1882 By default, scalable mode will be disabled even if the
1884 mode translation. With this option set, scalable mode
1889 could harm performance of some high-throughput
1903 1 to 9 specify maximum depth of C-state.
1912 enabling its internal governor). This mode cannot be
1913 used along with the hardware-managed P-states (HWP)
1917 in favor of acpi-cpufreq. Forcing the intel_pstate driver
1918 instead of acpi-cpufreq may disable platform features, such
1920 P-States information being indicated to OSPM and therefore
1923 or on platforms that use pcc-cpufreq instead of acpi-cpufreq.
1931 Enforce ACPI _PPC performance limits. If the Fixed ACPI
1936 Allow per-logical-CPU P-State performance control limits using
1939 intremap= [X86-64, Intel-IOMMU]
1944 BIOS x2APIC opt-out request will be ignored
1968 0 - Lazy mode.
1972 Will fall back to strict mode if not supported by
1974 1 - Strict mode (default).
1981 0 - Use IOMMU translation for DMA.
1982 1 - Bypass the IOMMU for DMA.
1983 unset - Use value of CONFIG_IOMMU_DEFAULT_PASSTHROUGH.
1985 io7= [HW] IO7 for Marvel-based Alpha systems
2000 See Documentation/admin-guide/nfs/nfsroot.rst.
2024 Enables support for pseudo-NMIs in the kernel. This
2043 [Deprecated - use cpusets instead]
2044 Format: [flag-list,]<cpu-list>
2075 "number of CPUs in system - 1".
2101 The format of <cpu-list> is described above.
2105 ivrs_ioapic [HW,X86-64]
2106 Provide an override to the IOAPIC-ID<->DEVICE-ID
2110 For example, to map IOAPIC-ID decimal 10 to
2116 * To map IOAPIC-ID decimal 10 to PCI device 00:14.0
2119 * To map IOAPIC-ID decimal 10 to PCI segment 0x1 and
2123 ivrs_hpet [HW,X86-64]
2124 Provide an override to the HPET-ID<->DEVICE-ID
2128 For example, to map HPET-ID decimal 10 to
2134 * To map HPET-ID decimal 0 to PCI device 00:14.0
2137 * To map HPET-ID decimal 10 to PCI segment 0x1 and
2141 ivrs_acpihid [HW,X86-64]
2142 Provide an override to the ACPI-HID:UID<->DEVICE-ID
2146 For example, to map UART-HID:UID AMD0020:0 to
2152 * To map UART-HID:UID AMD0020:0 to PCI segment is 0,
2155 * To map UART-HID:UID AMD0020:0 to PCI segment 0x1 and
2168 [KNL] Enforce KASAN (Kernel Address Sanitizer) to print
2175 kernelcore= [KNL,X86,IA-64,PPC]
2178 the kernel for non-movable allocations. The requested
2188 subsystem. Note that allocations like PTEs-from-HighMem
2196 for non-movable allocations and remaining memory is used
2207 gdb or control-c on the dbgp connection. When
2208 not using this parameter you use sysrq-g to break into
2213 or a supported polling keyboard driver (non-usb).
2217 Optional Kernel mode setting:
2223 characters and can work in polling mode, you can use
2240 Configure the RouterBoard 532 series on-chip
2243 kmemleak= [KNL] Boot-time kmemleak enable/disable
2249 kprobe_event=[probe-list]
2251 The probe-list is a semicolon delimited list of probe
2297 kvm-amd.nested= [KVM,AMD] Allow nested virtualization in KVM/SVM.
2300 kvm-amd.npt= [KVM,AMD] Disable nested paging (virtualized MMU)
2302 Default is 1 (enabled) if in 64-bit or 32-bit PAE mode.
2304 kvm-arm.vgic_v3_group0_trap=
2305 [KVM,ARM] Trap guest accesses to GICv3 group-0
2308 kvm-arm.vgic_v3_group1_trap=
2309 [KVM,ARM] Trap guest accesses to GICv3 group-1
2312 kvm-arm.vgic_v3_common_trap=
2316 kvm-arm.vgic_v4_enable=
2328 kvm-intel.ept= [KVM,Intel] Disable extended page tables
2332 kvm-intel.emulate_invalid_guest_state=
2334 Ignored if kvm-intel.enable_unrestricted_guest=1, as
2340 kvm-intel.flexpriority=
2344 kvm-intel.nested=
2348 kvm-intel.unrestricted_guest=
2350 (virtualized real and unpaged mode) on capable
2353 kvm-intel.vmentry_l1d_flush=[KVM,Intel] Mitigation for L1 Terminal Fault
2354 CVE-2018-3620.
2365 kvm-intel.vpid= [KVM,Intel] Disable Virtual Processor Identification
2432 For details see: Documentation/admin-guide/hw-vuln/l1tf.rst
2438 lapic [X86-32,APIC] Enable the local APIC even if BIOS
2442 value for LAPIC timer one-shot implementation. Default
2477 first fan-out link behind PMP device. It does not
2491 * Transfer mode: pio[0-7], mwdma[0-4] and udma[0-7].
2503 hot-unplug link recovery
2540 Set the number of locking read-acquisition kthreads.
2545 Set the number of locking write-acquisition kthreads.
2548 Set time (s) after boot for CPU-hotplug testing.
2551 Set time (s) between CPU-hotplug operations, or
2552 zero to disable CPU-hotplug testing.
2555 Set task-shuffle interval (jiffies). Shuffling
2556 tasks allows some CPUs to go into dyntick-idle
2557 mode during the locktorture test.
2561 is useful for hands-off automated testing.
2594 7 (KERN_DEBUG) debug-level messages
2604 logo.nologo [FB] Disables display of the built-in Linux logo.
2622 an IEEE 1284-compliant printer is attached; if
2628 time-consuming boot-time autodetection (up to 250 ms per
2649 machvec= [IA-64] Force the use of a particular machine-vector
2655 Example: machtype=lemote-yeeloong-2f-7inch
2670 (loop.max_loop) unconditionally pre-created at init time. The default
2673 devices can be requested on-demand with the
2674 /dev/loop-control interface.
2676 mce [X86-32] Machine Check Exception
2678 mce=option [X86-64] See Documentation/x86/x86_64/boot-options.rst
2681 See Documentation/admin-guide/md.rst.
2688 Control mitigation for the Micro-architectural Data
2703 full - Enable MDS mitigation on vulnerable CPUs
2704 full,nosmt - Enable MDS mitigation and disable
2706 off - Unconditionally disable MDS mitigation
2708 On TAA-affected machines, mds=off can be prevented by
2717 For details see: Documentation/admin-guide/hw-vuln/mds.rst
2736 mem=nopentium [BUGS=X86-32] Disable usage of 4MB pages for kernel
2741 per-device physically contiguous DMA buffers.
2749 See Documentation/admin-guide/mm/memory-hotplug.rst.
2774 Example: Exclude memory from 0x18690000-0x1869ffff
2788 memmap=<size>%<offset>-<oldtype>+<newtype>
2790 from <oldtype> to <newtype>. If "-<oldtype>" is left
2805 repeatable BIOS-originated corruption always
2830 mem_encrypt= [X86-64] AMD Secure Memory Encryption (SME) control
2838 Refer to Documentation/virt/kvm/amd-memory-encryption.rst
2841 mem_sleep_default= [SUSPEND] Default system suspend mode:
2842 s2idle - Suspend-To-Idle
2843 shallow - Power-On Suspend or equivalent (if supported)
2844 deep - Suspend-To-RAM or equivalent (if supported)
2845 See Documentation/admin-guide/pm/sleep-states.rst.
2848 See Documentation/admin-guide/media/meye.rst.
2850 mfgpt_irq= [IA-32] Specify the IRQ to use for the
2851 Multi-Function General Purpose Timers on AMD Geode
2854 mfgptfix [X86-32] Fix MFGPT timers on AMD Geode platforms when
2868 0 - The attached screen is the 3.5" TFT
2869 1 - The attached screen is the 7" TFT
2870 2 - The VGA Shield is attached (1024x768)
2874 b - Enable backlight. The TFT backlight pin will be
2878 c - Enable the s3c camera interface.
2879 t - Reserved for enabling touchscreen support. The
2883 https://repo.or.cz/w/linux-2.6/mini2440.git
2888 arch-independent options, each of which is an
2889 aggregation of existing arch-specific options.
2902 ssbd=force-off [ARM64]
2922 have other ways of avoiding SMT-based attacks.
2957 full - Enable mitigation on vulnerable CPUs
2959 full,nosmt - Enable mitigation and disable SMT on
2962 off - Unconditionally disable mitigation
2975 Documentation/admin-guide/hw-vuln/processor_mmio_stale_data.rst
2983 module_blacklist= [KNL] Do not load a comma-separated list of
2990 touchpads working in absolute mode only).
2997 movablecore= [KNL,X86,IA-64,PPC]
3008 movable_node [KNL] Boot-time switch to make hotplugable memory
3015 Format: <name>,<region-number>,<size>,<offset>
3018 <name>,<region-number>[,<base>,<size>,<buswidth>,<altbuswidth>]
3027 onenand.bdry= [HW,MTD] Flex-OneNAND Boundary Configuration
3031 boundary - index of last SLC block on Flex-OneNAND.
3033 lock - Configure if Flex-OneNAND boundary should be locked.
3040 See arch/arm/mach-s3c2412/mach-jive.c
3068 something different and driver-specific.
3079 See Documentation/admin-guide/nfs/nfsroot.rst.
3081 nfsroot= [NFS] nfs root filesystem for disk-less boxes.
3082 See Documentation/admin-guide/nfs/nfsroot.rst.
3085 See Documentation/admin-guide/nfs/nfsroot.rst.
3109 [NFS] enable 64-bit inode numbers.
3110 If zero, the NFS client will fake up a 32-bit inode
3112 of returning the full 64-bit number.
3113 The default is to return 64-bit inode numbers.
3138 Servers that do not support this mode of operation
3143 [NFS4] Specify an additional fixed unique ident-
3174 driver. A non-zero value sets the minimum interval
3186 NMI stack-backtrace request.
3195 0 - turn hardlockup detector in nmi_watchdog off
3196 1 - turn hardlockup detector in nmi_watchdog on
3213 no387 [BUGS=X86-32] Tells the kernel to use the 387 maths
3217 no5lvl [X86-64] Disable 5-level paging mode. Forces
3218 kernel to use 4-level paging instead.
3249 caches in the slab allocator. Saves per-node memory,
3269 nodelayacct [KNL] Disable per-task delay accounting
3275 no_entry_flush [PPC] Don't flush the L1-D cache when entering the kernel.
3277 noexec [IA-64]
3280 On X86-32 available only on PAE configured kernels.
3281 noexec=on: enable non-executable mappings (default)
3282 noexec=off: disable non-executable mappings
3285 Disable SMAP (Supervisor Mode Access Prevention)
3289 Disable SMEP (Supervisor Mode Execution Prevention)
3292 noexec32 [X86-64]
3293 This affects only 32-bit executables.
3294 noexec32=on: enable non-executable mappings (default)
3296 noexec32=off: disable non-executable mappings
3301 nofxsr [BUGS=X86-32] Disables x86 floating point extended
3303 legacy floating-point registers on task switch.
3327 [PPC] Don't flush the L1-D cache after accessing user data.
3331 enabling legacy floating-point and sse state.
3356 nohalt [IA-64] Tells the kernel not to use the power saving
3358 power-consumption. On the positive side, it reduces
3359 interrupt wake-up latency, which may improve performance
3361 real-time systems.
3381 noirqdebug [X86-32] Disables the code which attempts to detect and
3392 nointremap [X86-64, Intel-IOMMU] Do not enable interrupt
3394 [Deprecated - use intremap=off]
3396 nointroute [IA-64]
3400 nojitter [IA-64] Disables jitter checking for ITC timers.
3402 no-kvmclock [X86,KVM] Disable paravirtualized KVM clock driver
3404 no-kvmapf [X86,KVM] Disable paravirtualized asynchronous page
3407 no-vmw-sched-clock
3411 no-steal-acc [X86,PV_OPS,ARM64] Disable paravirtualized steal time
3415 nolapic [X86-32,APIC] Do not enable or use the local APIC.
3417 nolapic_timer [X86-32,APIC] Do not use the local APIC timer.
3422 nomca [IA-64] Disable machine check abort handling
3424 nomce [X86-32] Disable Machine Check Exception
3426 nomfgpt [X86-32] Disable Multi-Function General Purpose
3438 nopcid [X86-64] Disable the PCID cpu feature.
3443 noreplace-smp [X86-32,SMP] Don't replace SMP instructions
3454 no-scroll [VGA] Disables scrollback.
3455 This is required for the Braillex ib80-piezo Braille
3458 nosbagart [IA-64]
3460 nosep [BUGS=X86-32] Disables x86 SYSENTER/SYSEXIT support.
3465 nosoftlockup [KNL] Disable the soft-lockup detector.
3470 soft-lockup and NMI watchdog (hard-lockup).
3474 nox2apic [X86-64,APIC] Do not enable x2APIC mode.
3499 nptcg= [IA-64] Override max number of concurrent global TLB
3508 n. So during boot up some boot time memory for per-cpu
3509 variables need be pre-allocated for later physical cpu
3520 See Documentation/admin-guide/sysctl/vm.rst for details.
3523 See Documentation/core-api/debugging-via-ohci1394.rst for more
3549 timer mode (see also oprofile.timer
3550 for generic hr timer mode)
3562 running on a platform with a direct-mapped memory-side
3568 page_owner= [KNL] Boot-time page_owner enabling option.
3574 page_poison= [KNL] Boot-time parameter changing the state of
3604 See Documentation/admin-guide/tainted-kernels.rst for
3612 Run kdump after running panic-notifiers and dumping
3622 parkbd.mode= [HW] Parallel port keyboard adapter mode of operation,
3624 Format: <mode>
3642 a specific mode. This is necessary on Pegasos
3644 up parallel port mode and sets it to spp.
3657 See also Documentation/admin-guide/blockdev/paride.rst.
3686 bios [X86-32] force use of PCI BIOS, don't access
3688 has a non-standard PCI host bridge.
3689 nobios [X86-32] disallow use of PCI BIOS, only direct
3695 data in IO port 0xCFC, both 32-bit).
3697 Mechanism 2 (IO port 0xCF8 is an 8-bit port for
3698 the function, IO port 0xCFA, also 8-bit, sets
3700 through ports 0xC000-0xCFFF).
3707 root domains (aka PCI segments, in ACPI-speak).
3715 disable the use of MSI interrupts system-wide.
3720 primary IO-APIC for bridges that cannot disable
3727 biosirq [X86-32] Use PCI BIOS calls to get the interrupt
3751 F0000h-100000h range.
3756 assign-busses [X86] Always assign all PCI bus
3784 bfsort Sort PCI devices into breadth-first order.
3787 nobfsort Don't sort PCI devices into breadth-first order.
3789 tuning and use the BIOS-configured MPS defaults.
3799 configuration allows peer-to-peer DMA between
3802 that hot-added devices will work.
3817 A PCI-PCI bridge can be specified if resource
3823 for 4096-byte alignment.
3825 end-to-end CRC checking).
3854 noats [PCIE, Intel-IOMMU, AMD-IOMMU]
3890 dpc-native Use native PCIe service for DPC only. May
3907 Keep all power-domains already enabled by bootloader on,
3913 See Documentation/admin-guide/blockdev/paride.rst.
3928 See Documentation/admin-guide/blockdev/paride.rst.
3931 See Documentation/admin-guide/blockdev/paride.rst.
3933 pirq= [SMP,APIC] Manual mp-table setup
3934 See Documentation/x86/i386/IO-APIC.rst.
3938 See also Documentation/admin-guide/parport.rst.
3949 CONFIG_PNP_DEBUG_MESSAGES option). Change at run-time
3958 { on | off | curr | res | no-curr | no-res }
3996 print-fatal-signals=
4002 coredump - etc.
4005 you might want to try "ulimit -i unlimited".
4017 on - unlimited logging to /dev/kmsg from userspace
4018 off - logging to /dev/kmsg disabled
4019 ratelimit - ratelimit the logging
4026 Limit processor to maximum C-state
4030 Ignore the _CST method to determine C-states,
4037 Param: "schedule" - profile schedule points.
4038 Param: "sleep" - profile D-state sleeping (millisecs).
4040 Param: "kvm" - profile VM exits.
4041 Param: <number> - step/bucket size as a power of 2 for
4071 See Documentation/admin-guide/blockdev/paride.rst.
4073 pti= [X86-64] Control Page Table Isolation of user and
4078 on - unconditionally enable
4079 off - unconditionally disable
4080 auto - kernel detects whether your CPU model is
4085 nopti [X86-64]
4089 [KNL] Number of legacy pty's. Overwrites compiled-in
4097 See Documentation/admin-guide/md.rst.
4100 See Documentation/admin-guide/blockdev/ramdisk.rst.
4116 ras=option[,option,...] [KNL] RAS-specific options
4128 the specified list of CPUs to be no-callback CPUs.
4131 purpose, where "x" is "p" for RCU-preempt, and
4132 "s" for RCU-sched, and "N" is the CPU number.
4134 which can be useful for HPC and real-time
4143 This improves the real-time response for the
4160 RCU grace-period cleanup.
4164 RCU grace-period initialization.
4168 RCU grace-period pre-initialization, that is,
4169 the propagation of recent CPU-hotplug changes up
4174 per-CPU rcuc kthreads. Defaults to a non-zero
4182 cache-to-cache transfer latencies.
4188 and for NUMA systems with large remote-access
4201 Set delay from grace-period initialization to
4214 soliciting quiescent-state help from
4226 Set the SCHED_FIFO priority of the RCU per-CPU
4229 and for the RCU grace-period kthreads (rcu_bh,
4231 set, valid values are 1-99 and the default is 1
4232 (the least-favored priority). Otherwise, when
4233 RCU_BOOST is not set, valid values are 0-99 and
4234 the default is zero (non-realtime operation).
4240 the wakeup overhead on the global grace-period
4242 each group's NOCB grace-period kthread.
4250 batch limiting is re-enabled.
4254 RCU's force-quiescent-state scan will aggressively
4272 Cause the grace-period kthread to get an extra
4274 it should at force-quiescent-state time.
4280 this specifies an rcu_read_unlock()-time delay
4284 of RCU-protected pointers after the relevant
4294 grace-period primitives such as call_rcu().
4305 grace-period primitives.
4308 Set test-start holdoff period. The purpose of
4327 Set number of RCU readers. The value -1 selects
4329 "n" less than -1 selects N-n+1, where N is again
4330 the number of CPUs. For example, -2 selects N
4331 (the number of CPUs), -3 selects N+1, and so on.
4332 A value of "n" less than or equal to -N selects
4345 complete. This is useful for hands-off automated
4352 Write-side holdoff between grace periods,
4369 Enable RCU grace-period forward-progress testing
4373 Specify the fraction of a CPU-stall-warning
4374 period to do tight-loop forward-progress testing.
4378 forward-progress tests.
4382 need_resched() during tight-loop forward-progress
4386 Use conditional/asynchronous update-side
4390 Use expedited update-side primitives, if available.
4393 Use normal (non-expedited) asynchronous
4394 update-side primitives, if available.
4397 Use normal (non-expedited) synchronous
4398 update-side primitives, if available. If all
4402 they are all non-zero.
4410 Leak an RCU-protected pointer out of the reader.
4425 Set number of RCU readers. The value -1 selects
4426 N-1, where N is the number of CPUs. A value
4427 "n" less than -1 selects N-n-2, where N is again
4428 the number of CPUs. For example, -2 selects N
4429 (the number of CPUs), -3 selects N+1, and so on.
4432 Enable debug-object double-call_rcu() testing.
4435 Set time (s) after boot for CPU-hotplug testing.
4438 Set time (jiffies) between CPU-hotplug operations,
4439 or zero to disable CPU-hotplug testing.
4442 Set the number of read-then-exit kthreads used
4444 task-exit processing.
4447 The number of times in a given read-then-exit
4448 episode that a set of read-then-exit kthreads
4453 read-then-exit testing episodes.
4456 Set task-shuffle interval (s). Shuffling tasks
4457 allows some CPUs to go into dyntick-idle mode
4462 is useful for hands-off automated testing.
4471 to any other stall-related activity.
4481 grace-period kthread to test RCU CPU stall
4507 Test RCU's dyntick-idle handling. See also the
4533 Use expedited grace-period primitives, for
4537 real-time latency, and degrade energy efficiency.
4541 Use only normal grace-period primitives,
4544 real-time latency, CPU utilization, and
4546 increased grace-period latency. This parameter
4553 only normal grace-period primitives. No effect
4560 number avoids disturbing real-time workloads,
4577 force - Override the decision by the kernel to hide the
4597 (prefix with 'panic_' to set mode for panic
4605 Set test-start holdoff period. The purpose of
4614 but the default has already reduced the per-pass
4619 Set number of readers. The default value of -1
4628 Set the read-side critical-section duration,
4632 Specify the read-protection implementation to test.
4645 See Documentation/admin-guide/cgroup-v1/cpusets.rst.
4653 reservetop= [X86-32]
4675 See Documentation/power/swsusp-and-swap-files.rst
4691 during restoration read-only).
4699 AMD-based UNRET and IBPB mitigations alone do not stop
4701 sibling threads. For that reason, STIBP is used on pro-
4705 off - no mitigation
4706 auto - automatically select a migitation
4707 auto,nosmt - automatically select a mitigation,
4711 ibpb - On AMD, mitigate short speculation
4716 ibpb,nosmt - Like "ibpb" above but will disable SMT
4720 unret - Force enable untrained return thunks,
4721 only effective on AMD f15h-f17h based
4723 unret,nosmt - Like unret, but will disable SMT when STIBP
4733 0 "airplane mode". All wifi, bluetooth, wimax, gps, fm,
4738 0 The "airplane mode" button does nothing.
4739 1 The "airplane mode" button toggles between everything
4741 2 The "airplane mode" button toggles between everything
4751 ro [KNL] Mount root device read-only on boot
4754 on Mark read-only kernel memory as read-only (default).
4755 off Leave read-only kernel memory writable for debugging.
4760 debug-uart get routed to the D+ and D- pins of the usb
4782 rw [KNL] Mount root device read-write on boot
4784 S [KNL] Run init in single mode
4787 Set s390 IOTLB flushing mode
4824 to 10 seconds for built-in smp_call_function()
4831 that requesting even small non-zero numbers of
4838 The default of -1 specifies a number of kthreads
4843 test before initiating CPU-hotplug operations.
4847 CPU-hotplug operations. Specifying zero (which
4848 is the default) disables CPU-hotplug operations.
4854 Non-zero values are useful for automated tests.
4877 "wait" parameter. A value of -1 selects the
4878 default if all other weights are -1. However,
4880 value of -1 will instead select a weight of zero.
4885 non-zero "wait" parameter. See weight_single.
4898 non-zero "wait" parameter. See weight_single
4910 non-zero "wait" parameter. See weight_single
4917 0 -- disable. (may be 1 via CONFIG_CMDLINE="skew_tick=1"
4918 1 -- enable.
4929 0 -- disable.
4930 1 -- enable.
4936 0 -- disable.
4937 1 -- enable.
4940 serialnumber [BUGS=X86-32]
4945 simeth= [IA-64]
4979 memory cgroup sub-caches. 1 to enable, 0 to disable.
5012 smsc-ircc2.nopnp [HW] Don't use PNP to discover SMC devices
5013 smsc-ircc2.ircc_cfg= [HW] Device configuration I/O port
5014 smsc-ircc2.ircc_sir= [HW] SIR base I/O port
5015 smsc-ircc2.ircc_fir= [HW] FIR base I/O port
5016 smsc-ircc2.ircc_irq= [HW] IRQ line
5017 smsc-ircc2.ircc_dma= [HW] DMA channel
5018 smsc-ircc2.ircc_transceiver= [HW] Transceiver type:
5028 Default: -1 (no limit)
5031 [KNL] Should the soft-lockup detector generate panics.
5034 A value of 1 instructs the soft-lockup detector
5035 to panic the machine when a soft-lockup occurs. It is
5038 respective build-time switch to that functionality.
5041 [KNL] Should the soft-lockup detector generate
5046 See Documentation/admin-guide/laptops/sonypi.rst
5053 on - unconditionally enable, implies
5055 off - unconditionally disable, implies
5057 auto - kernel detects whether your CPU model is
5074 retpoline - replace indirect branches
5075 retpoline,generic - Retpolines
5076 retpoline,lfence - LFENCE; indirect branch
5077 retpoline,amd - alias for retpoline,lfence
5078 eibrs - enhanced IBRS
5079 eibrs,retpoline - enhanced IBRS + Retpolines
5080 eibrs,lfence - enhanced IBRS + LFENCE
5081 ibrs - use IBRS to protect kernel
5091 on - Unconditionally enable mitigations. Is
5094 off - Unconditionally disable mitigations. Is
5097 prctl - Indirect branch speculation is enabled,
5103 - Like "prctl" above, but only STIBP is
5109 - Same as "prctl" above, but all seccomp
5114 - Like "seccomp" above, but only STIBP is
5119 auto - Kernel selects the mitigation depending on
5151 on - Unconditionally disable Speculative Store Bypass
5152 off - Unconditionally enable Speculative Store Bypass
5153 auto - Kernel detects whether the CPU model contains an
5159 prctl - Control Speculative Store Bypass per thread
5163 seccomp - Same as "prctl" above, but all seccomp threads
5171 on,auto - On Power8 and Power9 insert a store-forwarding
5175 off - No action.
5192 off - not enabled
5194 warn - the kernel will emit rate limited warnings
5196 exception. This mode is the default on CPUs
5199 fatal - the kernel will send SIGBUS to applications
5203 firmware (i.e. not while executing in user mode)
5205 mode.
5211 Certain CPUs are vulnerable to an MDS-like
5229 grace-period sequence counter wrap for the
5230 srcu_data structure's ->srcu_gp_seq_needed field.
5252 force-on: Unconditionally enable mitigation for
5254 force-off: Unconditionally disable mitigation for
5271 stacktrace_filter=[function-list]
5273 will trace at boot up. function-list is a comma separated
5281 Set the STI (builtin display/keyboard on the HP-PARISC
5283 as the initial boot-console.
5284 See also comment in drivers/video/console/sticore.c.
5287 See comment in drivers/video/console/sticore.c.
5319 auto the server chooses an appropriate mode
5324 to global on non-NUMA machines)
5338 mode before resuming the system (see
5350 it if 0 is given (See Documentation/admin-guide/cgroup-v1/memory.rst)
5352 swiotlb= [ARM,IA-64,PPC,MIPS,X86]
5354 <int> -- Number of I/O TLB slabs
5355 force -- force using of bounce buffers even if they
5357 noforce -- Never use bounce buffers (for debugging)
5381 Ignore sysrq setting - this boot parameter will
5389 cache size. See Documentation/networking/ip-sysctl.rst
5395 Specify "mem" (for Suspend-to-RAM) or "standby" (for
5400 wakeup-capable RTC alarm.
5406 -1: disable all active trip points in all thermal zones
5410 -1: disable all critical trip points in all thermal zones
5421 -1: disable all passive trip points
5427 <deci-seconds>: poll all this frequency
5449 Prevent the CPU-hotplug component of torturing
5453 Dump the ftrace buffer at torture-test shutdown,
5457 with rotating-rust storage.
5473 trace_event=[event-list]
5475 to facilitate early boot debugging. The event-list is a
5479 trace_options=[option-list]
5481 The option-list is a comma delimited list of options
5531 See Documentation/admin-guide/mm/transhuge.rst
5539 high-resolution timer mode on older hardware, and in
5565 on - Enable TSX on the system. Although there are
5568 several previous speculation-related CVEs, and
5572 off - Disable TSX on the system. (Note that this
5580 auto - Disable TSX if X86_BUG_TAA is present,
5585 See Documentation/admin-guide/hw-vuln/tsx_async_abort.rst
5591 Similar to Micro-architectural Data Sampling (MDS)
5606 full - Enable TAA mitigation on vulnerable CPUs
5609 full,nosmt - Enable TAA mitigation and disable SMT on
5612 vulnerable to cross-thread TAA attacks.
5613 off - Unconditionally disable TAA mitigation
5615 On MDS-affected machines, tsx_async_abort=off can be
5627 Documentation/admin-guide/hw-vuln/tsx_async_abort.rst
5633 See also Documentation/input/devices/joystick-parport.rst
5635 udbg-immortal [PPC] When debugging early kernel crashes that
5641 Set number of hash buckets for UDP/UDP-Lite connections
5643 uhci-hcd.ignore_oc=
5645 Some badly-designed motherboards generate lots of
5656 (default -1 = authorized except for wireless USB,
5662 for newly-detected USB devices (default 2). This
5690 [USB] Specifies timeout for the initial 64-byte
5697 [USB] A list of quirk entries to augment the built-in
5700 VendorID:ProductID:Flags. The IDs are 4-digit hex
5702 will change the built-in quirk; setting it if it is
5707 a 255-byte read);
5711 Set-Interface requests);
5730 (bInterval-1).
5765 usb-storage.delay_use=
5769 usb-storage.quirks=
5771 override the built-in unusual_devs list. List
5774 and Product ID values (4-digit hex numbers) and
5776 to a common usb-storage quirk flag as follows:
5818 medium is write-protected).
5827 1 - undefined instruction events
5828 2 - system calls
5829 4 - invalid data aborts
5830 8 - SIGSEGV faults
5831 16 - SIGBUS faults
5847 vdso32= [X86] Control the 32-bit vDSO
5848 vdso32=1: enable 32-bit VDSO
5849 vdso32=0 or vdso32=2: disable 32-bit VDSO
5859 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
5861 vector= [IA-64,SMP]
5864 video= [FB] Frame buffer configuration
5867 video.brightness_switch_enabled= [0,1]
5869 generated by hotkey, video driver will adjust brightness
5871 the allocated input device; If set to 0, video driver
5892 vga= [BOOT,X86-32] Select a particular video mode
5894 Documentation/admin-guide/svga.rst.
5909 - Disable all of the above options
5930 vsyscall= [X86-64]
5933 code). Most statically-linked binaries and older
5957 see VGA-softcursor.txt. Default: 2 = underline.
5962 This is a 16-member array composed of values
5963 ranging from 0-255.
5968 This is a 16-member array composed of values
5969 ranging from 0-255.
5974 This is a 16-member array composed of values
5975 ranging from 0-255.
5980 Set system-wide default UTF-8 mode for all tty's.
5981 Default is 1, i.e. UTF-8 mode is enabled for all
5986 Format=<-1|0|1>
5987 Set system-wide default for whether a cursor
5988 is shown on new VTs. Default is -1,
5993 vt.italic= [VT] Default color for italic text; 0-15.
5996 vt.underline= [VT] Default color for underlined text; 0-15.
6000 see Documentation/watchdog/watchdog-parameters.rst
6001 or other driver-specific files in the
6027 that this also can be controlled per-workqueue for
6031 Per-cpu workqueues are generally preferred because
6033 locality; unfortunately, per-cpu workqueues tend to
6036 Enabling this makes the per-cpu workqueues which
6051 forces round-robin CPU selection to flush out
6056 x2apic_phys [X86-64,APIC] Use x2apic physical mode instead of
6057 default x2apic cluster mode on platforms
6060 x86_intel_mid_timer= [X86-32,APBT]
6066 xen_512gb_limit [KNL,X86-64,XEN]
6076 ide-disks -- unplug primary master IDE devices
6077 aux-ide-disks -- unplug non-primary-master IDE devices
6078 nics -- unplug network devices
6079 all -- unplug all emulated devices (NICs and IDE disks)
6080 unnecessary -- unplugging emulated devices is
6083 never -- do not unplug even if version check succeeds
6110 xen_timer_slop= [X86-64,XEN]
6135 preferred over the 2-level event handling, as it is
6156 allows the fallback firmware mode to be used:
6162 xhci-hcd.quirks [USB,KNL]
6174 is only called on a kernel crash. Default mode,
6175 i.e. either "ro" or "rw" mode, is controlled
6178 is called only on a kernel crash, mode is write,