Lines Matching +full:cross +full:- +full:arm64 +full:- +full:system
1 acpi= [HW,ACPI,X86,ARM64,RISCV64]
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
13 For ARM64 and RISCV64, ONLY "acpi=off", "acpi=on" or
26 If set to vendor, prefer vendor-specific driver
58 Documentation/firmware-guide/acpi/debug.rst for more information about
69 Some values produce so much output that the system is
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
220 acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
225 For broken nForce2 BIOS resulting in XT-PIC timer.
234 as soon as the kernel's real-mode entry point is called.
255 behave incorrectly in some ways with respect to system
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
299 allow_mismatched_32bit_el0 [ARM64]
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
304 EL0 is indicated by /sys/devices/system/cpu/aarch32_el0
305 and hot-unplug operations may be restricted.
307 See Documentation/arch/arm64/asymmetric-32bit.rst for more
310 amd_iommu= [HW,X86-64]
311 Pass parameters to the AMD IOMMU driver in the system.
313 fullflush - Deprecated, equivalent to iommu.strict=1
314 off - do not initialize any AMD IOMMU found in
315 the system
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
381 APC and your system crashes randomly.
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
418 arm64.nobti [ARM64] Unconditionally disable Branch Target
421 arm64.nomops [ARM64] Unconditionally disable Memory Copy and Memory
424 arm64.nomte [ARM64] Unconditionally disable Memory Tagging Extension
427 arm64.nopauth [ARM64] Unconditionally disable Pointer Authentication
430 arm64.nosme [ARM64] Unconditionally disable Scalable Matrix
433 arm64.nosve [ARM64] Unconditionally disable Scalable Vector
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.
545 the system trusted keyring to be used for certificate
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
660 [ARM,ARM64]
663 architected timer so that code using WFE-based polling
677 clocksource-wdtest.holdoff= [KNL]
683 cma=nn[MG]@[start[MG][-end[MG]]]
694 Sets the size of kernel per-numa memory area for
696 per-numa CMA altogether. And If this option is not
698 With per-numa CMA enabled, DMA users on node nid will
725 com20020= [HW,NET] ARCnet - COM20020 chipset
729 com90io= [HW,NET] ARCnet - COM90xx chipset (IO-mapped buffers)
733 ARCnet - COM90xx chipset (memory-mapped buffers)
762 See Documentation/admin-guide/serial-console.rst for more
772 Start an early, polled-mode console on the 8250/16550
775 MMIO inter-register address stride is either 8-bit
776 (mmio), 16-bit (mmio16), or 32-bit (mmio32).
780 the h/w is not re-initialized.
807 syscall, or to executing "dmesg -S --raw" or to reading
820 [ARM,ARM64]
831 disable the cpuidle sub-system
837 disable the cpufreq sub-system
845 [X86] Delay for N microsec between assert and de-assert
857 Run kdump after running panic-notifiers and dumping
870 [KNL, X86-64, ARM64, RISCV] Select a region under 4G first, and
873 See Documentation/admin-guide/kdump/kdump.rst for further details.
877 in the running system. The syntax of range is
878 start-[end] where start and end are both
880 Documentation/admin-guide/kdump/kdump.rst for an example.
883 [KNL, X86-64, ARM64, RISCV] range could be above 4G.
885 so could be above 4G if system have more than 4G ram
890 [KNL, X86-64, ARM64, RISCV] range under 4G. When crashkernel=X,high
892 above 4G, that cause second kernel crash on system
895 low memory is needed to make sure DMA buffers for 32-bit
899 --> x86: max(swiotlb_size_or_default() + 8MiB, 256MiB)
900 --> arm64: 128MiB
901 --> riscv: 128MiB
909 [KNL] Disable crypto self-tests
917 csdlock_debug= [KNL] Enable or disable debug add-ons of cross-CPU
932 See also Documentation/input/devices/joystick-parport.rst
945 [KNL] verbose locking self-tests
948 self-tests.
950 (no extra messages), setting it to -1 (all bits set)
951 will print _a_lot_ more information - normally only
962 amount of memory for normal system use. The maximum
978 disabled and the system will work mostly the same as a
986 Format: { on, no-mount, off }
988 no-mount:
993 get a -EPERM as result when trying to register files
997 Default value is set in build-time with a kernel configuration.
1009 Documentation/admin-guide/mm/hugetlbpage.rst.
1023 delayacct [KNL] Enable per-task delay accounting
1086 causing system reset or hang due to sending
1118 entries for DMA-API debugging code. One entry is
1119 required per DMA-API allocation. Use this if the
1120 DMA-API debugging code disables itself because the
1124 With this option the DMA-API debugging driver
1148 Documentation/admin-guide/hw-vuln/reg-file-data-sampling.rst
1162 Generic built-in EDID data sets are used, if one of
1167 available in Documentation/admin-guide/edid.rst. An EDID
1179 Control how the dt_cpu_ftrs device-tree binding is
1189 what data is available or for reverse-engineering.
1194 Documentation/admin-guide/dynamic-debug-howto.rst
1205 determined by stdout-path property in device tree's
1210 Start an early, polled-mode console on a Cadence
1221 Start an early, polled-mode console on the 8250/16550
1223 MMIO inter-register address stride is either 8-bit
1224 (mmio) or 32-bit (mmio32 or mmio32be).
1234 Start an early, polled-mode console on a pl011 serial
1238 the driver will use only 32-bit accessors to read/write
1247 Start an early, polled-mode console on a meson serial
1253 Start an early, polled-mode console on an msm serial
1259 Start an early, polled-mode console on an msm serial
1265 Start an early, polled-mode console on a serial port
1271 Start an early, polled-mode console on a serial port
1277 Use RISC-V SBI (Supervisor Binary Interface) for early
1295 Start an early, polled-mode console on a lantiq serial
1309 Start an early, polled-mode, output-only console on the
1314 Start an early, polled-mode console on the
1320 Start an early, polled-mode console on a Qualcomm
1328 coherent non-x86 systems that use system memory for
1409 (i.e. EFI_CONVENTIONAL_MEMORY / "System RAM").
1428 attribute is added to range 0x100000000-0x180000000 and
1429 0x10a0000000-0x1120000000.
1433 range 0x240000000-0x43fffffff.
1445 Documentation/admin-guide/acpi/ssdt-overlays.rst for details.
1462 elanfreq= [X86-32]
1470 See Documentation/admin-guide/kdump/kdump.rst for details.
1486 0 -- permissive (log only, no denials).
1487 1 -- enforcing (deny and log).
1519 See also Documentation/fault-injection/.
1523 See Documentation/admin-guide/sysctl/net.rst for
1527 See Documentation/admin-guide/blockdev/floppy.rst.
1530 [IA-64] Avoid check_sal_cache_flush which may hang on
1535 forcepae [X86-32]
1571 ftrace_filter=[function-list]
1573 tracer at boot up. function-list is a comma-separated
1578 ftrace_notrace=[function-list]
1580 function-list. This list can be changed at run time
1584 ftrace_graph_filter=[function-list]
1587 function-list is a comma-separated list of functions
1591 ftrace_graph_notrace=[function-list]
1593 function-list. This list is a comma-separated list of
1613 off -- Don't create device links from firmware info.
1614 permissive -- Create device links from firmware info
1617 on -- Create device links from firmware info and use it
1619 rpm -- Like "on", but also use to order runtime PM.
1632 strict -- Default. Continue waiting on consumers to
1634 timeout -- Give up waiting on consumers and call
1644 See also Documentation/input/devices/joystick-parport.rst
1648 gart_fix_e820= [X86-64] disable the fix e820 for K8 GART
1672 gcov_persist= [GCOV] When non-zero (default), profiling data for
1682 gpio-mockup.gpio_mockup_ranges
1685 gpio-mockup.gpio_mockup_named_lines
1717 against bounds-checking flaws in the kernel's
1723 [KNL] Should the hard-lockup detector generate
1729 for 64-bit NUMA, off otherwise.
1732 hcl= [IA-64] SGI's Hardware Graph compatibility layer
1739 corresponding firmware-first mode error processing
1749 during restoration read-only).
1764 This allows setting the system's hostname during early
1775 hpet= [X86-32,HPET] option to control HPET usage
1792 number of pages to allocate per-node can be specified.
1793 See also Documentation/admin-guide/mm/hugetlbpage.rst.
1804 Documentation/admin-guide/mm/hugetlbpage.rst.
1815 boot-time allocation of gigantic hugepages is skipped.
1843 by the CONFIG_BOOTPARAM_HUNG_TASK_PANIC build-time
1849 hvc_iucv_allow= [S390] Comma-separated list of z/VM user IDs.
1866 (disabled by default, and as a pre-condition
1868 i8042.direct [HW] Put keyboard port into non-translated mode
1882 suspend-to-ram transitions, only during s2r
1906 -1 -- never invert brightness
1907 0 -- machine default
1908 1 -- force brightness inversion
1918 will use a lot of power and make the system run hot.
1922 idle=nomwait: Disable mwait for CPU C-states
1950 legacy only accept legacy-NaN binaries, if supported
1952 2008 only accept 2008-NaN binaries, if supported
1961 'relaxed' straps the emulator for both legacy-NaN and
1962 2008-NaN, whereas 'strict' enables legacy-NaN only on
1971 Ignore loglevel setting - this will print /all/
2038 Formats: { "ima" | "ima-ng" | "ima-ngv2" | "ima-sig" |
2039 "ima-sigv2" }
2040 Default: "ima-ng"
2072 initcall_blacklist= [KNL] Do not execute a comma-separated list of
2073 initcall functions. Useful for debugging built-in
2118 0 -- basic integrity auditing messages. (Default)
2119 1 -- additional integrity auditing messages.
2147 could harm performance of some high-throughput
2151 provided by tboot because it makes the system
2156 1 to 9 specify maximum depth of C-state.
2165 algorithms for p-state selection. There are two
2166 P-state selection algorithms provided by
2169 on whether or not the hardware managed P-states
2176 used along with the hardware-managed P-states (HWP)
2180 in favor of acpi-cpufreq. Forcing the intel_pstate driver
2181 instead of acpi-cpufreq may disable platform features, such
2183 P-States information being indicated to OSPM and therefore
2186 or on platforms that use pcc-cpufreq instead of acpi-cpufreq.
2199 Allow per-logical-CPU P-State performance control limits using
2202 intremap= [X86-64, Intel-IOMMU]
2207 BIOS x2APIC opt-out request will be ignored
2229 iommu.forcedac= [ARM64, X86] Control IOVA allocation for PCI devices.
2231 0 - Try to allocate a 32-bit DMA address first, before
2233 1 - Allocate directly from the full usable range,
2235 greater than 32-bit addressing.
2237 iommu.strict= [ARM64, X86] Configure TLB invalidation behaviour
2239 0 - Lazy mode.
2245 1 - Strict mode.
2248 unset - Use value of CONFIG_IOMMU_DEFAULT_DMA_{LAZY,STRICT}.
2250 legacy driver-specific options takes precedence.
2253 [ARM64, X86] Configure DMA to bypass the IOMMU by default.
2255 0 - Use IOMMU translation for DMA.
2256 1 - Bypass the IOMMU for DMA.
2257 unset - Use value of CONFIG_IOMMU_DEFAULT_PASSTHROUGH.
2259 io7= [HW] IO7 for Marvel-based Alpha systems
2274 See Documentation/admin-guide/nfs/nfsroot.rst.
2276 ipcmni_extend [KNL] Extend the maximum number of unique System V
2283 [ARM, ARM64]
2290 [ARM, ARM64]
2292 LPIs (and by consequence ITSs). Intended for system
2297 irqchip.gicv3_pseudo_nmi= [ARM64]
2298 Enables support for pseudo-NMIs in the kernel. This
2317 [Deprecated - use cpusets instead]
2318 Format: [flag-list,]<cpu-list>
2349 "number of CPUs in system - 1".
2375 The format of <cpu-list> is described above.
2379 ivrs_ioapic [HW,X86-64]
2380 Provide an override to the IOAPIC-ID<->DEVICE-ID
2384 For example, to map IOAPIC-ID decimal 10 to
2390 * To map IOAPIC-ID decimal 10 to PCI device 00:14.0
2393 * To map IOAPIC-ID decimal 10 to PCI segment 0x1 and
2397 ivrs_hpet [HW,X86-64]
2398 Provide an override to the HPET-ID<->DEVICE-ID
2402 For example, to map HPET-ID decimal 10 to
2408 * To map HPET-ID decimal 0 to PCI device 00:14.0
2411 * To map HPET-ID decimal 10 to PCI segment 0x1 and
2415 ivrs_acpihid [HW,X86-64]
2416 Provide an override to the ACPI-HID:UID<->DEVICE-ID
2420 For example, to map UART-HID:UID AMD0020:0 to
2426 * To map UART-HID:UID AMD0020:0 to PCI segment is 0,
2429 * To map UART-HID:UID AMD0020:0 to PCI segment 0x1 and
2450 kernelcore= [KNL,X86,IA-64,PPC]
2453 the kernel for non-movable allocations. The requested
2455 system as ZONE_NORMAL. The remaining memory is used for
2463 subsystem. Note that allocations like PTEs-from-HighMem
2468 the form of "nn[KMGTPE]", a percentage of total system
2471 for non-movable allocations and remaining memory is used
2482 gdb or control-c on the dbgp connection. When
2483 not using this parameter you use sysrq-g to break into
2488 or a supported polling keyboard driver (non-usb).
2515 Configure the RouterBoard 532 series on-chip
2518 kmemleak= [KNL] Boot-time kmemleak enable/disable
2524 kprobe_event=[probe-list]
2526 The probe-list is a semicolon delimited list of probe
2537 kpti= [ARM64] Control page table isolation of user
2556 execution by eliminating the write-protection faults
2601 back to huge pages. If the value is a non-zero N, KVM will
2606 kvm-amd.nested= [KVM,AMD] Control nested virtualization feature in
2609 kvm-amd.npt= [KVM,AMD] Control KVM's use of Nested Page Tables,
2610 a.k.a. Two-Dimensional Page Tables. Default is 1
2614 kvm-arm.mode=
2615 [KVM,ARM] Select one of KVM/arm64's modes of operation.
2619 nvhe: Standard nVHE-based mode, without support for
2622 protected: nVHE-based mode with support for guests whose
2625 nested: VHE-based mode with support for nested
2634 kvm-arm.vgic_v3_group0_trap=
2635 [KVM,ARM] Trap guest accesses to GICv3 group-0
2636 system registers
2638 kvm-arm.vgic_v3_group1_trap=
2639 [KVM,ARM] Trap guest accesses to GICv3 group-1
2640 system registers
2642 kvm-arm.vgic_v3_common_trap=
2644 system registers
2646 kvm-arm.vgic_v4_enable=
2651 Reserves given percentage from system memory area for
2654 By default it reserves 5% of total system memory.
2658 kvm-intel.ept= [KVM,Intel] Control KVM's use of Extended Page Tables,
2659 a.k.a. Two-Dimensional Page Tables. Default is 1
2663 kvm-intel.emulate_invalid_guest_state=
2665 state. Ignored if kvm-intel.enable_unrestricted_guest=1,
2671 kvm-intel.flexpriority=
2676 kvm-intel.nested=
2680 kvm-intel.unrestricted_guest=
2686 kvm-intel.vmentry_l1d_flush=[KVM,Intel] Mitigation for L1 Terminal Fault
2687 CVE-2018-3620.
2698 kvm-intel.vpid= [KVM,Intel] Control KVM's use of Virtual Processor
2718 on - enable the interface for the mitigation
2783 For details see: Documentation/admin-guide/hw-vuln/l1tf.rst
2789 lapic [X86-32,APIC] Enable the local APIC even if BIOS
2793 value for LAPIC timer one-shot implementation. Default
2816 libata.force= [LIBATA] Force configurations. The format is a comma-
2828 first fan-out link behind PMP device. It does not
2842 * Transfer mode: pio[0-7], mwdma[0-4] and udma[0-7].
2849 * rstonce: only attempt one reset during hot-unplug
2931 Set the number of locking read-acquisition kthreads.
2936 Set the number of locking write-acquisition kthreads.
2939 Set time (s) after boot for CPU-hotplug testing.
2942 Set time (s) between CPU-hotplug operations, or
2943 zero to disable CPU-hotplug testing.
2946 Set task-shuffle interval (jiffies). Shuffling
2947 tasks allows some CPUs to go into dyntick-idle
2951 Set time (s) after boot system shutdown. This
2952 is useful for hands-off automated testing.
2968 Run the write-side locktorture kthreads at
2969 sched_set_fifo() real-time priority.
2982 0 (KERN_EMERG) system is unusable
2989 7 (KERN_DEBUG) debug-level messages
2999 logo.nologo [FB] Disables display of the built-in Linux logo.
3017 an IEEE 1284-compliant printer is attached; if
3023 time-consuming boot-time autodetection (up to 250 ms per
3044 machvec= [IA-64] Force the use of a particular machine-vector
3050 Example: machtype=lemote-yeeloong-2f-7inch
3052 max_addr=nn[KMG] [KNL,BOOT,IA-64] All physical memory greater
3059 "echo 1 > /sys/devices/system/cpu/cpuX/online". So maxcpus
3060 only takes effect during system bootup.
3065 (loop.max_loop) unconditionally pre-created at init time. The default
3068 devices can be requested on-demand with the
3069 /dev/loop-control interface.
3071 mce [X86-32] Machine Check Exception
3073 mce=option [X86-64] See Documentation/arch/x86/x86_64/boot-options.rst
3076 See Documentation/admin-guide/md.rst.
3083 Control mitigation for the Micro-architectural Data
3098 full - Enable MDS mitigation on vulnerable CPUs
3099 full,nosmt - Enable MDS mitigation and disable
3101 off - Unconditionally disable MDS mitigation
3103 On TAA-affected machines, mds=off can be prevented by
3112 For details see: Documentation/admin-guide/hw-vuln/mds.rst
3121 2 when the kernel is not able to see the whole system memory;
3126 [ARC,MICROBLAZE] - the limit applies only to low memory,
3129 [ARM64] - only limits memory covered by the linear
3139 if system memory of hypervisor is not sufficient.
3142 [ARM,MIPS] - override the memory layout reported by
3149 mem=nopentium [BUGS=X86-32] Disable usage of 4MB pages for kernel
3156 per-device physically contiguous DMA buffers.
3164 See Documentation/admin-guide/mm/memory-hotplug.rst.
3189 Example: Exclude memory from 0x18690000-0x1869ffff
3203 memmap=<size>%<offset>-<oldtype>+<newtype>
3205 from <oldtype> to <newtype>. If "-<oldtype>" is left
3220 repeatable BIOS-originated corruption always
3264 mem_encrypt= [X86-64] AMD Secure Memory Encryption (SME) control
3270 Refer to Documentation/virt/kvm/x86/amd-memory-encryption.rst
3273 mem_sleep_default= [SUSPEND] Default system suspend mode:
3274 s2idle - Suspend-To-Idle
3275 shallow - Power-On Suspend or equivalent (if supported)
3276 deep - Suspend-To-RAM or equivalent (if supported)
3277 See Documentation/admin-guide/pm/sleep-states.rst.
3282 mfgpt_irq= [IA-32] Specify the IRQ to use for the
3283 Multi-Function General Purpose Timers on AMD Geode
3286 mfgptfix [X86-32] Fix MFGPT timers on AMD Geode platforms when
3298 min_addr=nn[KMG] [KNL,BOOT,IA-64] All physical memory below this
3305 0 - The attached screen is the 3.5" TFT
3306 1 - The attached screen is the 7" TFT
3307 2 - The VGA Shield is attached (1024x768)
3311 b - Enable backlight. The TFT backlight pin will be
3315 c - Enable the s3c camera interface.
3316 t - Reserved for enabling touchscreen support. The
3320 https://repo.or.cz/w/linux-2.6/mini2440.git
3323 [X86,PPC,S390,ARM64] Control optional mitigations for
3325 arch-independent options, each of which is an
3326 aggregation of existing arch-specific options.
3333 improves system performance, but it may also
3335 Equivalent to: if nokaslr then kpti=0 [ARM64]
3345 nospectre_bhb [ARM64]
3347 nospectre_v2 [X86,PPC,S390,ARM64]
3354 ssbd=force-off [ARM64]
3367 have other ways of avoiding SMT-based attacks.
3402 full - Enable mitigation on vulnerable CPUs
3404 full,nosmt - Enable mitigation and disable SMT on
3407 off - Unconditionally disable mitigation
3420 Documentation/admin-guide/hw-vuln/processor_mmio_stale_data.rst
3450 module_blacklist= [KNL] Do not load a comma-separated list of
3464 movablecore= [KNL,X86,IA-64,PPC]
3475 movable_node [KNL] Boot-time switch to make hotplugable memory
3482 Format: <name>,<region-number>,<size>,<offset>
3485 <name>,<region-number>[,<base>,<size>,<buswidth>,<altbuswidth>]
3493 See arch/arm/mach-s3c/mach-jive.c
3529 something different and driver-specific.
3562 [NFS] enable 64-bit inode numbers.
3563 If zero, the NFS client will fake up a 32-bit inode
3565 of returning the full 64-bit number.
3566 The default is to return 64-bit inode numbers.
3601 [NFS4] Specify an additional fixed unique ident-
3604 UUID that is generated at system install time.
3632 driver. A non-zero value sets the minimum interval
3637 server-to-server copies for which this server is
3649 server-to-server copy, knfsd temporarily mounts
3656 See Documentation/admin-guide/nfs/nfsroot.rst.
3658 nfsroot= [NFS] nfs root filesystem for disk-less boxes.
3659 See Documentation/admin-guide/nfs/nfsroot.rst.
3662 See Documentation/admin-guide/nfs/nfsroot.rst.
3666 NMI stack-backtrace request.
3675 0 - turn hardlockup detector in nmi_watchdog off
3676 1 - turn hardlockup detector in nmi_watchdog on
3688 no387 [BUGS=X86-32] Tells the kernel to use the 387 maths
3692 no4lvl [RISCV] Disable 4-level and 5-level paging modes. Forces
3693 kernel to use 3-level paging instead.
3695 no5lvl [X86-64,RISCV] Disable 5-level paging mode. Forces
3696 kernel to use 4-level paging instead.
3699 caches in the slab allocator. Saves per-node memory,
3708 IOAPICs that may be present in the system.
3719 of the system is being put to sleep (ie, while
3736 no_entry_flush [PPC] Don't flush the L1-D cache when entering the kernel.
3738 noexec [IA-64]
3740 noexec32 [X86-64]
3741 This affects only 32-bit executables.
3742 noexec32=on: enable non-executable mappings (default)
3744 noexec32=off: disable non-executable mappings
3755 nofxsr [BUGS=X86-32] Disables x86 floating point extended
3757 legacy floating-point registers on task switch.
3759 nohalt [IA-64] Tells the kernel not to use the power saving
3761 power-consumption. On the positive side, it reduces
3762 interrupt wake-up latency, which may improve performance
3764 real-time systems.
3774 compared. However, if this command-line option is
3782 nohlt [ARM,ARM64,MICROBLAZE,MIPS,PPC,SH] Forces the kernel to
3786 sleep(SH) or wfi(ARM,ARM64) instructions do not work
3791 nohugeiomap [KNL,X86,PPC,ARM64] Disable kernel huge I/O mappings.
3793 nohugevmalloc [KNL,X86,PPC,ARM64] Disable kernel huge vmalloc mappings.
3815 nointremap [X86-64, Intel-IOMMU] Do not enable interrupt
3817 [Deprecated - use intremap=off]
3819 nointroute [IA-64]
3825 noirqdebug [X86-32] Disables the code which attempts to detect and
3830 nojitter [IA-64] Disables jitter checking for ITC timers.
3837 no-kvmapf [X86,KVM] Disable paravirtualized asynchronous page
3840 no-kvmclock [X86,KVM] Disable paravirtualized KVM clock driver
3842 nolapic [X86-32,APIC] Do not enable or use the local APIC.
3844 nolapic_timer [X86-32,APIC] Do not use the local APIC timer.
3846 nomca [IA-64] Disable machine check abort handling
3848 nomce [X86-32] Disable Machine Check Exception
3850 nomfgpt [X86-32] Disable Multi-Function General Purpose
3856 not load if they could possibly displace the pre-
3857 initialized output. Only the system framebuffer will
3859 perform display-mode changes or accelerated rendering.
3872 nopcid [X86-64] Disable the PCID cpu feature.
3877 nopti [X86-64]
3893 noreplace-smp [X86-32,SMP] Don't replace SMP instructions
3899 nosbagart [IA-64]
3901 no-scroll [VGA] Disables scrollback.
3902 This is required for the Braillex ib80-piezo Braille
3905 nosgx [X86-64,SGX] Disables Intel SGX kernel support.
3925 nosoftlockup [KNL] Disable the soft-lockup detector.
3930 nospectre_bhb [ARM64] Disable all mitigations for Spectre-BHB (branch
3931 history injection) vulnerability. System may allow data leaks
3936 possible in the system.
3938 nospectre_v2 [X86,PPC_E500,ARM64] Disable all mitigations for
3940 vulnerability. System may allow data leaks with this
3943 no-steal-acc [X86,PV_OPS,ARM64,PPC/PSERIES] Disable paravirtualized
3953 [PPC] Don't flush the L1-D cache after accessing user data.
3966 no-vmw-sched-clock
3971 soft-lockup and NMI watchdog (hard-lockup).
3975 nox2apic [X86-64,APIC] Do not enable x2APIC mode.
3983 enabling legacy floating-point and sse state.
4009 nptcg= [IA-64] Override max number of concurrent global TLB
4018 n. So during boot up some boot time memory for per-cpu
4019 variables need be pre-allocated for later physical cpu
4024 numa=off [KNL, ARM64, PPC, RISCV, SPARC, X86] Disable NUMA, Only
4027 numa_balancing= [KNL,ARM64,PPC,RISCV,S390,X86] Enable or disable automatic
4034 See Documentation/admin-guide/sysctl/vm.rst for details.
4037 See Documentation/core-api/debugging-via-ohci1394.rst for more
4052 onenand.bdry= [HW,MTD] Flex-OneNAND Boundary Configuration
4056 boundary - index of last SLC block on Flex-OneNAND.
4058 lock - Configure if Flex-OneNAND boundary should be locked.
4072 running on a platform with a direct-mapped memory-side
4078 page_owner= [KNL] Boot-time page_owner enabling option.
4084 page_poison= [KNL] Boot-time parameter changing the state of
4111 See Documentation/admin-guide/tainted-kernels.rst for
4118 panic_print= Bitmask for printing system info when panic happens.
4121 bit 1: print system memory info
4163 Set to non-zero to probe primary and secondary ISA
4169 Set to non-zero if a chip is present that snoops speed
4217 Set to non-zero to probe tertiary and further ISA
4233 Set to non-zero to probe QDI controllers. By default
4238 Set to non-zero to probe Winbond controllers. Use
4280 devices in the system.
4285 bios [X86-32] force use of PCI BIOS, don't access
4287 has a non-standard PCI host bridge.
4288 nobios [X86-32] disallow use of PCI BIOS, only direct
4294 data in IO port 0xCFC, both 32-bit).
4296 Mechanism 2 (IO port 0xCF8 is an 8-bit port for
4297 the function, IO port 0xCFA, also 8-bit, sets
4299 through ports 0xC000-0xCFFF).
4306 root domains (aka PCI segments, in ACPI-speak).
4314 disable the use of MSI interrupts system-wide.
4319 primary IO-APIC for bridges that cannot disable
4321 when the system masks IRQs.
4326 biosirq [X86-32] Use PCI BIOS calls to get the interrupt
4350 F0000h-100000h range.
4355 assign-busses [X86] Always assign all PCI bus
4376 <linux-pci@vger.kernel.org>.
4380 a bug to <linux-pci@vger.kernel.org>.
4392 bfsort Sort PCI devices into breadth-first order.
4395 nobfsort Don't sort PCI devices into breadth-first order.
4397 tuning and use the BIOS-configured MPS defaults.
4407 configuration allows peer-to-peer DMA between
4410 that hot-added devices will work.
4425 A PCI-PCI bridge can be specified if resource
4431 for 4096-byte alignment.
4433 end-to-end CRC checking). Only effective if
4464 noats [PCIE, Intel-IOMMU, AMD-IOMMU]
4493 WARNING: Forcing ASPM on may cause system lockups.
4500 dpc-native Use native PCIe service for DPC only. May
4517 Keep all power-domains already enabled by bootloader on,
4534 pirq= [SMP,APIC] Manual mp-table setup
4535 See Documentation/arch/x86/i386/IO-APIC.rst.
4539 See also Documentation/admin-guide/parport.rst.
4558 CONFIG_PNP_DEBUG_MESSAGES option). Change at run-time
4567 { on | off | curr | res | no-curr | no-res }
4607 none - Limited to cond_resched() calls
4608 voluntary - Limited to cond_resched() and might_sleep() calls
4609 full - Any section that isn't explicitly preempt disabled
4612 print-fatal-signals=
4618 coredump - etc.
4621 you might want to try "ulimit -i unlimited".
4633 or lockdep-detected issues (only if lock debug is on).
4642 on - unlimited logging to /dev/kmsg from userspace
4643 off - logging to /dev/kmsg disabled
4644 ratelimit - ratelimit the logging
4655 - 'always': traditional behavior always allows mem overrides.
4656 - 'ptrace': only allow mem overrides for active ptracers.
4657 - 'never': never allow mem overrides.
4661 Limit processor to maximum C-state
4665 Ignore the _CST method to determine C-states,
4672 Param: "schedule" - profile schedule points.
4673 Param: "kvm" - profile VM exits.
4674 Param: <number> - step/bucket size as a power of 2 for
4703 pti= [X86-64] Control Page Table Isolation of user and
4706 system calls and interrupts.
4708 on - unconditionally enable
4709 off - unconditionally disable
4710 auto - kernel detects whether your CPU model is
4716 [KNL] Number of legacy pty's. Overwrites compiled-in
4728 See Documentation/admin-guide/md.rst.
4731 See Documentation/admin-guide/blockdev/ramdisk.rst.
4750 cross-syscall address exposures. This is only
4756 ras=option[,option,...] [KNL] RAS-specific options
4762 rcu_nocbs[=cpu-list]
4767 enable the no-callback CPU mode, which prevents
4772 "p" for RCU-preempt, "s" for RCU-sched, and "g"
4776 and real-time workloads. It can also improve
4780 list of CPUs is set to no-callback mode from boot.
4784 no-callback mode from boot but the mode may be
4795 This improves the real-time response for the
4812 RCU grace-period cleanup.
4816 RCU grace-period initialization.
4820 RCU grace-period pre-initialization, that is,
4821 the propagation of recent CPU-hotplug changes up
4825 Set delay from grace-period initialization to
4838 soliciting quiescent-state help from
4850 Set the SCHED_FIFO priority of the RCU per-CPU
4853 and for the RCU grace-period kthreads (rcu_bh,
4855 set, valid values are 1-99 and the default is 1
4856 (the least-favored priority). Otherwise, when
4857 RCU_BOOST is not set, valid values are 0-99 and
4858 the default is zero (non-realtime operation).
4863 On callback-offloaded (rcu_nocbs) CPUs,
4866 use of the ->nocb_bypass list. However, in the
4867 common non-flooded case, RCU queues directly to
4868 the main ->cblist in order to avoid the extra
4869 overhead of the ->nocb_bypass list and its lock.
4871 a single jiffy, RCU pre-queues the callbacks into
4872 the ->nocb_bypass queue. The definition of "too
4881 batch limiting is re-enabled.
4885 RCU's force-quiescent-state scan will aggressively
4893 Set the page-cache refill delay (in milliseconds)
4894 in response to low-memory conditions. The range
4898 Set the shift-right count to use to compute
4899 the callback-invocation batch limit bl from
4906 Please note that this callback-invocation batch
4907 limit applies only to non-offloaded callback
4916 cache-to-cache transfer latencies.
4922 and for NUMA systems with large remote-access
4938 the wakeup overhead on the global grace-period
4940 each group's NOCB grace-period kthread.
4943 Cause the grace-period kthread to get an extra
4945 it should at force-quiescent-state time.
4958 this specifies an rcu_read_unlock()-time delay
4962 of RCU-protected pointers after the relevant
4972 per-CPU rcuc kthreads. Defaults to a non-zero
4982 grace-period primitives such as call_rcu().
4993 grace-period primitives.
4996 Set test-start holdoff period. The purpose of
5014 Test the double-argument variant of kfree_rcu().
5016 rcuscale.kfree_rcu_test_single, both the single-
5017 and double-argument variants are tested.
5020 Test the single-argument variant of kfree_rcu().
5022 rcuscale.kfree_rcu_test_double, both the single-
5023 and double-argument variants are tested.
5037 does not affect the data-collection interval,
5042 Set number of RCU readers. The value -1 selects
5044 "n" less than -1 selects N-n+1, where N is again
5045 the number of CPUs. For example, -2 selects N
5046 (the number of CPUs), -3 selects N+1, and so on.
5047 A value of "n" less than or equal to -N selects
5059 Shut the system down after performance tests
5060 complete. This is useful for hands-off automated
5067 Write-side holdoff between grace periods,
5072 Additional write-side holdoff between grace
5090 for RCU grace-period forward-progress testing
5097 Specify the fraction of a CPU-stall-warning
5098 period to do tight-loop forward-progress testing.
5102 forward-progress tests.
5106 need_resched() during tight-loop forward-progress
5110 Use conditional/asynchronous update-side
5114 Use expedited update-side primitives, if available.
5117 Use normal (non-expedited) asynchronous
5118 update-side primitives, if available.
5121 Use normal (non-expedited) synchronous
5122 update-side primitives, if available. If all
5126 they are all non-zero.
5134 Leak an RCU-protected pointer out of the reader.
5149 Set number of RCU callback-offload togglers.
5154 callback-offload toggling attempts.
5157 Set number of RCU readers. The value -1 selects
5158 N-1, where N is the number of CPUs. A value
5159 "n" less than -1 selects N-n-2, where N is again
5160 the number of CPUs. For example, -2 selects N
5161 (the number of CPUs), -3 selects N+1, and so on.
5164 Enable debug-object double-call_rcu() testing.
5167 Set time (s) after boot for CPU-hotplug testing.
5170 Set time (jiffies) between CPU-hotplug operations,
5171 or zero to disable CPU-hotplug testing.
5174 Set the number of read-then-exit kthreads used
5176 task-exit processing.
5179 The number of times in a given read-then-exit
5180 episode that a set of read-then-exit kthreads
5185 read-then-exit testing episodes.
5188 Set task-shuffle interval (s). Shuffling tasks
5189 allows some CPUs to go into dyntick-idle mode
5193 Set time (s) after boot system shutdown. This
5194 is useful for hands-off automated testing.
5203 any other stall-related activity. Note that
5209 in scheduling-while-atomic splats.
5222 grace-period kthread to test RCU CPU stall
5248 Test RCU's dyntick-idle handling. See also the
5297 Use expedited grace-period primitives, for
5301 real-time latency, and degrade energy efficiency.
5305 Use only normal grace-period primitives,
5308 real-time latency, CPU utilization, and
5310 increased grace-period latency. This parameter
5317 only normal grace-period primitives. No effect
5323 post-boot attempt at an expedited RCU grace
5324 period to instead use normal non-expedited
5325 grace-period processing.
5333 set to the default value of -1.
5336 Set the minimum number of callback-queuing-time
5337 lock-contention events per jiffy required to
5338 cause the RCU Tasks flavors to switch to per-CPU
5341 the default value of -1.
5346 of -1 allows this to be automatically (and
5354 number avoids disturbing real-time workloads,
5359 cancel laziness on that CPU. Use -1 to disable
5369 only printed prior to the stall-warning message
5425 force - Override the decision by the kernel to hide the
5453 Set test-start holdoff period. The purpose of
5462 but the default has already reduced the per-pass
5467 Set number of readers. The default value of -1
5476 Set the read-side critical-section duration,
5480 Specify the read-protection implementation to test.
5483 Shut down the system at the end of the performance
5499 See Documentation/admin-guide/cgroup-v1/cpusets.rst.
5507 reservetop= [X86-32]
5524 See Documentation/power/swsusp-and-swap-files.rst
5539 AMD-based UNRET and IBPB mitigations alone do not stop
5541 sibling threads. For that reason, STIBP is used on pro-
5545 off - no mitigation
5546 auto - automatically select a migitation
5547 auto,nosmt - automatically select a mitigation,
5551 ibpb - On AMD, mitigate short speculation
5556 ibpb,nosmt - Like "ibpb" above but will disable SMT
5560 unret - Force enable untrained return thunks,
5561 only effective on AMD f15h-f17h based
5563 unret,nosmt - Like unret, but will disable SMT when STIBP
5598 ro [KNL] Mount root device read-only on boot
5601 on Mark read-only kernel memory as read-only (default).
5602 off Leave read-only kernel memory writable for debugging.
5603 full Mark read-only kernel memory and aliases as read-only
5604 [arm64]
5609 debug-uart get routed to the D+ and D- pins of the usb
5615 block/early-lookup.c for details.
5618 system, or "mtd" and "ubi" for mounting from raw flash.
5640 rw [KNL] Mount root device read-write on boot
5692 to 10 seconds for built-in smp_call_function()
5699 that requesting even small non-zero numbers of
5706 The default of -1 specifies a number of kthreads
5711 test before initiating CPU-hotplug operations.
5715 CPU-hotplug operations. Specifying zero (which
5716 is the default) disables CPU-hotplug operations.
5720 test after which to shut down the system. The
5721 default of zero avoids shutting down the system.
5722 Non-zero values are useful for automated tests.
5745 "wait" parameter. A value of -1 selects the
5746 default if all other weights are -1. However,
5748 value of -1 will instead select a weight of zero.
5753 non-zero "wait" parameter. See weight_single.
5761 on the system.
5766 non-zero "wait" parameter. See weight_single
5778 non-zero "wait" parameter. See weight_single
5785 0 -- disable. (may be 1 via CONFIG_CMDLINE="skew_tick=1"
5786 1 -- enable.
5797 0 -- disable.
5798 1 -- enable.
5801 serialnumber [BUGS=X86-32]
5803 sev=option[,option...] [X86-64] See Documentation/arch/x86/x86_64/boot-options.rst
5811 to set it to "all" by meaning -- no limit here.
5817 simeth= [IA-64]
5892 using the csdlock_debug- kernel parameter.
5897 system. By default, let CSD-lock acquisition
5899 for this value provides a 5-minute timeout.
5901 smsc-ircc2.nopnp [HW] Don't use PNP to discover SMC devices
5902 smsc-ircc2.ircc_cfg= [HW] Device configuration I/O port
5903 smsc-ircc2.ircc_sir= [HW] SIR base I/O port
5904 smsc-ircc2.ircc_fir= [HW] FIR base I/O port
5905 smsc-ircc2.ircc_irq= [HW] IRQ line
5906 smsc-ircc2.ircc_dma= [HW] DMA channel
5907 smsc-ircc2.ircc_transceiver= [HW] Transceiver type:
5917 Default: -1 (no limit)
5920 [KNL] Should the soft-lockup detector generate panics.
5923 A value of 1 instructs the soft-lockup detector
5924 to panic the machine when a soft-lockup occurs. It is
5927 respective build-time switch to that functionality.
5930 [KNL] Should the soft-lockup detector generate
5935 See Documentation/admin-guide/laptops/sonypi.rst
5942 on - (default) Enable the HW or SW mitigation
5944 off - Disable the mitigation.
5951 on - unconditionally enable, implies
5953 off - unconditionally disable, implies
5955 auto - kernel detects whether your CPU model is
5972 retpoline - replace indirect branches
5973 retpoline,generic - Retpolines
5974 retpoline,lfence - LFENCE; indirect branch
5975 retpoline,amd - alias for retpoline,lfence
5976 eibrs - Enhanced/Auto IBRS
5977 eibrs,retpoline - Enhanced/Auto IBRS + Retpolines
5978 eibrs,lfence - Enhanced/Auto IBRS + LFENCE
5979 ibrs - use IBRS to protect kernel
5989 on - Unconditionally enable mitigations. Is
5992 off - Unconditionally disable mitigations. Is
5995 prctl - Indirect branch speculation is enabled,
6001 - Like "prctl" above, but only STIBP is
6007 - Same as "prctl" above, but all seccomp
6012 - Like "seccomp" above, but only STIBP is
6017 auto - Kernel selects the mitigation depending on
6028 off - Disable mitigation
6029 microcode - Enable microcode mitigation only
6030 safe-ret - Enable sw-only safe RET mitigation (default)
6031 ibpb - Enable mitigation by issuing IBPB on
6033 ibpb-vmexit - Issue IBPB only on VMEXIT
6034 (cloud-specific mitigation)
6059 on - Unconditionally disable Speculative Store Bypass
6060 off - Unconditionally enable Speculative Store Bypass
6061 auto - Kernel detects whether the CPU model contains an
6067 prctl - Control Speculative Store Bypass per thread
6071 seccomp - Same as "prctl" above, but all seccomp threads
6079 on,auto - On Power8 and Power9 insert a store-forwarding
6083 off - No action.
6102 off - not enabled
6104 warn - the kernel will emit rate-limited warnings
6112 fatal - the kernel will send SIGBUS to applications
6117 ratelimit:N -
6118 Set system wide rate limit to N bus locks
6137 Certain CPUs are vulnerable to an MDS-like
6155 large system, such that srcu_struct structures
6157 This kernel-boot parameter defaults to 128,
6158 but takes effect only when the low-order four
6175 instead of the compile-time CONFIG_NR_CPUS.
6179 grace-period sequence counter wrap for the
6180 srcu_data structure's ->srcu_gp_seq_needed field.
6195 Specifies the number of no-delay instances
6202 Specifies the per-grace-period phase, number of
6203 non-sleeping polls of readers. Beyond this limit,
6209 Specifies number of microseconds of non-sleeping
6210 delay between each non-sleeping poll of readers.
6213 Specifies the number of update-side contention
6218 set for contention-based conversions to occur.
6220 ssbd= [ARM64,HW]
6228 force-on: Unconditionally enable mitigation for
6230 force-off: Unconditionally disable mitigation for
6253 stacktrace_filter=[function-list]
6255 will trace at boot up. function-list is a comma-separated
6263 Set the STI (builtin display/keyboard on the HP-PARISC
6265 as the initial boot-console.
6325 to global on non-NUMA machines)
6339 mode before resuming the system (see
6348 swiotlb= [ARM,IA-64,PPC,MIPS,X86]
6350 <int> -- Number of I/O TLB slabs
6351 <int> -- Second integer after comma. Number of swiotlb
6354 force -- force using of bounce buffers even if they
6356 noforce -- Never use bounce buffers (for debugging)
6371 Ignore sysrq setting - this boot parameter will
6379 cache size. See Documentation/networking/ip-sysctl.rst
6386 Specify "mem" (for Suspend-to-RAM) or "standby" (for
6388 as the system sleep state during system startup with
6390 The system is woken from this state using a
6391 wakeup-capable RTC alarm.
6397 -1: disable all active trip points in all thermal zones
6401 -1: disable all critical trip points in all thermal zones
6408 -1: disable all passive trip points
6414 <deci-seconds>: poll all this frequency
6436 Prevent the CPU-hotplug component of torturing
6440 Dump the ftrace buffer at torture-test shutdown,
6444 with rotating-rust storage.
6449 disables verbose-printk() sleeping.
6452 Duration of each verbose-printk() sleep in jiffies.
6470 https://trustedcomputinggroup.org/resource/pc-client-platform-tpm-profile-ptp-specification/
6475 where the system hangs or reboots and does not give the
6492 the system to live lock.
6498 make the system inoperable.
6508 local - Use the per CPU time stamp counter
6512 global - Event time stamps are synchronize across
6515 counter - Simple counting of events (1, 2, ..)
6519 uptime - Use jiffies as the time stamp.
6520 perf - Use the same clock that perf uses.
6521 mono - Use ktime_get_mono_fast_ns() for time stamps.
6522 mono_raw - Use ktime_get_raw_fast_ns() for time
6524 boot - Use ktime_get_boot_fast_ns() for time stamps.
6528 trace_event=[event-list]
6530 to facilitate early boot debugging. The event-list is a
6531 comma-separated list of trace events to enable. See
6534 trace_instance=[instance-info]
6545 Note, the "<system*>:" portion is optional if the event is
6552 event, and all events under the "initcall" system.
6554 trace_options=[option-list]
6556 The option-list is a comma delimited list of options
6570 trace_trigger=[trigger-list]
6605 Can be used to control the default behavior of the system
6607 See Documentation/admin-guide/mm/transhuge.rst
6615 - "tpm"
6616 - "tee"
6617 - "caam"
6627 - "kernel"
6628 - the same value as trusted.source: "tpm" or "tee"
6629 - "default"
6638 high-resolution timer mode on older hardware, and in
6674 on - Enable TSX on the system. Although there are
6677 several previous speculation-related CVEs, and
6681 off - Disable TSX on the system. (Note that this
6689 auto - Disable TSX if X86_BUG_TAA is present,
6690 otherwise enable TSX on the system.
6694 See Documentation/admin-guide/hw-vuln/tsx_async_abort.rst
6700 Similar to Micro-architectural Data Sampling (MDS)
6715 full - Enable TAA mitigation on vulnerable CPUs
6718 full,nosmt - Enable TAA mitigation and disable SMT on
6721 vulnerable to cross-thread TAA attacks.
6722 off - Unconditionally disable TAA mitigation
6724 On MDS-affected machines, tsx_async_abort=off can be
6736 Documentation/admin-guide/hw-vuln/tsx_async_abort.rst
6742 See also Documentation/input/devices/joystick-parport.rst
6744 udbg-immortal [PPC] When debugging early kernel crashes that
6750 Set number of hash buckets for UDP/UDP-Lite connections
6752 uhci-hcd.ignore_oc=
6754 Some badly-designed motherboards generate lots of
6763 unwind_debug [X86-64]
6771 (default -1 = authorized (same as 1),
6777 for newly-detected USB devices (default 2). This
6805 [USB] Specifies timeout for the initial 64-byte
6812 [USB] A list of quirk entries to augment the built-in
6815 VendorID:ProductID:Flags. The IDs are 4-digit hex
6817 will change the built-in quirk; setting it if it is
6822 a 255-byte read);
6826 Set-Interface requests);
6845 (bInterval-1).
6883 usb-storage.delay_use=
6887 usb-storage.quirks=
6889 override the built-in unusual_devs list. List
6892 and Product ID values (4-digit hex numbers) and
6894 to a common usb-storage quirk flag as follows:
6936 medium is write-protected).
6945 1 - undefined instruction events
6946 2 - system calls
6947 4 - invalid data aborts
6948 8 - SIGSEGV faults
6949 16 - SIGBUS faults
6965 vdso32= [X86] Control the 32-bit vDSO
6966 vdso32=1: enable 32-bit VDSO
6967 vdso32=0 or vdso32=2: disable 32-bit VDSO
6977 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
6979 vector= [IA-64,SMP]
7011 vga= [BOOT,X86-32] Select a particular video mode
7013 Documentation/admin-guide/svga.rst.
7019 May slow down system boot speed, especially when
7028 - Disable all of the above options
7040 vmhalt= [KNL,S390] Perform z/VM CP command after system halt.
7049 vsyscall= [X86-64]
7052 code). Most statically-linked binaries and older
7067 might break your system.
7076 see VGA-softcursor.txt. Default: 2 = underline.
7081 This is a 16-member array composed of values
7082 ranging from 0-255.
7087 This is a 16-member array composed of values
7088 ranging from 0-255.
7093 This is a 16-member array composed of values
7094 ranging from 0-255.
7099 Set system-wide default UTF-8 mode for all tty's.
7100 Default is 1, i.e. UTF-8 mode is enabled for all
7105 Format=<-1|0|1>
7106 Set system-wide default for whether a cursor
7107 is shown on new VTs. Default is -1,
7112 vt.italic= [VT] Default color for italic text; 0-15.
7115 vt.underline= [VT] Default color for underlined text; 0-15.
7119 see Documentation/watchdog/watchdog-parameters.rst
7120 or other driver-specific files in the
7134 Format: <cpu-list>
7148 Per-cpu work items which run for longer than this
7151 them from noticeably delaying other per-cpu work
7160 Per-cpu workqueues are generally preferred because
7162 locality; unfortunately, per-cpu workqueues tend to
7165 Enabling this makes the per-cpu workqueues which
7177 "numa" and "system". Default is "cache". For more
7179 Documentation/core-api/workqueue.rst.
7192 forces round-robin CPU selection to flush out
7200 on - Enable writecombine, use WUC for ioremap_wc()
7201 off - Disable writecombine, use SUC for ioremap_wc()
7203 x2apic_phys [X86-64,APIC] Use x2apic physical mode instead of
7207 xen_512gb_limit [KNL,X86-64,XEN]
7217 ide-disks -- unplug primary master IDE devices
7218 aux-ide-disks -- unplug non-primary-master IDE devices
7219 nics -- unplug network devices
7220 all -- unplug all emulated devices (NICs and IDE disks)
7221 unnecessary -- unplugging emulated devices is
7224 never -- do not unplug even if version check succeeds
7232 Select whether to always use non-faulting (safe) MSR
7254 with /sys/devices/system/xen_memory/xen_memory0/scrub_pages.
7257 xen_timer_slop= [X86-64,XEN]
7282 preferred over the 2-level event handling, as it is
7299 xive.store-eoi=off [PPC]
7305 xhci-hcd.quirks [USB,KNL]