Lines Matching +full:owl +full:- +full:mmc
5 force -- enable ACPI if default was off
6 on -- enable ACPI but allow fallback to DT [arm64,riscv64]
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
26 If set to vendor, prefer vendor-specific driver
58 Documentation/firmware-guide/acpi/debug.rst for more information about
116 Format: <byte> or <bitmap-list>
119 Disable auto-serialization of AML methods
122 auto-serialization feature.
140 Ignore the ACPI-based watchdog interface (WDAT) and let
161 acpi_osi=! # disable all built-in OS vendor
163 acpi_osi=!! # enable all built-in OS vendor
225 For broken nForce2 BIOS resulting in XT-PIC timer.
234 as soon as the kernel's real-mode entry point is called.
272 See Documentation/sound/alsa-configuration.rst
279 align_va_addr= [X86-64]
284 CPU-intensive style benchmark, and it can vary highly in
287 32: only for 32-bit processes
288 64: only for 64-bit processes
289 on: enable for both 32- and 64-bit processes
290 off: disable for both 32- and 64-bit processes
300 Allow execve() of 32-bit applications and setting of the
302 subset of the CPUs support 32-bit EL0. When this
303 parameter is present, the set of CPUs supporting 32-bit
305 and hot-unplug operations may be restricted.
307 See Documentation/arch/arm64/asymmetric-32bit.rst for more
310 amd_iommu= [HW,X86-64]
313 fullflush - Deprecated, equivalent to iommu.strict=1
314 off - do not initialize any AMD IOMMU found in
316 force_isolation - Force device isolation for all
321 force_enable - Force enable the IOMMU on platforms known
324 pgtbl_v1 - Use v1 page table for DMA-API (Default).
325 pgtbl_v2 - Use v2 page table for DMA-API.
326 irtcachedis - Disable Interrupt Remapping Table (IRT) caching.
328 amd_iommu_dump= [HW,X86-64]
334 amd_iommu_intr= [HW,X86-64]
337 legacy - Use legacy interrupt remapping mode.
338 vapic - Use virtual APIC mode, which allows IOMMU
340 This mode requires kvm-amd.avic=1.
377 Power management functions (SPARCstation-4/5 + deriv.)
379 Disable APC CPU standby support. SPARCstation-Fox does
380 not play well with APC CPU idle - disable it if you have
387 when initialising the APIC and IO-APIC components.
388 For X86-32, this can also be used to specify an APIC
411 0 -- disable.
412 1 -- enable.
415 arcrimi= [HW,NET] ARCnet - "RIM I" (entirely mem-mapped) cards
457 audit= [KNL] Enable the audit sub-system
459 0 | off - kernel audit is disabled and can not be
461 unset - kernel audit is initialized but disabled and
463 1 | on - kernel audit is initialized and partially
476 0 - Disable the BAU.
477 1 - Enable the BAU.
478 unset - Disable the BAU.
505 See Documentation/block/cmdline-partition.rst
518 See Documentation/admin-guide/bootconfig.rst
523 bttv.pll= See Documentation/admin-guide/media/bttv.rst
532 cachesize= [BUGS=X86-32] Override level 2 CPU cache size detection.
551 inclusive. See arch/mips/include/asm/pgtable-bits.h
561 - foo isn't auto-mounted if you mount all cgroups in
563 - foo isn't visible as an individually mountable
565 - if foo is an optional feature then the feature is
571 Specifying "pressure" disables per-cgroup pressure
585 nosocket -- Disable socket memory accounting.
586 nokmem -- Disable kernel memory accounting.
587 nobpf -- Disable BPF memory accounting.
592 0 -- check protection applied by kernel (includes
594 1 -- check protection requested by application.
606 numbers X. Note the Linux-specific bits are not necessarily
607 stable over kernel options, but the vendor-specific
627 force such clocks to be always-on nor does it reserve
631 information, see Documentation/driver-api/clk.rst.
633 clock= [BUGS=X86-32, HW] gettimeofday clocksource override.
650 [X86-32] pit,hpet,tsc;
657 [X86-64] hpet,tsc
663 architected timer so that code using WFE-based polling
683 clocksource-wdtest.holdoff= [KNL]
689 cma=nn[MG]@[start[MG][-end[MG]]]
700 Sets the size of kernel per-numa memory area for
702 per-numa CMA altogether. And If this option is not
704 With per-numa CMA enabled, DMA users on node nid will
731 com20020= [HW,NET] ARCnet - COM20020 chipset
735 com90io= [HW,NET] ARCnet - COM90xx chipset (IO-mapped buffers)
739 ARCnet - COM90xx chipset (memory-mapped buffers)
768 See Documentation/admin-guide/serial-console.rst for more
778 Start an early, polled-mode console on the 8250/16550
781 MMIO inter-register address stride is either 8-bit
782 (mmio), 16-bit (mmio16), or 32-bit (mmio32).
786 the h/w is not re-initialized.
813 syscall, or to executing "dmesg -S --raw" or to reading
837 disable the cpuidle sub-system
843 disable the cpufreq sub-system
851 [X86] Delay for N microsec between assert and de-assert
863 Run kdump after running panic-notifiers and dumping
876 [KNL, X86-64, ARM64, RISCV] Select a region under 4G first, and
879 See Documentation/admin-guide/kdump/kdump.rst for further details.
884 start-[end] where start and end are both
886 Documentation/admin-guide/kdump/kdump.rst for an example.
889 [KNL, X86-64, ARM64, RISCV] range could be above 4G.
896 [KNL, X86-64, ARM64, RISCV] range under 4G. When crashkernel=X,high
901 low memory is needed to make sure DMA buffers for 32-bit
905 --> x86: max(swiotlb_size_or_default() + 8MiB, 256MiB)
906 --> arm64: 128MiB
907 --> riscv: 128MiB
915 [KNL] Disable crypto self-tests
923 csdlock_debug= [KNL] Enable or disable debug add-ons of cross-CPU
938 See also Documentation/input/devices/joystick-parport.rst
951 [KNL] verbose locking self-tests
954 self-tests.
956 (no extra messages), setting it to -1 (all bits set)
957 will print _a_lot_ more information - normally only
992 Format: { on, no-mount, off }
994 no-mount:
999 get a -EPERM as result when trying to register files
1003 Default value is set in build-time with a kernel configuration.
1015 Documentation/admin-guide/mm/hugetlbpage.rst.
1029 delayacct [KNL] Enable per-task delay accounting
1124 entries for DMA-API debugging code. One entry is
1125 required per DMA-API allocation. Use this if the
1126 DMA-API debugging code disables itself because the
1130 With this option the DMA-API debugging driver
1148 Generic built-in EDID data sets are used, if one of
1153 available in Documentation/admin-guide/edid.rst. An EDID
1165 Control how the dt_cpu_ftrs device-tree binding is
1175 what data is available or for reverse-engineering.
1180 Documentation/admin-guide/dynamic-debug-howto.rst
1191 determined by stdout-path property in device tree's
1196 Start an early, polled-mode console on a Cadence
1207 Start an early, polled-mode console on the 8250/16550
1209 MMIO inter-register address stride is either 8-bit
1210 (mmio) or 32-bit (mmio32 or mmio32be).
1220 Start an early, polled-mode console on a pl011 serial
1224 the driver will use only 32-bit accessors to read/write
1233 Start an early, polled-mode console on a meson serial
1239 Start an early, polled-mode console on an msm serial
1245 Start an early, polled-mode console on an msm serial
1250 owl,<addr>
1251 Start an early, polled-mode console on a serial port
1257 Start an early, polled-mode console on a serial port
1263 Use RISC-V SBI (Supervisor Binary Interface) for early
1281 Start an early, polled-mode console on a lantiq serial
1295 Start an early, polled-mode, output-only console on the
1300 Start an early, polled-mode console on the
1306 Start an early, polled-mode console on a Qualcomm
1314 coherent non-x86 systems that use system memory for
1414 attribute is added to range 0x100000000-0x180000000 and
1415 0x10a0000000-0x1120000000.
1419 range 0x240000000-0x43fffffff.
1431 Documentation/admin-guide/acpi/ssdt-overlays.rst for details.
1448 elanfreq= [X86-32]
1456 See Documentation/admin-guide/kdump/kdump.rst for details.
1472 0 -- permissive (log only, no denials).
1473 1 -- enforcing (deny and log).
1505 See also Documentation/fault-injection/.
1509 See Documentation/admin-guide/sysctl/net.rst for
1513 See Documentation/admin-guide/blockdev/floppy.rst.
1516 [IA-64] Avoid check_sal_cache_flush which may hang on
1521 forcepae [X86-32]
1557 ftrace_filter=[function-list]
1559 tracer at boot up. function-list is a comma-separated
1564 ftrace_notrace=[function-list]
1566 function-list. This list can be changed at run time
1570 ftrace_graph_filter=[function-list]
1573 function-list is a comma-separated list of functions
1577 ftrace_graph_notrace=[function-list]
1579 function-list. This list is a comma-separated list of
1599 off -- Don't create device links from firmware info.
1600 permissive -- Create device links from firmware info
1603 on -- Create device links from firmware info and use it
1605 rpm -- Like "on", but also use to order runtime PM.
1618 strict -- Default. Continue waiting on consumers to
1620 timeout -- Give up waiting on consumers and call
1630 See also Documentation/input/devices/joystick-parport.rst
1634 gart_fix_e820= [X86-64] disable the fix e820 for K8 GART
1658 gcov_persist= [GCOV] When non-zero (default), profiling data for
1668 gpio-mockup.gpio_mockup_ranges
1671 gpio-mockup.gpio_mockup_named_lines
1703 against bounds-checking flaws in the kernel's
1709 [KNL] Should the hard-lockup detector generate
1715 for 64-bit NUMA, off otherwise.
1718 hcl= [IA-64] SGI's Hardware Graph compatibility layer
1725 corresponding firmware-first mode error processing
1735 during restoration read-only).
1761 hpet= [X86-32,HPET] option to control HPET usage
1778 number of pages to allocate per-node can be specified.
1779 See also Documentation/admin-guide/mm/hugetlbpage.rst.
1790 Documentation/admin-guide/mm/hugetlbpage.rst.
1801 boot-time allocation of gigantic hugepages is skipped.
1829 by the CONFIG_BOOTPARAM_HUNG_TASK_PANIC build-time
1835 hvc_iucv_allow= [S390] Comma-separated list of z/VM user IDs.
1852 (disabled by default, and as a pre-condition
1854 i8042.direct [HW] Put keyboard port into non-translated mode
1868 suspend-to-ram transitions, only during s2r
1892 -1 -- never invert brightness
1893 0 -- machine default
1894 1 -- force brightness inversion
1908 idle=nomwait: Disable mwait for CPU C-states
1936 legacy only accept legacy-NaN binaries, if supported
1938 2008 only accept 2008-NaN binaries, if supported
1947 'relaxed' straps the emulator for both legacy-NaN and
1948 2008-NaN, whereas 'strict' enables legacy-NaN only on
1957 Ignore loglevel setting - this will print /all/
2024 Formats: { "ima" | "ima-ng" | "ima-ngv2" | "ima-sig" |
2025 "ima-sigv2" }
2026 Default: "ima-ng"
2058 initcall_blacklist= [KNL] Do not execute a comma-separated list of
2059 initcall functions. Useful for debugging built-in
2104 0 -- basic integrity auditing messages. (Default)
2105 1 -- additional integrity auditing messages.
2133 could harm performance of some high-throughput
2142 1 to 9 specify maximum depth of C-state.
2151 algorithms for p-state selection. There are two
2152 P-state selection algorithms provided by
2155 on whether or not the hardware managed P-states
2162 used along with the hardware-managed P-states (HWP)
2166 in favor of acpi-cpufreq. Forcing the intel_pstate driver
2167 instead of acpi-cpufreq may disable platform features, such
2169 P-States information being indicated to OSPM and therefore
2172 or on platforms that use pcc-cpufreq instead of acpi-cpufreq.
2185 Allow per-logical-CPU P-State performance control limits using
2188 intremap= [X86-64, Intel-IOMMU]
2193 BIOS x2APIC opt-out request will be ignored
2217 0 - Try to allocate a 32-bit DMA address first, before
2219 1 - Allocate directly from the full usable range,
2221 greater than 32-bit addressing.
2225 0 - Lazy mode.
2231 1 - Strict mode.
2234 unset - Use value of CONFIG_IOMMU_DEFAULT_DMA_{LAZY,STRICT}.
2236 legacy driver-specific options takes precedence.
2241 0 - Use IOMMU translation for DMA.
2242 1 - Bypass the IOMMU for DMA.
2243 unset - Use value of CONFIG_IOMMU_DEFAULT_PASSTHROUGH.
2245 io7= [HW] IO7 for Marvel-based Alpha systems
2260 See Documentation/admin-guide/nfs/nfsroot.rst.
2284 Enables support for pseudo-NMIs in the kernel. This
2303 [Deprecated - use cpusets instead]
2304 Format: [flag-list,]<cpu-list>
2335 "number of CPUs in system - 1".
2361 The format of <cpu-list> is described above.
2365 ivrs_ioapic [HW,X86-64]
2366 Provide an override to the IOAPIC-ID<->DEVICE-ID
2370 For example, to map IOAPIC-ID decimal 10 to
2376 * To map IOAPIC-ID decimal 10 to PCI device 00:14.0
2379 * To map IOAPIC-ID decimal 10 to PCI segment 0x1 and
2383 ivrs_hpet [HW,X86-64]
2384 Provide an override to the HPET-ID<->DEVICE-ID
2388 For example, to map HPET-ID decimal 10 to
2394 * To map HPET-ID decimal 0 to PCI device 00:14.0
2397 * To map HPET-ID decimal 10 to PCI segment 0x1 and
2401 ivrs_acpihid [HW,X86-64]
2402 Provide an override to the ACPI-HID:UID<->DEVICE-ID
2406 For example, to map UART-HID:UID AMD0020:0 to
2412 * To map UART-HID:UID AMD0020:0 to PCI segment is 0,
2415 * To map UART-HID:UID AMD0020:0 to PCI segment 0x1 and
2436 kernelcore= [KNL,X86,IA-64,PPC]
2439 the kernel for non-movable allocations. The requested
2449 subsystem. Note that allocations like PTEs-from-HighMem
2457 for non-movable allocations and remaining memory is used
2468 gdb or control-c on the dbgp connection. When
2469 not using this parameter you use sysrq-g to break into
2474 or a supported polling keyboard driver (non-usb).
2501 Configure the RouterBoard 532 series on-chip
2504 kmemleak= [KNL] Boot-time kmemleak enable/disable
2510 kprobe_event=[probe-list]
2512 The probe-list is a semicolon delimited list of probe
2542 execution by eliminating the write-protection faults
2587 back to huge pages. If the value is a non-zero N, KVM will
2592 kvm-amd.nested= [KVM,AMD] Control nested virtualization feature in
2595 kvm-amd.npt= [KVM,AMD] Control KVM's use of Nested Page Tables,
2596 a.k.a. Two-Dimensional Page Tables. Default is 1
2600 kvm-arm.mode=
2605 nvhe: Standard nVHE-based mode, without support for
2608 protected: nVHE-based mode with support for guests whose
2611 nested: VHE-based mode with support for nested
2620 kvm-arm.vgic_v3_group0_trap=
2621 [KVM,ARM] Trap guest accesses to GICv3 group-0
2624 kvm-arm.vgic_v3_group1_trap=
2625 [KVM,ARM] Trap guest accesses to GICv3 group-1
2628 kvm-arm.vgic_v3_common_trap=
2632 kvm-arm.vgic_v4_enable=
2644 kvm-intel.ept= [KVM,Intel] Control KVM's use of Extended Page Tables,
2645 a.k.a. Two-Dimensional Page Tables. Default is 1
2649 kvm-intel.emulate_invalid_guest_state=
2651 state. Ignored if kvm-intel.enable_unrestricted_guest=1,
2657 kvm-intel.flexpriority=
2662 kvm-intel.nested=
2666 kvm-intel.unrestricted_guest=
2672 kvm-intel.vmentry_l1d_flush=[KVM,Intel] Mitigation for L1 Terminal Fault
2673 CVE-2018-3620.
2684 kvm-intel.vpid= [KVM,Intel] Control KVM's use of Virtual Processor
2704 on - enable the interface for the mitigation
2769 For details see: Documentation/admin-guide/hw-vuln/l1tf.rst
2775 lapic [X86-32,APIC] Enable the local APIC even if BIOS
2779 value for LAPIC timer one-shot implementation. Default
2802 libata.force= [LIBATA] Force configurations. The format is a comma-
2814 first fan-out link behind PMP device. It does not
2828 * Transfer mode: pio[0-7], mwdma[0-4] and udma[0-7].
2835 * rstonce: only attempt one reset during hot-unplug
2917 Set the number of locking read-acquisition kthreads.
2922 Set the number of locking write-acquisition kthreads.
2925 Set time (s) after boot for CPU-hotplug testing.
2928 Set time (s) between CPU-hotplug operations, or
2929 zero to disable CPU-hotplug testing.
2932 Set task-shuffle interval (jiffies). Shuffling
2933 tasks allows some CPUs to go into dyntick-idle
2938 is useful for hands-off automated testing.
2954 Run the write-side locktorture kthreads at
2955 sched_set_fifo() real-time priority.
2975 7 (KERN_DEBUG) debug-level messages
2985 logo.nologo [FB] Disables display of the built-in Linux logo.
3003 an IEEE 1284-compliant printer is attached; if
3009 time-consuming boot-time autodetection (up to 250 ms per
3030 machvec= [IA-64] Force the use of a particular machine-vector
3036 Example: machtype=lemote-yeeloong-2f-7inch
3038 max_addr=nn[KMG] [KNL,BOOT,IA-64] All physical memory greater
3051 (loop.max_loop) unconditionally pre-created at init time. The default
3054 devices can be requested on-demand with the
3055 /dev/loop-control interface.
3057 mce [X86-32] Machine Check Exception
3059 mce=option [X86-64] See Documentation/arch/x86/x86_64/boot-options.rst
3062 See Documentation/admin-guide/md.rst.
3069 Control mitigation for the Micro-architectural Data
3084 full - Enable MDS mitigation on vulnerable CPUs
3085 full,nosmt - Enable MDS mitigation and disable
3087 off - Unconditionally disable MDS mitigation
3089 On TAA-affected machines, mds=off can be prevented by
3098 For details see: Documentation/admin-guide/hw-vuln/mds.rst
3112 [ARC,MICROBLAZE] - the limit applies only to low memory,
3115 [ARM64] - only limits memory covered by the linear
3128 [ARM,MIPS] - override the memory layout reported by
3135 mem=nopentium [BUGS=X86-32] Disable usage of 4MB pages for kernel
3142 per-device physically contiguous DMA buffers.
3150 See Documentation/admin-guide/mm/memory-hotplug.rst.
3175 Example: Exclude memory from 0x18690000-0x1869ffff
3189 memmap=<size>%<offset>-<oldtype>+<newtype>
3191 from <oldtype> to <newtype>. If "-<oldtype>" is left
3206 repeatable BIOS-originated corruption always
3250 mem_encrypt= [X86-64] AMD Secure Memory Encryption (SME) control
3258 Refer to Documentation/virt/kvm/x86/amd-memory-encryption.rst
3262 s2idle - Suspend-To-Idle
3263 shallow - Power-On Suspend or equivalent (if supported)
3264 deep - Suspend-To-RAM or equivalent (if supported)
3265 See Documentation/admin-guide/pm/sleep-states.rst.
3267 mfgpt_irq= [IA-32] Specify the IRQ to use for the
3268 Multi-Function General Purpose Timers on AMD Geode
3271 mfgptfix [X86-32] Fix MFGPT timers on AMD Geode platforms when
3278 min_addr=nn[KMG] [KNL,BOOT,IA-64] All physical memory below this
3285 0 - The attached screen is the 3.5" TFT
3286 1 - The attached screen is the 7" TFT
3287 2 - The VGA Shield is attached (1024x768)
3291 b - Enable backlight. The TFT backlight pin will be
3295 c - Enable the s3c camera interface.
3296 t - Reserved for enabling touchscreen support. The
3300 https://repo.or.cz/w/linux-2.6/mini2440.git
3305 arch-independent options, each of which is an
3306 aggregation of existing arch-specific options.
3329 ssbd=force-off [ARM64]
3342 have other ways of avoiding SMT-based attacks.
3377 full - Enable mitigation on vulnerable CPUs
3379 full,nosmt - Enable mitigation and disable SMT on
3382 off - Unconditionally disable mitigation
3395 Documentation/admin-guide/hw-vuln/processor_mmio_stale_data.rst
3425 module_blacklist= [KNL] Do not load a comma-separated list of
3439 movablecore= [KNL,X86,IA-64,PPC]
3450 movable_node [KNL] Boot-time switch to make hotplugable memory
3457 Format: <name>,<region-number>,<size>,<offset>
3460 <name>,<region-number>[,<base>,<size>,<buswidth>,<altbuswidth>]
3468 See arch/arm/mach-s3c/mach-jive.c
3504 something different and driver-specific.
3537 [NFS] enable 64-bit inode numbers.
3538 If zero, the NFS client will fake up a 32-bit inode
3540 of returning the full 64-bit number.
3541 The default is to return 64-bit inode numbers.
3576 [NFS4] Specify an additional fixed unique ident-
3607 driver. A non-zero value sets the minimum interval
3612 server-to-server copies for which this server is
3624 server-to-server copy, knfsd temporarily mounts
3631 See Documentation/admin-guide/nfs/nfsroot.rst.
3633 nfsroot= [NFS] nfs root filesystem for disk-less boxes.
3634 See Documentation/admin-guide/nfs/nfsroot.rst.
3637 See Documentation/admin-guide/nfs/nfsroot.rst.
3641 NMI stack-backtrace request.
3650 0 - turn hardlockup detector in nmi_watchdog off
3651 1 - turn hardlockup detector in nmi_watchdog on
3663 no387 [BUGS=X86-32] Tells the kernel to use the 387 maths
3667 no4lvl [RISCV] Disable 4-level and 5-level paging modes. Forces
3668 kernel to use 3-level paging instead.
3670 no5lvl [X86-64,RISCV] Disable 5-level paging mode. Forces
3671 kernel to use 4-level paging instead.
3674 caches in the slab allocator. Saves per-node memory,
3711 no_entry_flush [PPC] Don't flush the L1-D cache when entering the kernel.
3713 noexec [IA-64]
3715 noexec32 [X86-64]
3716 This affects only 32-bit executables.
3717 noexec32=on: enable non-executable mappings (default)
3719 noexec32=off: disable non-executable mappings
3730 nofxsr [BUGS=X86-32] Disables x86 floating point extended
3732 legacy floating-point registers on task switch.
3734 nohalt [IA-64] Tells the kernel not to use the power saving
3736 power-consumption. On the positive side, it reduces
3737 interrupt wake-up latency, which may improve performance
3739 real-time systems.
3749 compared. However, if this command-line option is
3790 nointremap [X86-64, Intel-IOMMU] Do not enable interrupt
3792 [Deprecated - use intremap=off]
3794 nointroute [IA-64]
3800 noirqdebug [X86-32] Disables the code which attempts to detect and
3805 nojitter [IA-64] Disables jitter checking for ITC timers.
3812 no-kvmapf [X86,KVM] Disable paravirtualized asynchronous page
3815 no-kvmclock [X86,KVM] Disable paravirtualized KVM clock driver
3817 nolapic [X86-32,APIC] Do not enable or use the local APIC.
3819 nolapic_timer [X86-32,APIC] Do not use the local APIC timer.
3821 nomca [IA-64] Disable machine check abort handling
3823 nomce [X86-32] Disable Machine Check Exception
3825 nomfgpt [X86-32] Disable Multi-Function General Purpose
3831 not load if they could possibly displace the pre-
3834 perform display-mode changes or accelerated rendering.
3847 nopcid [X86-64] Disable the PCID cpu feature.
3852 nopti [X86-64]
3868 noreplace-smp [X86-32,SMP] Don't replace SMP instructions
3874 nosbagart [IA-64]
3876 no-scroll [VGA] Disables scrollback.
3877 This is required for the Braillex ib80-piezo Braille
3880 nosgx [X86-64,SGX] Disables Intel SGX kernel support.
3900 nosoftlockup [KNL] Disable the soft-lockup detector.
3905 nospectre_bhb [ARM64] Disable all mitigations for Spectre-BHB (branch
3918 no-steal-acc [X86,PV_OPS,ARM64,PPC/PSERIES] Disable paravirtualized
3928 [PPC] Don't flush the L1-D cache after accessing user data.
3941 no-vmw-sched-clock
3946 soft-lockup and NMI watchdog (hard-lockup).
3950 nox2apic [X86-64,APIC] Do not enable x2APIC mode.
3958 enabling legacy floating-point and sse state.
3984 nptcg= [IA-64] Override max number of concurrent global TLB
3993 n. So during boot up some boot time memory for per-cpu
3994 variables need be pre-allocated for later physical cpu
4009 See Documentation/admin-guide/sysctl/vm.rst for details.
4012 See Documentation/core-api/debugging-via-ohci1394.rst for more
4027 onenand.bdry= [HW,MTD] Flex-OneNAND Boundary Configuration
4031 boundary - index of last SLC block on Flex-OneNAND.
4033 lock - Configure if Flex-OneNAND boundary should be locked.
4047 running on a platform with a direct-mapped memory-side
4053 page_owner= [KNL] Boot-time page_owner enabling option.
4059 page_poison= [KNL] Boot-time parameter changing the state of
4086 See Documentation/admin-guide/tainted-kernels.rst for
4138 Set to non-zero to probe primary and secondary ISA
4144 Set to non-zero if a chip is present that snoops speed
4192 Set to non-zero to probe tertiary and further ISA
4208 Set to non-zero to probe QDI controllers. By default
4213 Set to non-zero to probe Winbond controllers. Use
4260 bios [X86-32] force use of PCI BIOS, don't access
4262 has a non-standard PCI host bridge.
4263 nobios [X86-32] disallow use of PCI BIOS, only direct
4269 data in IO port 0xCFC, both 32-bit).
4271 Mechanism 2 (IO port 0xCF8 is an 8-bit port for
4272 the function, IO port 0xCFA, also 8-bit, sets
4274 through ports 0xC000-0xCFFF).
4281 root domains (aka PCI segments, in ACPI-speak).
4289 disable the use of MSI interrupts system-wide.
4294 primary IO-APIC for bridges that cannot disable
4301 biosirq [X86-32] Use PCI BIOS calls to get the interrupt
4325 F0000h-100000h range.
4330 assign-busses [X86] Always assign all PCI bus
4351 <linux-pci@vger.kernel.org>.
4355 a bug to <linux-pci@vger.kernel.org>.
4367 bfsort Sort PCI devices into breadth-first order.
4370 nobfsort Don't sort PCI devices into breadth-first order.
4372 tuning and use the BIOS-configured MPS defaults.
4382 configuration allows peer-to-peer DMA between
4385 that hot-added devices will work.
4400 A PCI-PCI bridge can be specified if resource
4406 for 4096-byte alignment.
4408 end-to-end CRC checking). Only effective if
4439 noats [PCIE, Intel-IOMMU, AMD-IOMMU]
4475 dpc-native Use native PCIe service for DPC only. May
4492 Keep all power-domains already enabled by bootloader on,
4509 pirq= [SMP,APIC] Manual mp-table setup
4510 See Documentation/arch/x86/i386/IO-APIC.rst.
4514 See also Documentation/admin-guide/parport.rst.
4533 CONFIG_PNP_DEBUG_MESSAGES option). Change at run-time
4542 { on | off | curr | res | no-curr | no-res }
4582 none - Limited to cond_resched() calls
4583 voluntary - Limited to cond_resched() and might_sleep() calls
4584 full - Any section that isn't explicitly preempt disabled
4587 print-fatal-signals=
4593 coredump - etc.
4596 you might want to try "ulimit -i unlimited".
4608 or lockdep-detected issues (only if lock debug is on).
4617 on - unlimited logging to /dev/kmsg from userspace
4618 off - logging to /dev/kmsg disabled
4619 ratelimit - ratelimit the logging
4626 Limit processor to maximum C-state
4630 Ignore the _CST method to determine C-states,
4637 Param: "schedule" - profile schedule points.
4638 Param: "sleep" - profile D-state sleeping (millisecs).
4640 Param: "kvm" - profile VM exits.
4641 Param: <number> - step/bucket size as a power of 2 for
4670 pti= [X86-64] Control Page Table Isolation of user and
4675 on - unconditionally enable
4676 off - unconditionally disable
4677 auto - kernel detects whether your CPU model is
4683 [KNL] Number of legacy pty's. Overwrites compiled-in
4695 See Documentation/admin-guide/md.rst.
4698 See Documentation/admin-guide/blockdev/ramdisk.rst.
4717 cross-syscall address exposures. This is only
4723 ras=option[,option,...] [KNL] RAS-specific options
4729 rcu_nocbs[=cpu-list]
4734 enable the no-callback CPU mode, which prevents
4739 "p" for RCU-preempt, "s" for RCU-sched, and "g"
4743 and real-time workloads. It can also improve
4747 list of CPUs is set to no-callback mode from boot.
4751 no-callback mode from boot but the mode may be
4762 This improves the real-time response for the
4779 RCU grace-period cleanup.
4783 RCU grace-period initialization.
4787 RCU grace-period pre-initialization, that is,
4788 the propagation of recent CPU-hotplug changes up
4792 Set delay from grace-period initialization to
4805 soliciting quiescent-state help from
4817 Set the SCHED_FIFO priority of the RCU per-CPU
4820 and for the RCU grace-period kthreads (rcu_bh,
4822 set, valid values are 1-99 and the default is 1
4823 (the least-favored priority). Otherwise, when
4824 RCU_BOOST is not set, valid values are 0-99 and
4825 the default is zero (non-realtime operation).
4830 On callback-offloaded (rcu_nocbs) CPUs,
4833 use of the ->nocb_bypass list. However, in the
4834 common non-flooded case, RCU queues directly to
4835 the main ->cblist in order to avoid the extra
4836 overhead of the ->nocb_bypass list and its lock.
4838 a single jiffy, RCU pre-queues the callbacks into
4839 the ->nocb_bypass queue. The definition of "too
4848 batch limiting is re-enabled.
4852 RCU's force-quiescent-state scan will aggressively
4860 Set the page-cache refill delay (in milliseconds)
4861 in response to low-memory conditions. The range
4865 Set the shift-right count to use to compute
4866 the callback-invocation batch limit bl from
4873 Please note that this callback-invocation batch
4874 limit applies only to non-offloaded callback
4883 cache-to-cache transfer latencies.
4889 and for NUMA systems with large remote-access
4905 the wakeup overhead on the global grace-period
4907 each group's NOCB grace-period kthread.
4910 Cause the grace-period kthread to get an extra
4912 it should at force-quiescent-state time.
4925 this specifies an rcu_read_unlock()-time delay
4929 of RCU-protected pointers after the relevant
4939 per-CPU rcuc kthreads. Defaults to a non-zero
4949 grace-period primitives such as call_rcu().
4960 grace-period primitives.
4963 Set test-start holdoff period. The purpose of
4981 Test the double-argument variant of kfree_rcu().
4983 rcuscale.kfree_rcu_test_single, both the single-
4984 and double-argument variants are tested.
4987 Test the single-argument variant of kfree_rcu().
4989 rcuscale.kfree_rcu_test_double, both the single-
4990 and double-argument variants are tested.
5004 does not affect the data-collection interval,
5009 Set number of RCU readers. The value -1 selects
5011 "n" less than -1 selects N-n+1, where N is again
5012 the number of CPUs. For example, -2 selects N
5013 (the number of CPUs), -3 selects N+1, and so on.
5014 A value of "n" less than or equal to -N selects
5027 complete. This is useful for hands-off automated
5034 Write-side holdoff between grace periods,
5039 Additional write-side holdoff between grace
5057 for RCU grace-period forward-progress testing
5064 Specify the fraction of a CPU-stall-warning
5065 period to do tight-loop forward-progress testing.
5069 forward-progress tests.
5073 need_resched() during tight-loop forward-progress
5077 Use conditional/asynchronous update-side
5081 Use expedited update-side primitives, if available.
5084 Use normal (non-expedited) asynchronous
5085 update-side primitives, if available.
5088 Use normal (non-expedited) synchronous
5089 update-side primitives, if available. If all
5093 they are all non-zero.
5101 Leak an RCU-protected pointer out of the reader.
5116 Set number of RCU callback-offload togglers.
5121 callback-offload toggling attempts.
5124 Set number of RCU readers. The value -1 selects
5125 N-1, where N is the number of CPUs. A value
5126 "n" less than -1 selects N-n-2, where N is again
5127 the number of CPUs. For example, -2 selects N
5128 (the number of CPUs), -3 selects N+1, and so on.
5131 Enable debug-object double-call_rcu() testing.
5134 Set time (s) after boot for CPU-hotplug testing.
5137 Set time (jiffies) between CPU-hotplug operations,
5138 or zero to disable CPU-hotplug testing.
5141 Set the number of read-then-exit kthreads used
5143 task-exit processing.
5146 The number of times in a given read-then-exit
5147 episode that a set of read-then-exit kthreads
5152 read-then-exit testing episodes.
5155 Set task-shuffle interval (s). Shuffling tasks
5156 allows some CPUs to go into dyntick-idle mode
5161 is useful for hands-off automated testing.
5170 any other stall-related activity. Note that
5176 in scheduling-while-atomic splats.
5189 grace-period kthread to test RCU CPU stall
5215 Test RCU's dyntick-idle handling. See also the
5264 Use expedited grace-period primitives, for
5268 real-time latency, and degrade energy efficiency.
5272 Use only normal grace-period primitives,
5275 real-time latency, CPU utilization, and
5277 increased grace-period latency. This parameter
5284 only normal grace-period primitives. No effect
5290 post-boot attempt at an expedited RCU grace
5291 period to instead use normal non-expedited
5292 grace-period processing.
5300 set to the default value of -1.
5303 Set the minimum number of callback-queuing-time
5304 lock-contention events per jiffy required to
5305 cause the RCU Tasks flavors to switch to per-CPU
5308 the default value of -1.
5313 of -1 allows this to be automatically (and
5321 number avoids disturbing real-time workloads,
5326 cancel laziness on that CPU. Use -1 to disable
5336 only printed prior to the stall-warning message
5392 force - Override the decision by the kernel to hide the
5420 Set test-start holdoff period. The purpose of
5429 but the default has already reduced the per-pass
5434 Set number of readers. The default value of -1
5443 Set the read-side critical-section duration,
5447 Specify the read-protection implementation to test.
5466 See Documentation/admin-guide/cgroup-v1/cpusets.rst.
5474 reservetop= [X86-32]
5491 See Documentation/power/swsusp-and-swap-files.rst
5498 (e.g. USB and MMC devices).
5506 AMD-based UNRET and IBPB mitigations alone do not stop
5508 sibling threads. For that reason, STIBP is used on pro-
5512 off - no mitigation
5513 auto - automatically select a migitation
5514 auto,nosmt - automatically select a mitigation,
5518 ibpb - On AMD, mitigate short speculation
5523 ibpb,nosmt - Like "ibpb" above but will disable SMT
5527 unret - Force enable untrained return thunks,
5528 only effective on AMD f15h-f17h based
5530 unret,nosmt - Like unret, but will disable SMT when STIBP
5565 ro [KNL] Mount root device read-only on boot
5568 on Mark read-only kernel memory as read-only (default).
5569 off Leave read-only kernel memory writable for debugging.
5570 full Mark read-only kernel memory and aliases as read-only
5576 debug-uart get routed to the D+ and D- pins of the usb
5582 block/early-lookup.c for details.
5596 (e.g. USB and MMC devices).
5607 rw [KNL] Mount root device read-write on boot
5659 to 10 seconds for built-in smp_call_function()
5666 that requesting even small non-zero numbers of
5673 The default of -1 specifies a number of kthreads
5678 test before initiating CPU-hotplug operations.
5682 CPU-hotplug operations. Specifying zero (which
5683 is the default) disables CPU-hotplug operations.
5689 Non-zero values are useful for automated tests.
5712 "wait" parameter. A value of -1 selects the
5713 default if all other weights are -1. However,
5715 value of -1 will instead select a weight of zero.
5720 non-zero "wait" parameter. See weight_single.
5733 non-zero "wait" parameter. See weight_single
5745 non-zero "wait" parameter. See weight_single
5752 0 -- disable. (may be 1 via CONFIG_CMDLINE="skew_tick=1"
5753 1 -- enable.
5764 0 -- disable.
5765 1 -- enable.
5768 serialnumber [BUGS=X86-32]
5770 sev=option[,option...] [X86-64] See Documentation/arch/x86/x86_64/boot-options.rst
5778 to set it to "all" by meaning -- no limit here.
5784 simeth= [IA-64]
5859 using the csdlock_debug- kernel parameter.
5861 smsc-ircc2.nopnp [HW] Don't use PNP to discover SMC devices
5862 smsc-ircc2.ircc_cfg= [HW] Device configuration I/O port
5863 smsc-ircc2.ircc_sir= [HW] SIR base I/O port
5864 smsc-ircc2.ircc_fir= [HW] FIR base I/O port
5865 smsc-ircc2.ircc_irq= [HW] IRQ line
5866 smsc-ircc2.ircc_dma= [HW] DMA channel
5867 smsc-ircc2.ircc_transceiver= [HW] Transceiver type:
5877 Default: -1 (no limit)
5880 [KNL] Should the soft-lockup detector generate panics.
5883 A value of 1 instructs the soft-lockup detector
5884 to panic the machine when a soft-lockup occurs. It is
5887 respective build-time switch to that functionality.
5890 [KNL] Should the soft-lockup detector generate
5895 See Documentation/admin-guide/laptops/sonypi.rst
5902 on - unconditionally enable, implies
5904 off - unconditionally disable, implies
5906 auto - kernel detects whether your CPU model is
5923 retpoline - replace indirect branches
5924 retpoline,generic - Retpolines
5925 retpoline,lfence - LFENCE; indirect branch
5926 retpoline,amd - alias for retpoline,lfence
5927 eibrs - Enhanced/Auto IBRS
5928 eibrs,retpoline - Enhanced/Auto IBRS + Retpolines
5929 eibrs,lfence - Enhanced/Auto IBRS + LFENCE
5930 ibrs - use IBRS to protect kernel
5940 on - Unconditionally enable mitigations. Is
5943 off - Unconditionally disable mitigations. Is
5946 prctl - Indirect branch speculation is enabled,
5952 - Like "prctl" above, but only STIBP is
5958 - Same as "prctl" above, but all seccomp
5963 - Like "seccomp" above, but only STIBP is
5968 auto - Kernel selects the mitigation depending on
5979 off - Disable mitigation
5980 microcode - Enable microcode mitigation only
5981 safe-ret - Enable sw-only safe RET mitigation (default)
5982 ibpb - Enable mitigation by issuing IBPB on
5984 ibpb-vmexit - Issue IBPB only on VMEXIT
5985 (cloud-specific mitigation)
6010 on - Unconditionally disable Speculative Store Bypass
6011 off - Unconditionally enable Speculative Store Bypass
6012 auto - Kernel detects whether the CPU model contains an
6018 prctl - Control Speculative Store Bypass per thread
6022 seccomp - Same as "prctl" above, but all seccomp threads
6030 on,auto - On Power8 and Power9 insert a store-forwarding
6034 off - No action.
6053 off - not enabled
6055 warn - the kernel will emit rate-limited warnings
6063 fatal - the kernel will send SIGBUS to applications
6068 ratelimit:N -
6088 Certain CPUs are vulnerable to an MDS-like
6108 This kernel-boot parameter defaults to 128,
6109 but takes effect only when the low-order four
6126 instead of the compile-time CONFIG_NR_CPUS.
6130 grace-period sequence counter wrap for the
6131 srcu_data structure's ->srcu_gp_seq_needed field.
6146 Specifies the number of no-delay instances
6153 Specifies the per-grace-period phase, number of
6154 non-sleeping polls of readers. Beyond this limit,
6160 Specifies number of microseconds of non-sleeping
6161 delay between each non-sleeping poll of readers.
6164 Specifies the number of update-side contention
6169 set for contention-based conversions to occur.
6179 force-on: Unconditionally enable mitigation for
6181 force-off: Unconditionally disable mitigation for
6204 stacktrace_filter=[function-list]
6206 will trace at boot up. function-list is a comma-separated
6214 Set the STI (builtin display/keyboard on the HP-PARISC
6216 as the initial boot-console.
6276 to global on non-NUMA machines)
6299 swiotlb= [ARM,IA-64,PPC,MIPS,X86]
6301 <int> -- Number of I/O TLB slabs
6302 <int> -- Second integer after comma. Number of swiotlb
6305 force -- force using of bounce buffers even if they
6307 noforce -- Never use bounce buffers (for debugging)
6322 Ignore sysrq setting - this boot parameter will
6330 cache size. See Documentation/networking/ip-sysctl.rst
6337 Specify "mem" (for Suspend-to-RAM) or "standby" (for
6342 wakeup-capable RTC alarm.
6348 -1: disable all active trip points in all thermal zones
6352 -1: disable all critical trip points in all thermal zones
6359 -1: disable all passive trip points
6365 <deci-seconds>: poll all this frequency
6387 Prevent the CPU-hotplug component of torturing
6391 Dump the ftrace buffer at torture-test shutdown,
6395 with rotating-rust storage.
6400 disables verbose-printk() sleeping.
6403 Duration of each verbose-printk() sleep in jiffies.
6421 https://trustedcomputinggroup.org/resource/pc-client-platform-tpm-profile-ptp-specification/
6459 local - Use the per CPU time stamp counter
6463 global - Event time stamps are synchronize across
6466 counter - Simple counting of events (1, 2, ..)
6470 uptime - Use jiffies as the time stamp.
6471 perf - Use the same clock that perf uses.
6472 mono - Use ktime_get_mono_fast_ns() for time stamps.
6473 mono_raw - Use ktime_get_raw_fast_ns() for time
6475 boot - Use ktime_get_boot_fast_ns() for time stamps.
6479 trace_event=[event-list]
6481 to facilitate early boot debugging. The event-list is a
6482 comma-separated list of trace events to enable. See
6485 trace_instance=[instance-info]
6505 trace_options=[option-list]
6507 The option-list is a comma delimited list of options
6521 trace_trigger=[trigger-list]
6558 See Documentation/admin-guide/mm/transhuge.rst
6566 - "tpm"
6567 - "tee"
6568 - "caam"
6578 - "kernel"
6579 - the same value as trusted.source: "tpm" or "tee"
6580 - "default"
6589 high-resolution timer mode on older hardware, and in
6625 on - Enable TSX on the system. Although there are
6628 several previous speculation-related CVEs, and
6632 off - Disable TSX on the system. (Note that this
6640 auto - Disable TSX if X86_BUG_TAA is present,
6645 See Documentation/admin-guide/hw-vuln/tsx_async_abort.rst
6651 Similar to Micro-architectural Data Sampling (MDS)
6666 full - Enable TAA mitigation on vulnerable CPUs
6669 full,nosmt - Enable TAA mitigation and disable SMT on
6672 vulnerable to cross-thread TAA attacks.
6673 off - Unconditionally disable TAA mitigation
6675 On MDS-affected machines, tsx_async_abort=off can be
6687 Documentation/admin-guide/hw-vuln/tsx_async_abort.rst
6693 See also Documentation/input/devices/joystick-parport.rst
6695 udbg-immortal [PPC] When debugging early kernel crashes that
6701 Set number of hash buckets for UDP/UDP-Lite connections
6703 uhci-hcd.ignore_oc=
6705 Some badly-designed motherboards generate lots of
6714 unwind_debug [X86-64]
6722 (default -1 = authorized (same as 1),
6728 for newly-detected USB devices (default 2). This
6756 [USB] Specifies timeout for the initial 64-byte
6763 [USB] A list of quirk entries to augment the built-in
6766 VendorID:ProductID:Flags. The IDs are 4-digit hex
6768 will change the built-in quirk; setting it if it is
6773 a 255-byte read);
6777 Set-Interface requests);
6796 (bInterval-1).
6831 usb-storage.delay_use=
6835 usb-storage.quirks=
6837 override the built-in unusual_devs list. List
6840 and Product ID values (4-digit hex numbers) and
6842 to a common usb-storage quirk flag as follows:
6884 medium is write-protected).
6893 1 - undefined instruction events
6894 2 - system calls
6895 4 - invalid data aborts
6896 8 - SIGSEGV faults
6897 16 - SIGBUS faults
6913 vdso32= [X86] Control the 32-bit vDSO
6914 vdso32=1: enable 32-bit VDSO
6915 vdso32=0 or vdso32=2: disable 32-bit VDSO
6925 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
6927 vector= [IA-64,SMP]
6959 vga= [BOOT,X86-32] Select a particular video mode
6961 Documentation/admin-guide/svga.rst.
6976 - Disable all of the above options
6997 vsyscall= [X86-64]
7000 code). Most statically-linked binaries and older
7024 see VGA-softcursor.txt. Default: 2 = underline.
7029 This is a 16-member array composed of values
7030 ranging from 0-255.
7035 This is a 16-member array composed of values
7036 ranging from 0-255.
7041 This is a 16-member array composed of values
7042 ranging from 0-255.
7047 Set system-wide default UTF-8 mode for all tty's.
7048 Default is 1, i.e. UTF-8 mode is enabled for all
7053 Format=<-1|0|1>
7054 Set system-wide default for whether a cursor
7055 is shown on new VTs. Default is -1,
7060 vt.italic= [VT] Default color for italic text; 0-15.
7063 vt.underline= [VT] Default color for underlined text; 0-15.
7067 see Documentation/watchdog/watchdog-parameters.rst
7068 or other driver-specific files in the
7082 Format: <cpu-list>
7096 Per-cpu work items which run for longer than this
7099 them from noticeably delaying other per-cpu work
7108 Per-cpu workqueues are generally preferred because
7110 locality; unfortunately, per-cpu workqueues tend to
7113 Enabling this makes the per-cpu workqueues which
7127 Documentation/core-api/workqueue.rst.
7140 forces round-robin CPU selection to flush out
7148 on - Enable writecombine, use WUC for ioremap_wc()
7149 off - Disable writecombine, use SUC for ioremap_wc()
7151 x2apic_phys [X86-64,APIC] Use x2apic physical mode instead of
7155 xen_512gb_limit [KNL,X86-64,XEN]
7165 ide-disks -- unplug primary master IDE devices
7166 aux-ide-disks -- unplug non-primary-master IDE devices
7167 nics -- unplug network devices
7168 all -- unplug all emulated devices (NICs and IDE disks)
7169 unnecessary -- unplugging emulated devices is
7172 never -- do not unplug even if version check succeeds
7180 Select whether to always use non-faulting (safe) MSR
7205 xen_timer_slop= [X86-64,XEN]
7230 preferred over the 2-level event handling, as it is
7247 xive.store-eoi=off [PPC]
7253 xhci-hcd.quirks [USB,KNL]