Lines Matching +full:msm +full:- +full:iommu +full:- +full:v1
16 force -- enable ACPI if default was off
17 on -- enable ACPI but allow fallback to DT [arm64,riscv64]
18 off -- disable ACPI if default was on
19 noirq -- do not use ACPI for IRQ routing
20 strict -- Be less tolerant of platforms that are not
22 rsdt -- prefer RSDT over (default) XSDT
23 copy_dsdt -- copy DSDT to memory
24 nocmcff -- Disable firmware first mode for corrected
28 nospcr -- disable console in ACPI SPCR table as
45 If set to vendor, prefer vendor-specific driver
77 Documentation/firmware-guide/acpi/debug.rst for more information about
135 Format: <byte> or <bitmap-list>
138 Disable auto-serialization of AML methods
141 auto-serialization feature.
159 Ignore the ACPI-based watchdog interface (WDAT) and let
180 acpi_osi=! # disable all built-in OS vendor
182 acpi_osi=!! # enable all built-in OS vendor
244 For broken nForce2 BIOS resulting in XT-PIC timer.
253 as soon as the kernel's real-mode entry point is called.
291 See Documentation/sound/alsa-configuration.rst
298 align_va_addr= [X86-64]
303 CPU-intensive style benchmark, and it can vary highly in
306 32: only for 32-bit processes
307 64: only for 64-bit processes
308 on: enable for both 32- and 64-bit processes
309 off: disable for both 32- and 64-bit processes
319 Allow execve() of 32-bit applications and setting of the
321 subset of the CPUs support 32-bit EL0. When this
322 parameter is present, the set of CPUs supporting 32-bit
324 and hot-unplug operations may be restricted.
326 See Documentation/arch/arm64/asymmetric-32bit.rst for more
329 amd_iommu= [HW,X86-64]
330 Pass parameters to the AMD IOMMU driver in the system.
332 fullflush - Deprecated, equivalent to iommu.strict=1
333 off - do not initialize any AMD IOMMU found in
335 force_isolation - Force device isolation for all
336 devices. The IOMMU driver is not
339 does not override iommu=pt
340 force_enable - Force enable the IOMMU on platforms known
341 to be buggy with IOMMU enabled. Use this
343 pgtbl_v1 - Use v1 page table for DMA-API (Default).
344 pgtbl_v2 - Use v2 page table for DMA-API.
345 irtcachedis - Disable Interrupt Remapping Table (IRT) caching.
346 nohugepages - Limit page-sizes used for v1 page-tables
348 v2_pgsizes_only - Limit page-sizes used for v1 page-tables
352 amd_iommu_dump= [HW,X86-64]
353 Enable AMD IOMMU driver option to dump the ACPI table
354 for AMD IOMMU. With this option enabled, AMD IOMMU
355 driver will print ACPI tables for AMD IOMMU during
356 IOMMU initialization.
358 amd_iommu_intr= [HW,X86-64]
359 Specifies one of the following AMD IOMMU interrupt
361 legacy - Use legacy interrupt remapping mode.
362 vapic - Use virtual APIC mode, which allows IOMMU
364 This mode requires kvm-amd.avic=1.
365 (Default when IOMMU HW support is present.)
393 Disable amd-pstate preferred core.
406 Power management functions (SPARCstation-4/5 + deriv.)
408 Disable APC CPU standby support. SPARCstation-Fox does
409 not play well with APC CPU idle - disable it if you have
412 apic [APIC,X86-64] Use IO-APIC. Default.
418 when initialising the APIC and IO-APIC components.
442 0 -- disable.
443 1 -- enable.
446 arcrimi= [HW,NET] ARCnet - "RIM I" (entirely mem-mapped) cards
497 audit= [KNL] Enable the audit sub-system
499 0 | off - kernel audit is disabled and can not be
501 unset - kernel audit is initialized but disabled and
503 1 | on - kernel audit is initialized and partially
516 0 - Disable the BAU.
517 1 - Enable the BAU.
518 unset - Disable the BAU.
557 See Documentation/block/cmdline-partition.rst
571 See Documentation/admin-guide/bootconfig.rst
576 bttv.pll= See Documentation/admin-guide/media/bttv.rst
585 cachesize= [BUGS=X86-32] Override level 2 CPU cache size detection.
604 inclusive. See arch/mips/include/asm/pgtable-bits.h
614 - foo isn't auto-mounted if you mount all cgroups in
616 - foo isn't visible as an individually mountable
618 - if foo is an optional feature then the feature is
624 Specifying "pressure" disables per-cgroup pressure
627 cgroup_no_v1= [KNL] Disable cgroup controllers and named hierarchies in v1
630 Like cgroup_disable, but only applies to cgroup v1;
634 all v1 hierarchies.
642 nosocket -- Disable socket memory accounting.
643 nokmem -- Disable kernel memory accounting.
644 nobpf -- Disable BPF memory accounting.
649 0 -- check protection applied by kernel (includes
651 1 -- check protection requested by application.
663 numbers X. Note the Linux-specific bits are not necessarily
664 stable over kernel options, but the vendor-specific
684 force such clocks to be always-on nor does it reserve
688 information, see Documentation/driver-api/clk.rst.
690 clock= [BUGS=X86-32, HW] gettimeofday clocksource override.
707 [X86-32] pit,hpet,tsc;
714 [X86-64] hpet,tsc
720 architected timer so that code using WFE-based polling
734 clocksource-wdtest.holdoff= [KNL]
740 cma=nn[MG]@[start[MG][-end[MG]]]
751 Sets the size of kernel per-numa memory area for
753 per-numa CMA altogether. And If this option is not
755 With per-numa CMA enabled, DMA users on node nid will
782 com20020= [HW,NET] ARCnet - COM20020 chipset
786 com90io= [HW,NET] ARCnet - COM90xx chipset (IO-mapped buffers)
790 ARCnet - COM90xx chipset (memory-mapped buffers)
819 See Documentation/admin-guide/serial-console.rst for more
834 $ ls -d /sys/bus/serial-base/devices/*:*.*/tty/*
835 /sys/bus/serial-base/devices/00:04:0.0/tty/ttyS0
848 Start an early, polled-mode console on the 8250/16550
851 MMIO inter-register address stride is either 8-bit
852 (mmio), 16-bit (mmio16), or 32-bit (mmio32).
856 the h/w is not re-initialized.
883 syscall, or to executing "dmesg -S --raw" or to reading
907 disable the cpuidle sub-system
913 disable the cpufreq sub-system
921 [X86,EARLY] Delay for N microsec between assert and de-assert
942 like Hyper-V, PowerPC (fadump) and AMD SEV-SNP.
950 [KNL, X86-64, ARM64, RISCV, LoongArch] Select a region
953 See Documentation/admin-guide/kdump/kdump.rst for further details.
958 start-[end] where start and end are both
960 Documentation/admin-guide/kdump/kdump.rst for an example.
963 [KNL, X86-64, ARM64, RISCV, LoongArch] range could be
971 [KNL, X86-64, ARM64, RISCV, LoongArch] range under 4G.
977 for 32-bit devices won't run out. Kernel would try to allocate
980 --> x86: max(swiotlb_size_or_default() + 8MiB, 256MiB)
981 --> arm64: 128MiB
982 --> riscv: 128MiB
983 --> loongarch: 128MiB
991 [KNL] Disable crypto self-tests
999 csdlock_debug= [KNL] Enable or disable debug add-ons of cross-CPU
1014 See also Documentation/input/devices/joystick-parport.rst
1027 [KNL] verbose locking self-tests
1030 self-tests.
1032 (no extra messages), setting it to -1 (all bits set)
1033 will print _a_lot_ more information - normally only
1068 Format: { on, no-mount, off }
1070 no-mount:
1075 get a -EPERM as result when trying to register files
1079 Default value is set in build-time with a kernel configuration.
1091 Documentation/admin-guide/mm/hugetlbpage.rst.
1105 delayacct [KNL] Enable per-task delay accounting
1191 entries for DMA-API debugging code. One entry is
1192 required per DMA-API allocation. Use this if the
1193 DMA-API debugging code disables itself because the
1197 With this option the DMA-API debugging driver
1221 Documentation/admin-guide/hw-vuln/reg-file-data-sampling.rst
1246 Control how the dt_cpu_ftrs device-tree binding is
1256 what data is available or for reverse-engineering.
1261 Documentation/admin-guide/dynamic-debug-howto.rst
1272 determined by stdout-path property in device tree's
1277 Start an early, polled-mode console on a Cadence
1288 Start an early, polled-mode console on the 8250/16550
1290 MMIO inter-register address stride is either 8-bit
1291 (mmio) or 32-bit (mmio32 or mmio32be).
1301 Start an early, polled-mode console on a pl011 serial
1305 the driver will use only 32-bit accessors to read/write
1314 Start an early, polled-mode console on a meson serial
1320 Start an early, polled-mode console on an msm serial
1326 Start an early, polled-mode console on an msm serial
1332 Start an early, polled-mode console on a serial port
1338 Start an early, polled-mode console on a serial port
1344 Use RISC-V SBI (Supervisor Binary Interface) for early
1362 Start an early, polled-mode console on a lantiq serial
1376 Start an early, polled-mode, output-only console on the
1381 Start an early, polled-mode console on the
1387 Start an early, polled-mode console on a Qualcomm
1395 coherent non-x86 systems that use system memory for
1498 Documentation/admin-guide/acpi/ssdt-overlays.rst for details.
1515 elanfreq= [X86-32]
1523 See Documentation/admin-guide/kdump/kdump.rst for details.
1539 0 -- permissive (log only, no denials).
1540 1 -- enforcing (deny and log).
1573 See also Documentation/fault-injection/.
1577 See Documentation/admin-guide/sysctl/net.rst for
1581 See Documentation/admin-guide/blockdev/floppy.rst.
1583 forcepae [X86-32]
1590 fred= [X86-64]
1641 ftrace_filter=[function-list]
1643 tracer at boot up. function-list is a comma-separated
1648 ftrace_notrace=[function-list]
1650 function-list. This list can be changed at run time
1654 ftrace_graph_filter=[function-list]
1657 function-list is a comma-separated list of functions
1661 ftrace_graph_notrace=[function-list]
1663 function-list. This list is a comma-separated list of
1683 off -- Don't create device links from firmware info.
1684 permissive -- Create device links from firmware info
1687 on -- Create device links from firmware info and use it
1689 rpm -- Like "on", but also use to order runtime PM.
1702 strict -- Default. Continue waiting on consumers to
1704 timeout -- Give up waiting on consumers and call
1714 See also Documentation/input/devices/joystick-parport.rst
1718 gart_fix_e820= [X86-64,EARLY] disable the fix e820 for K8 GART
1744 gcov_persist= [GCOV] When non-zero (default), profiling data for
1754 gpio-mockup.gpio_mockup_ranges
1757 gpio-mockup.gpio_mockup_named_lines
1789 against bounds-checking flaws in the kernel's
1797 [KNL] Should the hard-lockup detector generate
1803 for 64-bit NUMA, off otherwise.
1811 corresponding firmware-first mode error processing
1821 during restoration read-only).
1865 hpet= [X86-32,HPET] option to control HPET usage
1882 number of pages to allocate per-node can be specified.
1883 See also Documentation/admin-guide/mm/hugetlbpage.rst.
1894 Documentation/admin-guide/mm/hugetlbpage.rst.
1904 Note that this parameter only applies to non-gigantic huge pages.
1914 boot-time allocation of gigantic hugepages is skipped.
1949 by the CONFIG_BOOTPARAM_HUNG_TASK_PANIC build-time
1955 hvc_iucv_allow= [S390] Comma-separated list of z/VM user IDs.
1977 Set device-properties for ACPI-enumerated I2C-attached
1978 touchscreen, to e.g. fix coordinates of upside-down
1986 Omit "=<val>" entirely Set a boolean device-property
1987 Unsigned number Set a u32 device-property
1988 Anything else Set a string device-property
1991 i2c_touchscreen_props=GDIX1001:touchscreen-inverted-x:
1992 touchscreen-inverted-y
1994 i2c_touchscreen_props=MSSL1680:touchscreen-size-x=1920:
1995 touchscreen-size-y=1080:touchscreen-inverted-y:
1996 firmware-name=gsl1680-vendor-model.fw:silead,home-button
2001 (disabled by default, and as a pre-condition
2003 i8042.direct [HW] Put keyboard port into non-translated mode
2017 suspend-to-ram transitions, only during s2r
2041 -1 -- never invert brightness
2042 0 -- machine default
2043 1 -- force brightness inversion
2045 ia32_emulation= [X86-64]
2047 When true, allows loading 32-bit programs and executing 32-bit
2072 idle=nomwait: Disable mwait for CPU C-states
2100 legacy only accept legacy-NaN binaries, if supported
2102 2008 only accept 2008-NaN binaries, if supported
2113 'relaxed' straps the emulator for both legacy-NaN and
2114 2008-NaN, whereas 'strict' enables legacy-NaN only on
2123 Ignore loglevel setting - this will print /all/
2190 Formats: { "ima" | "ima-ng" | "ima-ngv2" | "ima-sig" |
2191 "ima-sigv2" }
2192 Default: "ima-ng"
2225 stuff: Deploy RSB-fill mitigation when retpoline is
2230 Documentation/admin-guide/hw-vuln/indirect-target-selection.rst
2241 initcall_blacklist= [KNL] Do not execute a comma-separated list of
2242 initcall functions. Useful for debugging built-in
2287 0 -- basic integrity auditing messages. (Default)
2288 1 -- additional integrity auditing messages.
2290 intel_iommu= [DMAR] Intel IOMMU driver (DMAR) option
2292 Enable intel iommu driver.
2294 Disable intel iommu driver.
2302 Deprecated, equivalent to iommu.strict=1.
2304 By default, super page will be supported if Intel IOMMU
2308 Enable the Intel IOMMU scalable mode if the hardware
2312 Disallow use of the Intel IOMMU scalable mode.
2314 Do not force the Intel IOMMU enabled under tboot.
2315 By default, tboot will force Intel IOMMU on, which
2316 could harm performance of some high-throughput
2325 1 to 9 specify maximum depth of C-state.
2334 algorithms for p-state selection. There are two
2335 P-state selection algorithms provided by
2338 on whether or not the hardware managed P-states
2345 used along with the hardware-managed P-states (HWP)
2349 in favor of acpi-cpufreq. Forcing the intel_pstate driver
2350 instead of acpi-cpufreq may disable platform features, such
2352 P-States information being indicated to OSPM and therefore
2355 or on platforms that use pcc-cpufreq instead of acpi-cpufreq.
2368 Allow per-logical-CPU P-State performance control limits using
2371 Do not enable capacity-aware scheduling (CAS) on
2374 intremap= [X86-64,Intel-IOMMU,EARLY]
2379 BIOS x2APIC opt-out request will be ignored
2388 iommu= [X86,EARLY]
2391 Don't initialize and use any kind of IOMMU.
2394 Force the use of the hardware IOMMU even when
2399 Don't force hardware IOMMU usage when it is not
2411 of an available hardware IOMMU.
2419 Disable IOMMU bypass, using IOMMU for PCI devices.
2422 AMD Gart HW IOMMU-specific options:
2428 Overwrite iommu off workarounds for specific chipsets
2431 Flush IOMMU on each allocation (default).
2434 Don't use IOMMU fullflush.
2441 Do scatter-gather (SG) merging. Implies "force"
2445 Don't do scatter-gather (SG) merging.
2448 Ask the IOMMU not to touch the aperture for AGP.
2454 Always panic when IOMMU overflows.
2456 iommu.forcedac= [ARM64,X86,EARLY] Control IOVA allocation for PCI devices.
2458 0 - Try to allocate a 32-bit DMA address first, before
2460 1 - Allocate directly from the full usable range,
2462 greater than 32-bit addressing.
2464 iommu.strict= [ARM64,X86,S390,EARLY] Configure TLB invalidation behaviour
2466 0 - Lazy mode.
2471 the relevant IOMMU driver.
2472 1 - Strict mode.
2473 DMA unmap operations invalidate IOMMU hardware TLBs
2475 unset - Use value of CONFIG_IOMMU_DEFAULT_DMA_{LAZY,STRICT}.
2477 legacy driver-specific options takes precedence.
2479 iommu.passthrough=
2480 [ARM64,X86,EARLY] Configure DMA to bypass the IOMMU by default.
2482 0 - Use IOMMU translation for DMA.
2483 1 - Bypass the IOMMU for DMA.
2484 unset - Use value of CONFIG_IOMMU_DEFAULT_PASSTHROUGH.
2486 io7= [HW] IO7 for Marvel-based Alpha systems
2501 See Documentation/admin-guide/nfs/nfsroot.rst.
2537 Enables support for pseudo-NMIs in the kernel. This
2556 [Deprecated - use cpusets instead]
2557 Format: [flag-list,]<cpu-list>
2590 "number of CPUs in system - 1".
2616 The format of <cpu-list> is described above.
2620 ivrs_ioapic [HW,X86-64]
2621 Provide an override to the IOAPIC-ID<->DEVICE-ID
2625 For example, to map IOAPIC-ID decimal 10 to
2631 * To map IOAPIC-ID decimal 10 to PCI device 00:14.0
2634 * To map IOAPIC-ID decimal 10 to PCI segment 0x1 and
2638 ivrs_hpet [HW,X86-64]
2639 Provide an override to the HPET-ID<->DEVICE-ID
2643 For example, to map HPET-ID decimal 10 to
2649 * To map HPET-ID decimal 0 to PCI device 00:14.0
2652 * To map HPET-ID decimal 10 to PCI segment 0x1 and
2656 ivrs_acpihid [HW,X86-64]
2657 Provide an override to the ACPI-HID:UID<->DEVICE-ID
2661 For example, to map UART-HID:UID AMD0020:0 to
2667 * To map UART-HID:UID AMD0020:0 to PCI segment is 0,
2670 * To map UART-HID:UID AMD0020:0 to PCI segment 0x1 and
2694 the kernel for non-movable allocations. The requested
2704 subsystem. Note that allocations like PTEs-from-HighMem
2712 for non-movable allocations and remaining memory is used
2723 gdb or control-c on the dbgp connection. When
2724 not using this parameter you use sysrq-g to break into
2729 or a supported polling keyboard driver (non-usb).
2758 "0" | "off" | "n" - kexec handover is disabled
2759 "1" | "on" | "y" - kexec handover is enabled
2765 ranges that can only be used for non-kernel
2776 parameter defines the size of additional per-node
2781 Configure the RouterBoard 532 series on-chip
2784 kmemleak= [KNL,EARLY] Boot-time kmemleak enable/disable
2790 kprobe_event=[probe-list]
2792 The probe-list is a semicolon delimited list of probe
2822 execution by eliminating the write-protection faults
2849 virtualization on-demand when creating and destroying
2857 is that doing so may interfere with using out-of-tree
2884 back to huge pages. If the value is a non-zero N, KVM will
2889 kvm-amd.nested= [KVM,AMD] Control nested virtualization feature in
2892 kvm-amd.npt= [KVM,AMD] Control KVM's use of Nested Page Tables,
2893 a.k.a. Two-Dimensional Page Tables. Default is 1
2897 kvm-arm.mode=
2903 nvhe: Standard nVHE-based mode, without support for
2910 nested: VHE-based mode with support for nested
2918 command-line.
2922 kvm-arm.vgic_v3_group0_trap=
2923 [KVM,ARM,EARLY] Trap guest accesses to GICv3 group-0
2926 kvm-arm.vgic_v3_group1_trap=
2927 [KVM,ARM,EARLY] Trap guest accesses to GICv3 group-1
2930 kvm-arm.vgic_v3_common_trap=
2934 kvm-arm.vgic_v4_enable=
2938 kvm-arm.wfe_trap_policy=
2947 kvm-arm.wfi_trap_policy=
2964 kvm-intel.ept= [KVM,Intel] Control KVM's use of Extended Page Tables,
2965 a.k.a. Two-Dimensional Page Tables. Default is 1
2969 kvm-intel.emulate_invalid_guest_state=
2971 state. Ignored if kvm-intel.enable_unrestricted_guest=1,
2977 kvm-intel.flexpriority=
2982 kvm-intel.nested=
2986 kvm-intel.unrestricted_guest=
2992 kvm-intel.vmentry_l1d_flush=[KVM,Intel] Mitigation for L1 Terminal Fault
2993 CVE-2018-3620.
3004 kvm-intel.vpid= [KVM,Intel] Control KVM's use of Virtual Processor
3024 on - enable the interface for the mitigation
3089 For details see: Documentation/admin-guide/hw-vuln/l1tf.rst
3095 lapic [X86-32,APIC,EARLY] Enable the local APIC even if BIOS
3099 value for LAPIC timer one-shot implementation. Default
3122 libata.force= [LIBATA] Force configurations. The format is a comma-
3134 first fan-out link behind PMP device. It does not
3148 * Transfer mode: pio[0-7], mwdma[0-4] and udma[0-7].
3155 * rstonce: only attempt one reset during hot-unplug
3198 * external: Mark port as external (hotplug-capable).
3252 Specify the number of self-propagating call_rcu()
3260 occasional long-duration lock hold time. Defaults
3271 Set the number of locking read-acquisition kthreads.
3276 Set the number of locking write-acquisition kthreads.
3279 Set time (s) after boot for CPU-hotplug testing.
3282 Set time (s) between CPU-hotplug operations, or
3283 zero to disable CPU-hotplug testing.
3286 Do periodic testing of real-time lock priority
3291 non-real-time spinlocks, due to their disabling
3292 of preemption. Note that non-realtime mutexes
3305 Set task-shuffle interval (jiffies). Shuffling
3306 tasks allows some CPUs to go into dyntick-idle
3311 is useful for hands-off automated testing.
3330 Run the write-side locktorture kthreads at
3331 sched_set_fifo() real-time priority.
3349 7 (KERN_DEBUG) debug-level messages
3361 logo.nologo [FB] Disables display of the built-in Linux logo.
3379 an IEEE 1284-compliant printer is attached; if
3385 time-consuming boot-time autodetection (up to 250 ms per
3405 Example: machtype=lemote-yeeloong-2f-7inch
3417 (loop.max_loop) unconditionally pre-created at init time. The default
3420 devices can be requested on-demand with the
3421 /dev/loop-control interface.
3423 mce= [X86-{32,64}]
3460 do not opt-in to Local MCE delivery. Use legacy method
3481 don't overwrite the bios-set CMCI threshold. This boot
3490 force-enable recoverable machine check code paths
3496 See Documentation/admin-guide/md.rst.
3503 Control mitigation for the Micro-architectural Data
3518 full - Enable MDS mitigation on vulnerable CPUs
3519 full,nosmt - Enable MDS mitigation and disable
3521 off - Unconditionally disable MDS mitigation
3523 On TAA-affected machines, mds=off can be prevented by
3532 For details see: Documentation/admin-guide/hw-vuln/mds.rst
3547 [ARC,MICROBLAZE] - the limit applies only to low memory,
3550 [ARM64] - only limits memory covered by the linear
3563 [ARM,MIPS,EARLY] - override the memory layout
3570 mem=nopentium [BUGS=X86-32] Disable usage of 4MB pages for kernel
3577 per-device physically contiguous DMA buffers.
3585 See Documentation/admin-guide/mm/memory-hotplug.rst.
3610 Example: Exclude memory from 0x18690000-0x1869ffff
3624 memmap=<size>%<offset>-<oldtype>+<newtype>
3626 from <oldtype> to <newtype>. If "-<oldtype>" is left
3641 repeatable BIOS-originated corruption always
3685 mem_encrypt= [X86-64] AMD Secure Memory Encryption (SME) control
3691 Refer to Documentation/virt/kvm/x86/amd-memory-encryption.rst
3695 s2idle - Suspend-To-Idle
3696 shallow - Power-On Suspend or equivalent (if supported)
3697 deep - Suspend-To-RAM or equivalent (if supported)
3698 See Documentation/admin-guide/pm/sleep-states.rst.
3700 mfgptfix [X86-32] Fix MFGPT timers on AMD Geode platforms when
3716 0 - The attached screen is the 3.5" TFT
3717 1 - The attached screen is the 7" TFT
3718 2 - The VGA Shield is attached (1024x768)
3722 b - Enable backlight. The TFT backlight pin will be
3726 c - Enable the s3c camera interface.
3727 t - Reserved for enabling touchscreen support. The
3731 https://repo.or.cz/w/linux-2.6/mini2440.git
3736 arch-independent options, each of which is an
3737 aggregation of existing arch-specific options.
3767 ssbd=force-off [ARM64]
3780 have other ways of avoiding SMT-based attacks.
3815 full - Enable mitigation on vulnerable CPUs
3817 full,nosmt - Enable mitigation and disable SMT on
3820 off - Unconditionally disable mitigation
3833 Documentation/admin-guide/hw-vuln/processor_mmio_stale_data.rst
3863 module_blacklist= [KNL] Do not load a comma-separated list of
3888 movable_node [KNL,EARLY] Boot-time switch to make hotplugable memory
3895 Format: <name>,<region-number>,<size>,<offset>
3898 <name>,<region-number>[,<base>,<size>,<buswidth>,<altbuswidth>]
3937 something different and driver-specific.
3977 [NFS] enable 64-bit inode numbers.
3978 If zero, the NFS client will fake up a 32-bit inode
3980 of returning the full 64-bit number.
3981 The default is to return 64-bit inode numbers.
4016 [NFS4] Specify an additional fixed unique ident-
4047 driver. A non-zero value sets the minimum interval
4052 server-to-server copies for which this server is
4064 server-to-server copy, knfsd temporarily mounts
4071 See Documentation/admin-guide/nfs/nfsroot.rst.
4073 nfsroot= [NFS] nfs root filesystem for disk-less boxes.
4074 See Documentation/admin-guide/nfs/nfsroot.rst.
4077 See Documentation/admin-guide/nfs/nfsroot.rst.
4081 NMI stack-backtrace request.
4090 0 - turn hardlockup detector in nmi_watchdog off
4091 1 - turn hardlockup detector in nmi_watchdog on
4092 rNNN - configure the watchdog with raw perf event 0xNNN
4105 no387 [BUGS=X86-32] Tells the kernel to use the 387 maths
4109 no4lvl [RISCV,EARLY] Disable 4-level and 5-level paging modes.
4110 Forces kernel to use 3-level paging instead.
4112 no5lvl [X86-64,RISCV,EARLY] Disable 5-level paging mode. Forces
4113 kernel to use 4-level paging instead.
4148 no_entry_flush [PPC,EARLY] Don't flush the L1-D cache when entering the kernel.
4150 noexec32 [X86-64]
4151 This affects only 32-bit executables.
4152 noexec32=on: enable non-executable mappings (default)
4154 noexec32=off: disable non-executable mappings
4165 nofxsr [BUGS=X86-32] Disables x86 floating point extended
4167 legacy floating-point registers on task switch.
4180 compared. However, if this command-line option is
4223 nointremap [X86-64,Intel-IOMMU,EARLY] Do not enable interrupt
4225 [Deprecated - use intremap=off]
4231 noirqdebug [X86-32] Disables the code which attempts to detect and
4241 no-kvmapf [X86,KVM,EARLY] Disable paravirtualized asynchronous page
4244 no-kvmclock [X86,KVM,EARLY] Disable paravirtualized KVM clock driver
4246 nolapic [X86-32,APIC,EARLY] Do not enable or use the local APIC.
4248 nolapic_timer [X86-32,APIC,EARLY] Do not use the local APIC timer.
4250 nomce [X86-32] Disable Machine Check Exception
4252 nomfgpt [X86-32] Disable Multi-Function General Purpose
4258 not load if they could possibly displace the pre-
4261 perform display-mode changes or accelerated rendering.
4274 nopcid [X86-64,EARLY] Disable the PCID cpu feature.
4279 nopti [X86-64,EARLY]
4295 noreplace-smp [X86-32,SMP] Don't replace SMP instructions
4301 no-scroll [VGA] Disables scrollback.
4302 This is required for the Braillex ib80-piezo Braille
4305 nosgx [X86-64,SGX,EARLY] Disables Intel SGX kernel support.
4325 nosoftlockup [KNL] Disable the soft-lockup detector.
4331 nospectre_bhb [ARM64,EARLY] Disable all mitigations for Spectre-BHB (branch
4344 no-steal-acc [X86,PV_OPS,ARM64,PPC/PSERIES,RISCV,LOONGARCH,EARLY]
4351 timer IRQ sources, i.e., the IO-APIC timer. This can
4356 [PPC,EARLY] Don't flush the L1-D cache after accessing user data.
4369 no-vmw-sched-clock
4374 soft-lockup and NMI watchdog (hard-lockup).
4378 nox2apic [X86-64,APIC,EARLY] Do not enable x2APIC mode.
4386 enabling legacy floating-point and sse state.
4408 n. So during boot up some boot time memory for per-cpu
4409 variables need be pre-allocated for later physical cpu
4436 soft-reserved memory partitioning.
4445 See Documentation/admin-guide/sysctl/vm.rst for details.
4448 See Documentation/core-api/debugging-via-ohci1394.rst for more
4463 onenand.bdry= [HW,MTD] Flex-OneNAND Boundary Configuration
4467 boundary - index of last SLC block on Flex-OneNAND.
4469 lock - Configure if Flex-OneNAND boundary should be locked.
4488 page_owner= [KNL,EARLY] Boot-time page_owner enabling option.
4494 page_poison= [KNL,EARLY] Boot-time parameter changing the state of
4522 See Documentation/admin-guide/tainted-kernels.rst for
4575 Set to non-zero to probe primary and secondary ISA
4581 Set to non-zero if a chip is present that snoops speed
4629 Set to non-zero to probe tertiary and further ISA
4645 Set to non-zero to probe QDI controllers. By default
4650 Set to non-zero to probe Winbond controllers. Use
4697 bios [X86-32] force use of PCI BIOS, don't access
4699 has a non-standard PCI host bridge.
4700 nobios [X86-32] disallow use of PCI BIOS, only direct
4706 data in IO port 0xCFC, both 32-bit).
4708 Mechanism 2 (IO port 0xCF8 is an 8-bit port for
4709 the function, IO port 0xCFA, also 8-bit, sets
4711 through ports 0xC000-0xCFFF).
4718 root domains (aka PCI segments, in ACPI-speak).
4726 disable the use of MSI interrupts system-wide.
4731 primary IO-APIC for bridges that cannot disable
4738 biosirq [X86-32] Use PCI BIOS calls to get the interrupt
4762 F0000h-100000h range.
4767 assign-busses [X86] Always assign all PCI bus
4788 <linux-pci@vger.kernel.org>.
4792 a bug to <linux-pci@vger.kernel.org>.
4803 and some IOMMU drivers will not work.
4804 bfsort Sort PCI devices into breadth-first order.
4807 nobfsort Don't sort PCI devices into breadth-first order.
4809 tuning and use the BIOS-configured MPS defaults.
4819 configuration allows peer-to-peer DMA between
4822 that hot-added devices will work.
4837 A PCI-PCI bridge can be specified if resource
4843 for 4096-byte alignment.
4845 end-to-end CRC checking). Only effective if
4876 noats [PCIE, Intel-IOMMU, AMD-IOMMU]
4877 do not use PCIe ATS (and IOMMU device IOTLB).
4895 may put more devices in an IOMMU group.
4907 bit-0 : ACS Source Validation
4908 bit-1 : ACS Translation Blocking
4909 bit-2 : ACS P2P Request Redirect
4910 bit-3 : ACS P2P Completion Redirect
4911 bit-4 : ACS Upstream Forwarding
4912 bit-5 : ACS P2P Egress Control
4913 bit-6 : ACS Direct Translated P2P
4923 Validation unchanged from whatever power-up
4927 and may put more devices in an IOMMU group.
4935 system-wide.
4949 dpc-native Use native PCIe service for DPC only. May
4966 Keep all power-domains already enabled by bootloader on,
4984 pirq= [SMP,APIC] Manual mp-table setup
4985 See Documentation/arch/x86/i386/IO-APIC.rst.
4989 See also Documentation/admin-guide/parport.rst.
5008 CONFIG_PNP_DEBUG_MESSAGES option). Change at run-time
5017 { on | off | curr | res | no-curr | no-res }
5062 none - Limited to cond_resched() calls
5063 voluntary - Limited to cond_resched() and might_sleep() calls
5064 full - Any section that isn't explicitly preempt disabled
5068 lazy - Scheduler controlled. Similar to full but instead
5074 print-fatal-signals=
5080 coredump - etc.
5083 you might want to try "ulimit -i unlimited".
5095 or lockdep-detected issues (only if lock debug is on).
5103 Allows storing messages from non-panic CPUs into
5105 flushed to consoles by the panic-CPU on
5106 a best-effort basis.
5112 on - unlimited logging to /dev/kmsg from userspace
5113 off - logging to /dev/kmsg disabled
5114 ratelimit - ratelimit the logging
5125 - 'always': traditional behavior always allows mem overrides.
5126 - 'ptrace': only allow mem overrides for active ptracers.
5127 - 'never': never allow mem overrides.
5131 Limit processor to maximum C-state
5135 Ignore the _CST method to determine C-states,
5142 Param: "schedule" - profile schedule points.
5143 Param: "kvm" - profile VM exits.
5144 Param: <number> - step/bucket size as a power of 2 for
5175 pti= [X86-64] Control Page Table Isolation of user and
5180 on - unconditionally enable
5181 off - unconditionally disable
5182 auto - kernel detects whether your CPU model is
5188 [KNL] Number of legacy pty's. Overwrites compiled-in
5200 See Documentation/admin-guide/md.rst.
5203 See Documentation/admin-guide/blockdev/ramdisk.rst.
5222 cross-syscall address exposures. This is only
5228 ras=option[,option,...] [KNL] RAS-specific options
5234 rcu_nocbs[=cpu-list]
5239 enable the no-callback CPU mode, which prevents
5244 "p" for RCU-preempt, "s" for RCU-sched, and "g"
5248 and real-time workloads. It can also improve
5252 list of CPUs is set to no-callback mode from boot.
5256 no-callback mode from boot but the mode may be
5267 This improves the real-time response for the
5278 Do only a one-line RCU CPU stall warning when
5279 there is an ongoing too-long CSD-lock wait.
5285 If triggered before the RCU grace-period machinery
5295 RCU grace-period cleanup.
5299 RCU grace-period initialization.
5303 RCU grace-period pre-initialization, that is,
5304 the propagation of recent CPU-hotplug changes up
5308 Set delay from grace-period initialization to
5321 soliciting quiescent-state help from
5333 Set the SCHED_FIFO priority of the RCU per-CPU
5336 and for the RCU grace-period kthreads (rcu_bh,
5338 set, valid values are 1-99 and the default is 1
5339 (the least-favored priority). Otherwise, when
5340 RCU_BOOST is not set, valid values are 0-99 and
5341 the default is zero (non-realtime operation).
5346 On callback-offloaded (rcu_nocbs) CPUs,
5349 use of the ->nocb_bypass list. However, in the
5350 common non-flooded case, RCU queues directly to
5351 the main ->cblist in order to avoid the extra
5352 overhead of the ->nocb_bypass list and its lock.
5354 a single jiffy, RCU pre-queues the callbacks into
5355 the ->nocb_bypass queue. The definition of "too
5359 On callback-offloaded (rcu_nocbs) CPUs, avoid
5372 batch limiting is re-enabled.
5376 RCU's force-quiescent-state scan will aggressively
5384 Set the page-cache refill delay (in milliseconds)
5385 in response to low-memory conditions. The range
5389 Set the shift-right count to use to compute
5390 the callback-invocation batch limit bl from
5397 Please note that this callback-invocation batch
5398 limit applies only to non-offloaded callback
5407 cache-to-cache transfer latencies.
5413 and for NUMA systems with large remote-access
5429 the wakeup overhead on the global grace-period
5431 each group's NOCB grace-period kthread.
5434 Cause the grace-period kthread to get an extra
5436 it should at force-quiescent-state time.
5449 this specifies an rcu_read_unlock()-time delay
5453 of RCU-protected pointers after the relevant
5463 per-CPU rcuc kthreads. Defaults to a non-zero
5492 grace-period primitives such as call_rcu().
5503 grace-period primitives.
5506 Set test-start holdoff period. The purpose of
5524 Test the double-argument variant of kfree_rcu().
5526 rcuscale.kfree_rcu_test_single, both the single-
5527 and double-argument variants are tested.
5530 Test the single-argument variant of kfree_rcu().
5532 rcuscale.kfree_rcu_test_double, both the single-
5533 and double-argument variants are tested.
5547 does not affect the data-collection interval,
5552 Set number of RCU readers. The value -1 selects
5554 "n" less than -1 selects N-n+1, where N is again
5555 the number of CPUs. For example, -2 selects N
5556 (the number of CPUs), -3 selects N+1, and so on.
5557 A value of "n" less than or equal to -N selects
5570 complete. This is useful for hands-off automated
5577 Write-side holdoff between grace periods,
5582 Additional write-side holdoff between grace
5600 for RCU grace-period forward-progress testing
5607 Specify the fraction of a CPU-stall-warning
5608 period to do tight-loop forward-progress testing.
5612 forward-progress tests.
5616 need_resched() during tight-loop forward-progress
5620 Use conditional/asynchronous update-side
5621 normal-grace-period primitives, if available.
5624 Use conditional/asynchronous update-side
5625 expedited-grace-period primitives, if available.
5628 Use conditional/asynchronous update-side
5629 normal-grace-period primitives that also take
5634 Use conditional/asynchronous update-side
5635 expedited-grace-period primitives that also take
5659 Use expedited update-side primitives, if available.
5662 Use normal (non-expedited) asynchronous
5663 update-side primitives, if available.
5666 Use polled update-side normal-grace-period
5670 Use polled update-side expedited-grace-period
5674 Use polled update-side normal-grace-period
5679 Use polled update-side expedited-grace-period
5703 Use normal (non-expedited) synchronous
5704 update-side primitives, if available. If all
5708 they are all non-zero.
5711 Enable grace-period wrap lag testing. Setting
5716 Set the value for grace-period wrap lag during
5731 the grace-period wrap lag will be set to the
5741 Leak an RCU-protected pointer out of the reader.
5756 Set number of RCU callback-offload togglers.
5761 callback-offload toggling attempts.
5764 Set number of RCU readers. The value -1 selects
5765 N-1, where N is the number of CPUs. A value
5766 "n" less than -1 selects N-n-2, where N is again
5767 the number of CPUs. For example, -2 selects N
5768 (the number of CPUs), -3 selects N+1, and so on.
5771 Enable debug-object double-call_rcu() testing.
5774 Set time (s) after boot for CPU-hotplug testing.
5777 Set time (jiffies) between CPU-hotplug operations,
5778 or zero to disable CPU-hotplug testing.
5782 by a high-priority FIFO real-time task. Set to
5791 second) between preemptions by a high-priority
5792 FIFO real-time task. This delay is mediated
5797 The number of times in a given read-then-exit
5798 episode that a set of read-then-exit kthreads
5803 read-then-exit testing episodes.
5808 are entered from low-order bit up, and are
5810 0x1 bit is normal readers, 0x2 NMI-safe readers,
5811 and 0x4 light-weight readers.
5814 Set task-shuffle interval (s). Shuffling tasks
5815 allows some CPUs to go into dyntick-idle mode
5820 is useful for hands-off automated testing.
5829 any other stall-related activity. Note that
5835 in scheduling-while-atomic splats.
5854 grace-period kthread to test RCU CPU stall
5878 of RCU priority-boost testing. Defaults to zero,
5885 Test RCU's dyntick-idle handling. See also the
5940 Use expedited grace-period primitives, for
5944 real-time latency, and degrade energy efficiency.
5948 Use only normal grace-period primitives,
5951 real-time latency, CPU utilization, and
5953 increased grace-period latency. This parameter
5960 only normal grace-period primitives. No effect
5966 post-boot attempt at an expedited RCU grace
5967 period to instead use normal non-expedited
5968 grace-period processing.
5976 set to the default value of -1.
5979 Set the minimum number of callback-queuing-time
5980 lock-contention events per jiffy required to
5981 cause the RCU Tasks flavors to switch to per-CPU
5984 the default value of -1.
5989 of -1 allows this to be automatically (and
5997 number avoids disturbing real-time workloads,
6002 cancel laziness on that CPU. Use -1 to disable
6012 only printed prior to the stall-warning message
6060 force - Override the decision by the kernel to hide the
6099 There are some built-in platform specific "quirks"
6100 - you may see: "reboot: <name> series board detected.
6104 built-in quirk table, and use the generic default
6137 Set test-start holdoff period. The purpose of
6152 but the default has already reduced the per-pass
6157 Set number of readers. The default value of -1
6166 Set the read-side critical-section duration,
6170 Specify the read-protection implementation to test.
6196 See Documentation/admin-guide/cgroup-v1/cpusets.rst.
6226 reservetop= [X86-32,EARLY]
6243 See Documentation/power/swsusp-and-swap-files.rst
6259 AMD-based UNRET and IBPB mitigations alone do not stop
6261 sibling threads. For that reason, STIBP is used on pro-
6265 off - no mitigation
6266 auto - automatically select a migitation
6267 auto,nosmt - automatically select a mitigation,
6271 ibpb - On AMD, mitigate short speculation
6276 ibpb,nosmt - Like "ibpb" above but will disable SMT
6280 unret - Force enable untrained return thunks,
6281 only effective on AMD f15h-f17h based
6283 unret,nosmt - Like unret, but will disable SMT when STIBP
6315 ro [KNL] Mount root device read-only on boot
6318 on Mark read-only kernel memory as read-only (default).
6319 off Leave read-only kernel memory writable for debugging.
6320 full Mark read-only kernel memory and aliases as read-only
6327 debug-uart get routed to the D+ and D- pins of the usb
6333 block/early-lookup.c for details.
6363 rw [KNL] Mount root device read-write on boot
6373 iommu.strict=1.
6377 accessible through the DMA and IOMMU APIs as a decimal
6417 to 10 seconds for built-in smp_call_function()
6424 that requesting even small non-zero numbers of
6431 The default of -1 specifies a number of kthreads
6436 test before initiating CPU-hotplug operations.
6440 CPU-hotplug operations. Specifying zero (which
6441 is the default) disables CPU-hotplug operations.
6447 Non-zero values are useful for automated tests.
6470 "wait" parameter. A value of -1 selects the
6471 default if all other weights are -1. However,
6473 value of -1 will instead select a weight of zero.
6478 non-zero "wait" parameter. See weight_single.
6491 non-zero "wait" parameter. See weight_single
6503 non-zero "wait" parameter. See weight_single
6514 0 -- disable. (may be 1 via CONFIG_CMDLINE="skew_tick=1"
6515 1 -- enable.
6526 0 -- disable.
6527 1 -- enable.
6530 serialnumber [BUGS=X86-32]
6532 sev=option[,option...] [X86-64]
6538 Do not enable SEV-SNP (applies to host/hypervisor
6541 SEV-SNP guests.
6549 to set it to "all" by meaning -- no limit here.
6630 using the csdlock_debug- kernel parameter.
6635 system. By default, let CSD-lock acquisition
6637 for this value provides a 5-minute timeout.
6639 smsc-ircc2.nopnp [HW] Don't use PNP to discover SMC devices
6640 smsc-ircc2.ircc_cfg= [HW] Device configuration I/O port
6641 smsc-ircc2.ircc_sir= [HW] SIR base I/O port
6642 smsc-ircc2.ircc_fir= [HW] FIR base I/O port
6643 smsc-ircc2.ircc_irq= [HW] IRQ line
6644 smsc-ircc2.ircc_dma= [HW] DMA channel
6645 smsc-ircc2.ircc_transceiver= [HW] Transceiver type:
6655 Default: -1 (no limit)
6658 [KNL] Should the soft-lockup detector generate panics.
6661 A value of 1 instructs the soft-lockup detector
6662 to panic the machine when a soft-lockup occurs. It is
6665 respective build-time switch to that functionality.
6668 [KNL] Should the soft-lockup detector generate
6673 See Documentation/admin-guide/laptops/sonypi.rst
6680 on - (default) Enable the HW or SW mitigation as
6683 vmexit - On systems which don't have the HW mitigation
6686 protected from VM-originated BHI attacks, but
6688 off - Disable the mitigation.
6695 on - unconditionally enable, implies
6697 off - unconditionally disable, implies
6699 auto - kernel detects whether your CPU model is
6718 retpoline - replace indirect branches
6719 retpoline,generic - Retpolines
6720 retpoline,lfence - LFENCE; indirect branch
6721 retpoline,amd - alias for retpoline,lfence
6722 eibrs - Enhanced/Auto IBRS
6723 eibrs,retpoline - Enhanced/Auto IBRS + Retpolines
6724 eibrs,lfence - Enhanced/Auto IBRS + LFENCE
6725 ibrs - use IBRS to protect kernel
6735 on - Unconditionally enable mitigations. Is
6738 off - Unconditionally disable mitigations. Is
6741 prctl - Indirect branch speculation is enabled,
6747 - Like "prctl" above, but only STIBP is
6753 - Same as "prctl" above, but all seccomp
6758 - Like "seccomp" above, but only STIBP is
6763 auto - Kernel selects the mitigation depending on
6774 off - Disable mitigation
6775 microcode - Enable microcode mitigation only
6776 safe-ret - Enable sw-only safe RET mitigation (default)
6777 ibpb - Enable mitigation by issuing IBPB on
6779 ibpb-vmexit - Issue IBPB only on VMEXIT
6780 (cloud-specific mitigation)
6805 on - Unconditionally disable Speculative Store Bypass
6806 off - Unconditionally enable Speculative Store Bypass
6807 auto - Kernel detects whether the CPU model contains an
6813 prctl - Control Speculative Store Bypass per thread
6817 seccomp - Same as "prctl" above, but all seccomp threads
6825 on,auto - On Power8 and Power9 insert a store-forwarding
6829 off - No action.
6843 off - not enabled
6845 warn - the kernel will emit rate-limited warnings
6853 fatal - the kernel will send SIGBUS to applications
6858 ratelimit:N -
6878 Certain CPUs are vulnerable to an MDS-like
6898 This kernel-boot parameter defaults to 128,
6899 but takes effect only when the low-order four
6916 instead of the compile-time CONFIG_NR_CPUS.
6920 grace-period sequence counter wrap for the
6921 srcu_data structure's ->srcu_gp_seq_needed field.
6936 Specifies the number of no-delay instances
6943 Specifies the per-grace-period phase, number of
6944 non-sleeping polls of readers. Beyond this limit,
6950 Specifies number of microseconds of non-sleeping
6951 delay between each non-sleeping poll of readers.
6954 Specifies the number of update-side contention
6959 set for contention-based conversions to occur.
6969 force-on: Unconditionally enable mitigation for
6971 force-off: Unconditionally disable mitigation for
6994 stacktrace_filter=[function-list]
6996 will trace at boot up. function-list is a comma-separated
7004 Set the STI (builtin display/keyboard on the HP-PARISC
7006 as the initial boot-console.
7066 to global on non-NUMA machines)
7091 <int> -- Number of I/O TLB slabs
7092 <int> -- Second integer after comma. Number of swiotlb
7095 force -- force using of bounce buffers even if they
7097 noforce -- Never use bounce buffers (for debugging)
7112 Ignore sysrq setting - this boot parameter will
7120 cache size. See Documentation/networking/ip-sysctl.rst
7127 Specify "mem" (for Suspend-to-RAM) or "standby" (for
7132 wakeup-capable RTC alarm.
7138 -1: disable all active trip points in all thermal zones
7142 -1: disable all critical trip points in all thermal zones
7149 -1: disable all passive trip points
7155 <deci-seconds>: poll all this frequency
7159 Format: <size>[KMG],<size>[KMG]:<state>;<size>[KMG]-<size>[KMG]:<state>
7164 See Documentation/admin-guide/mm/transhuge.rst for more
7172 Format: <size>[KMG],<size>[KMG]:<policy>;<size>[KMG]-<size>[KMG]:<policy>
7178 See Documentation/admin-guide/mm/transhuge.rst for more
7190 Prevent the CPU-hotplug component of torturing
7194 Dump the ftrace buffer at torture-test shutdown,
7198 with rotating-rust storage.
7203 disables verbose-printk() sleeping.
7206 Duration of each verbose-printk() sleep in jiffies.
7231 https://trustedcomputinggroup.org/resource/pc-client-platform-tpm-profile-ptp-specification/
7269 local - Use the per CPU time stamp counter
7273 global - Event time stamps are synchronize across
7276 counter - Simple counting of events (1, 2, ..)
7280 uptime - Use jiffies as the time stamp.
7281 perf - Use the same clock that perf uses.
7282 mono - Use ktime_get_mono_fast_ns() for time stamps.
7283 mono_raw - Use ktime_get_raw_fast_ns() for time
7285 boot - Use ktime_get_boot_fast_ns() for time stamps.
7289 trace_event=[event-list]
7291 to facilitate early boot debugging. The event-list is a
7292 comma-separated list of trace events to enable. See
7303 trace_instance=[instance-info]
7328 traceoff - Have the tracing instance tracing disabled after it is created.
7329 traceprintk - Have trace_printk() write into this trace instance
7376 trace_options=[option-list]
7378 The option-list is a comma delimited list of options
7392 trace_trigger=[trigger-list]
7438 See Documentation/admin-guide/mm/transhuge.rst
7445 See Documentation/admin-guide/mm/transhuge.rst
7452 See Documentation/admin-guide/mm/transhuge.rst
7460 - "tpm"
7461 - "tee"
7462 - "caam"
7463 - "dcp"
7473 - "kernel"
7474 - the same value as trusted.source: "tpm" or "tee"
7475 - "default"
7498 off - disable the mitigation
7499 on - enable the mitigation (default)
7500 user - mitigate only user/kernel transitions
7501 vm - mitigate only guest/host transitions
7509 high-resolution timer mode on older hardware, and in
7545 on - Enable TSX on the system. Although there are
7548 several previous speculation-related CVEs, and
7552 off - Disable TSX on the system. (Note that this
7560 auto - Disable TSX if X86_BUG_TAA is present,
7565 See Documentation/admin-guide/hw-vuln/tsx_async_abort.rst
7571 Similar to Micro-architectural Data Sampling (MDS)
7586 full - Enable TAA mitigation on vulnerable CPUs
7589 full,nosmt - Enable TAA mitigation and disable SMT on
7592 vulnerable to cross-thread TAA attacks.
7593 off - Unconditionally disable TAA mitigation
7595 On MDS-affected machines, tsx_async_abort=off can be
7607 Documentation/admin-guide/hw-vuln/tsx_async_abort.rst
7613 See also Documentation/input/devices/joystick-parport.rst
7615 udbg-immortal [PPC] When debugging early kernel crashes that
7621 Set number of hash buckets for UDP/UDP-Lite connections
7623 uhci-hcd.ignore_oc=
7625 Some badly-designed motherboards generate lots of
7650 unwind_debug [X86-64,EARLY]
7658 (default -1 = authorized (same as 1),
7664 for newly-detected USB devices (default 2). This
7692 [USB] Specifies timeout for the initial 64-byte
7699 [USB] A list of quirk entries to augment the built-in
7702 VendorID:ProductID:Flags. The IDs are 4-digit hex
7704 will change the built-in quirk; setting it if it is
7709 a 255-byte read);
7713 Set-Interface requests);
7732 (bInterval-1).
7770 usb-storage.delay_use=
7777 usb-storage.quirks=
7779 override the built-in unusual_devs list. List
7782 and Product ID values (4-digit hex numbers) and
7784 to a common usb-storage quirk flag as follows:
7826 medium is write-protected).
7835 1 - undefined instruction events
7836 2 - system calls
7837 4 - invalid data aborts
7838 8 - SIGSEGV faults
7839 16 - SIGBUS faults
7848 vdso32= [X86] Control the 32-bit vDSO
7849 vdso32=1: enable 32-bit VDSO
7850 vdso32=0 or vdso32=2: disable 32-bit VDSO
7860 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
7891 vga= [BOOT,X86-32] Select a particular video mode
7893 Documentation/admin-guide/svga.rst.
7908 - Disable all of the above options
7932 vsyscall= [X86-64,EARLY]
7935 code). Most statically-linked binaries and older
7959 see vga-softcursor.rst. Default: 2 = underline.
7964 This is a 16-member array composed of values
7965 ranging from 0-255.
7970 This is a 16-member array composed of values
7971 ranging from 0-255.
7976 This is a 16-member array composed of values
7977 ranging from 0-255.
7982 Set system-wide default UTF-8 mode for all tty's.
7983 Default is 1, i.e. UTF-8 mode is enabled for all
7988 Format=<-1|0|1>
7989 Set system-wide default for whether a cursor
7990 is shown on new VTs. Default is -1,
7995 vt.italic= [VT] Default color for italic text; 0-15.
7998 vt.underline= [VT] Default color for underlined text; 0-15.
8002 see Documentation/watchdog/watchdog-parameters.rst
8003 or other driver-specific files in the
8017 Format: <cpu-list>
8038 Per-cpu work items which run for longer than this
8041 them from noticeably delaying other per-cpu work
8059 Per-cpu workqueues are generally preferred because
8061 locality; unfortunately, per-cpu workqueues tend to
8064 Enabling this makes the per-cpu workqueues which
8078 Documentation/core-api/workqueue.rst.
8091 forces round-robin CPU selection to flush out
8099 on - Enable writecombine, use WUC for ioremap_wc()
8100 off - Disable writecombine, use SUC for ioremap_wc()
8102 x2apic_phys [X86-64,APIC,EARLY] Use x2apic physical mode instead of
8106 xen_512gb_limit [KNL,X86-64,XEN]
8116 ide-disks -- unplug primary master IDE devices
8117 aux-ide-disks -- unplug non-primary-master IDE devices
8118 nics -- unplug network devices
8119 all -- unplug all emulated devices (NICs and IDE disks)
8120 unnecessary -- unplugging emulated devices is
8123 never -- do not unplug even if version check succeeds
8137 Select whether to always use non-faulting (safe) MSR
8157 xen_timer_slop= [X86-64,XEN,EARLY]
8182 preferred over the 2-level event handling, as it is
8199 xive.store-eoi=off [PPC]
8205 xhci-hcd.quirks [USB,KNL]