Lines Matching +full:use +full:- +full:advanced +full:- +full:sector +full:- +full:protection
2 Advanced Configuration and Power Interface
5 force -- enable ACPI if default was off
6 on -- enable ACPI but allow fallback to DT [arm64]
7 off -- disable ACPI if default was on
8 noirq -- do not use ACPI for IRQ routing
9 strict -- Be less tolerant of platforms that are not
11 rsdt -- prefer RSDT over (default) XSDT
12 copy_dsdt -- copy DSDT to memory
20 2: use 2nd APIC table, if available
21 1,0: use 1st APIC table
26 If set to vendor, prefer vendor-specific driver
29 If set to video, use the ACPI video.ko driver.
30 If set to native, use the device's native backlight mode.
34 force FADT to use 32 bit addresses rather than the
36 bit addresses for force ACPI ignore these and use
58 Documentation/firmware-guide/acpi/debug.rst for more information about
106 use by PCI
116 Format: <byte> or <bitmap-list>
119 Disable auto-serialization of AML methods
122 auto-serialization feature.
140 Ignore the ACPI-based watchdog interface (WDAT) and let
161 acpi_osi=! # disable all built-in OS vendor
163 acpi_osi=!! # enable all built-in OS vendor
225 For broken nForce2 BIOS resulting in XT-PIC timer.
234 as soon as the kernel's real-mode entry point is called.
256 suspend and resume to be ignored (use wisely).
259 Use timer override. For some broken Nvidia NF5 boards
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
295 and you need to use tracing_snapshot() on boot up, and
296 do not want to use tracing_snapshot_alloc() as it needs
300 Allow execve() of 32-bit applications and setting of the
302 subset of the CPUs support 32-bit EL0. When this
303 parameter is present, the set of CPUs supporting 32-bit
305 and hot-unplug operations may be restricted.
307 See Documentation/arm64/asymmetric-32bit.rst for more
310 amd_iommu= [HW,X86-64]
313 fullflush - Deprecated, equivalent to iommu.strict=1
314 off - do not initialize any AMD IOMMU found in
316 force_isolation - Force device isolation for all
321 force_enable - Force enable the IOMMU on platforms known
322 to be buggy with IOMMU enabled. Use this
324 pgtbl_v1 - Use v1 page table for DMA-API (Default).
325 pgtbl_v2 - Use v2 page table for DMA-API.
327 amd_iommu_dump= [HW,X86-64]
333 amd_iommu_intr= [HW,X86-64]
336 legacy - Use legacy interrupt remapping mode.
337 vapic - Use virtual APIC mode, which allows IOMMU
339 This mode requires kvm-amd.avic=1.
353 Power management functions (SPARCstation-4/5 + deriv.)
355 Disable APC CPU standby support. SPARCstation-Fox does
356 not play well with APC CPU idle - disable it if you have
359 apic= [APIC,X86] Advanced Programmable Interrupt Controller
363 when initialising the APIC and IO-APIC components.
364 For X86-32, this can also be used to specify an APIC
381 show_lapic= [APIC,X86] Advanced Programmable Interrupt Controller
384 to set it to "all" by meaning -- no limit here.
390 apm= [APM] Advanced Power Management
393 arcrimi= [HW,NET] ARCnet - "RIM I" (entirely mem-mapped) cards
430 Use software keyboard repeat
432 audit= [KNL] Enable the audit sub-system
434 0 | off - kernel audit is disabled and can not be
436 unset - kernel audit is initialized but disabled and
438 1 | on - kernel audit is initialized and partially
451 0 - Disable the BAU.
452 1 - Enable the BAU.
453 unset - Disable the BAU.
480 See Documentation/block/cmdline-partition.rst
491 See Documentation/admin-guide/bootconfig.rst
496 bttv.pll= See Documentation/admin-guide/media/bttv.rst
499 bulk_remove=off [PPC] This parameter disables the use of the pSeries
505 cachesize= [BUGS=X86-32] Override level 2 CPU cache size detection.
524 inclusive. See arch/mips/include/asm/pgtable-bits.h
534 - foo isn't auto-mounted if you mount all cgroups in
536 - foo isn't visible as an individually mountable
538 - if foo is an optional feature then the feature is
544 Specifying "pressure" disables per-cgroup pressure
558 nosocket -- Disable socket memory accounting.
559 nokmem -- Disable kernel memory accounting.
564 0 -- check protection applied by kernel (includes
565 any implied execute protection).
566 1 -- check protection requested by application.
578 numbers X. Note the Linux-specific bits are not necessarily
579 stable over kernel options, but the vendor-specific
599 force such clocks to be always-on nor does it reserve
603 information, see Documentation/driver-api/clk.rst.
605 clock= [BUGS=X86-32, HW] gettimeofday clocksource override.
614 Override the default clocksource and use the clocksource
622 [X86-32] pit,hpet,tsc;
629 [X86-64] hpet,tsc
635 architected timer so that code using WFE-based polling
655 clocksource-wdtest.holdoff= [KNL]
661 cma=nn[MG]@[start[MG][-end[MG]]]
672 Sets the size of kernel per-numa memory area for
674 per-numa CMA altogether. And If this option is not
676 With per-numa CMA enabled, DMA users on node nid will
692 com20020= [HW,NET] ARCnet - COM20020 chipset
696 com90io= [HW,NET] ARCnet - COM90xx chipset (IO-mapped buffers)
700 ARCnet - COM90xx chipset (memory-mapped buffers)
708 tty<n> Use the virtual console device <n>.
712 Use the specified serial port. The options are of
718 See Documentation/admin-guide/serial-console.rst for more
728 Start an early, polled-mode console on the 8250/16550
731 MMIO inter-register address stride is either 8-bit
732 (mmio), 16-bit (mmio16), or 32-bit (mmio32).
736 the h/w is not re-initialized.
738 hvc<n> Use the hypervisor console device <n>. This is for
742 Use to disable console output, i.e., to have kernel
763 syscall, or to executing "dmesg -S --raw" or to reading
801 disable the cpuidle sub-system
804 [CPU_IDLE] Name of the cpuidle governor to use.
807 disable the cpufreq sub-system
811 policy to use. This governor must be registered in the
815 [X86] Delay for N microsec between assert and de-assert
821 Run kdump after running panic-notifiers and dumping
834 [KNL, X86-64] Select a region under 4G first, and
837 See Documentation/admin-guide/kdump/kdump.rst for further details.
842 start-[end] where start and end are both
844 Documentation/admin-guide/kdump/kdump.rst for an example.
847 [KNL, X86-64, ARM64] range could be above 4G. Allow kernel
854 [KNL, X86-64] range under 4G. When crashkernel=X,high
859 low memory is needed to make sure DMA buffers for 32-bit
875 [KNL] Disable crypto self-tests
883 csdlock_debug= [KNL] Enable debug add-ons of cross-CPU function call
899 See also Documentation/input/devices/joystick-parport.rst
905 boot sequence. If enabled, we use a weak hash instead
906 of siphash to hash pointers. Use this option if you are
909 insecure, please do not use on production kernels.
912 [KNL] verbose locking self-tests
915 self-tests.
917 (no extra messages), setting it to -1 (all bits set)
918 will print _a_lot_ more information - normally only
932 amount of memory for normal system use. The maximum
956 Format: { on, no-mount, off }
958 no-mount:
963 get a -EPERM as result when trying to register files
967 Default value is set in build-time with a kernel configuration.
979 Documentation/admin-guide/mm/hugetlbpage.rst.
993 delayacct [KNL] Enable per-task delay accounting
1035 Disables the use of 1TB hash page table segments. This
1052 Disable RADIX GTSE feature and use hcall for TLB
1069 Disable Dynamic DMA Window support. Use this
1097 entries for DMA-API debugging code. One entry is
1098 required per DMA-API allocation. Use this if the
1099 DMA-API debugging code disables itself because the
1103 With this option the DMA-API debugging driver
1121 Generic built-in EDID data sets are used, if one of
1126 available in Documentation/admin-guide/edid.rst. An EDID
1129 name. Each connector may use a unique EDID data
1138 Control how the dt_cpu_ftrs device-tree binding is
1141 off: Do not use it, fall back to legacy cpu table.
1148 what data is available or for reverse-engineering.
1153 Documentation/admin-guide/dynamic-debug-howto.rst
1156 nopku [X86] Disable Memory Protection Keys CPU feature found
1174 determined by stdout-path property in device tree's
1179 Start an early, polled-mode console on a Cadence
1190 Start an early, polled-mode console on the 8250/16550
1192 MMIO inter-register address stride is either 8-bit
1193 (mmio) or 32-bit (mmio32 or mmio32be).
1201 Start an early, polled-mode console on a pl011 serial
1205 the driver will use only 32-bit accessors to read/write
1214 Start an early, polled-mode console on a meson serial
1220 Start an early, polled-mode console on an msm serial
1226 Start an early, polled-mode console on an msm serial
1232 Start an early, polled-mode console on a serial port
1238 Start an early, polled-mode console on a serial port
1244 Use RISC-V SBI (Supervisor Binary Interface) for early
1247 smh Use ARM semihosting calls for early console.
1255 Use early console provided by serial driver available
1262 Start an early, polled-mode console on a lantiq serial
1269 Use early console provided by Freescale LP UART driver
1276 Start an early, polled-mode, output-only console on the
1281 Start an early, polled-mode console on the
1287 Start an early, polled-mode console on a Qualcomm
1295 coherent non-x86 systems that use system memory for
1300 Use early console provided by Freescale LINFlexD UART
1345 The optional "force" to "pciserial" enables use of a
1354 force: enforce the use of EDAC to report H/W event.
1382 Using this parameter you can use more than 50% of
1383 your efi variable storage. Use this parameter only if
1395 attribute is added to range 0x100000000-0x180000000 and
1396 0x10a0000000-0x1120000000.
1400 range 0x240000000-0x43fffffff.
1412 Documentation/admin-guide/acpi/ssdt-overlays.rst for details.
1429 elanfreq= [X86-32]
1437 See Documentation/admin-guide/kdump/kdump.rst for details.
1453 0 -- permissive (log only, no denials).
1454 1 -- enforcing (deny and log).
1486 See also Documentation/fault-injection/.
1490 See Documentation/admin-guide/sysctl/net.rst for
1494 See Documentation/admin-guide/blockdev/floppy.rst.
1497 [IA-64] Avoid check_sal_cache_flush which may hang on
1502 forcepae [X86-32]
1506 Warning: use of this parameter will taint the kernel
1529 ftrace_filter=[function-list]
1531 tracer at boot up. function-list is a comma-separated
1536 ftrace_notrace=[function-list]
1538 function-list. This list can be changed at run time
1542 ftrace_graph_filter=[function-list]
1545 function-list is a comma-separated list of functions
1549 ftrace_graph_notrace=[function-list]
1551 function-list. This list is a comma-separated list of
1571 off -- Don't create device links from firmware info.
1572 permissive -- Create device links from firmware info
1573 but use it only for ordering boot state clean
1575 on -- Create device links from firmware info and use it
1577 rpm -- Like "on", but also use to order runtime PM.
1588 See also Documentation/input/devices/joystick-parport.rst
1592 gart_fix_e820= [X86-64] disable the fix e820 for K8 GART
1596 gcov_persist= [GCOV] When non-zero (default), profiling data for
1603 Don't use this when you are not running on the
1606 gpio-mockup.gpio_mockup_ranges
1609 gpio-mockup.gpio_mockup_named_lines
1625 grcan.select= [HW] Select which physical interface to use.
1641 against bounds-checking flaws in the kernel's
1647 [KNL] Should the hard-lockup detector generate
1653 for 64-bit NUMA, off otherwise.
1656 hcl= [IA-64] SGI's Hardware Graph compatibility layer
1663 corresponding firmware-first mode error processing
1671 protect_image Turn on image protection during restoration
1673 during restoration read-only).
1699 hpet= [X86-32,HPET] option to control HPET usage
1702 disable: disable HPET and use PIT instead
1716 number of pages to allocate per-node can be specified.
1717 See also Documentation/admin-guide/mm/hugetlbpage.rst.
1728 Documentation/admin-guide/mm/hugetlbpage.rst.
1739 boot-time allocation of gigantic hugepages is skipped.
1767 by the CONFIG_BOOTPARAM_HUNG_TASK_PANIC build-time
1773 hvc_iucv_allow= [S390] Comma-separated list of z/VM user IDs.
1796 (disabled by default, and as a pre-condition
1798 i8042.direct [HW] Put keyboard port into non-translated mode
1808 i8042.nopnp [HW] Don't use ACPIPnP / PnPBIOS to discover KBD/AUX
1812 suspend-to-ram transitions, only during s2r
1836 -1 -- never invert brightness
1837 0 -- machine default
1838 1 -- force brightness inversion
1848 will use a lot of power and make the system run hot.
1852 idle=nomwait: Disable mwait for CPU C-states
1880 legacy only accept legacy-NaN binaries, if supported
1882 2008 only accept 2008-NaN binaries, if supported
1891 'relaxed' straps the emulator for both legacy-NaN and
1892 2008-NaN, whereas 'strict' enables legacy-NaN only on
1901 Ignore loglevel setting - this will print /all/
1919 ima_appraise_tcb [IMA] Deprecated. Use ima_policy= instead.
1924 Use the canonical format for the binary runtime
1960 ima_tcb [IMA] Deprecated. Use ima_policy= instead.
1968 Formats: { "ima" | "ima-ng" | "ima-ngv2" | "ima-sig" |
1969 "ima-sigv2" }
1970 Default: "ima-ng"
2002 initcall_blacklist= [KNL] Do not execute a comma-separated list of
2003 initcall functions. Useful for debugging built-in
2036 init_pkru= [X86] Specify the default memory protection keys rights
2048 0 -- basic integrity auditing messages. (Default)
2049 1 -- additional integrity auditing messages.
2060 this case, gfx device will use physical address for
2073 Disallow use of the Intel IOMMU scalable mode.
2077 could harm performance of some high-throughput
2086 1 to 9 specify maximum depth of C-state.
2093 Use intel_pstate as a scaling driver, but configure it
2096 used along with the hardware-managed P-states (HWP)
2100 in favor of acpi-cpufreq. Forcing the intel_pstate driver
2101 instead of acpi-cpufreq may disable platform features, such
2103 P-States information being indicated to OSPM and therefore
2106 or on platforms that use pcc-cpufreq instead of acpi-cpufreq.
2119 Allow per-logical-CPU P-State performance control limits using
2122 intremap= [X86-64, Intel-IOMMU]
2127 BIOS x2APIC opt-out request will be ignored
2151 0 - Try to allocate a 32-bit DMA address first, before
2153 1 - Allocate directly from the full usable range,
2155 greater than 32-bit addressing.
2159 0 - Lazy mode.
2160 Request that DMA unmap operations use deferred
2165 1 - Strict mode.
2168 unset - Use value of CONFIG_IOMMU_DEFAULT_DMA_{LAZY,STRICT}.
2170 legacy driver-specific options takes precedence.
2175 0 - Use IOMMU translation for DMA.
2176 1 - Bypass the IOMMU for DMA.
2177 unset - Use value of CONFIG_IOMMU_DEFAULT_PASSTHROUGH.
2179 io7= [HW] IO7 for Marvel-based Alpha systems
2194 See Documentation/admin-guide/nfs/nfsroot.rst.
2213 that use the kernel as a bootloader, and thus want
2218 Enables support for pseudo-NMIs in the kernel. This
2237 [Deprecated - use cpusets instead]
2238 Format: [flag-list,]<cpu-list>
2261 advised to use cpusets instead to disable scheduler load
2269 "number of CPUs in system - 1".
2295 The format of <cpu-list> is described above.
2299 ivrs_ioapic [HW,X86-64]
2300 Provide an override to the IOAPIC-ID<->DEVICE-ID
2304 * To map IOAPIC-ID decimal 10 to PCI device 00:14.0
2307 * To map IOAPIC-ID decimal 10 to PCI segment 0x1 and
2311 ivrs_hpet [HW,X86-64]
2312 Provide an override to the HPET-ID<->DEVICE-ID
2316 * To map HPET-ID decimal 0 to PCI device 00:14.0
2319 * To map HPET-ID decimal 10 to PCI segment 0x1 and
2323 ivrs_acpihid [HW,X86-64]
2324 Provide an override to the ACPI-HID:UID<->DEVICE-ID
2327 For example, to map UART-HID:UID AMD0020:0 to
2352 kernelcore= [KNL,X86,IA-64,PPC]
2355 the kernel for non-movable allocations. The requested
2365 subsystem. Note that allocations like PTEs-from-HighMem
2366 still use the HighMem zone if it exists, and the Normal
2373 for non-movable allocations and remaining memory is used
2384 gdb or control-c on the dbgp connection. When
2385 not using this parameter you use sysrq-g to break into
2390 or a supported polling keyboard driver (non-usb).
2400 characters and can work in polling mode, you can use
2401 this parameter to tell kgdb to use it as a backend
2417 Configure the RouterBoard 532 series on-chip
2420 kmemleak= [KNL] Boot-time kmemleak enable/disable
2426 kprobe_event=[probe-list]
2428 The probe-list is a semicolon delimited list of probe
2458 execution by eliminating the write-protection faults
2503 back to huge pages. If the value is a non-zero N, KVM will
2508 kvm-amd.nested= [KVM,AMD] Allow nested virtualization in KVM/SVM.
2511 kvm-amd.npt= [KVM,AMD] Disable nested paging (virtualized MMU)
2513 Default is 1 (enabled) if in 64-bit or 32-bit PAE mode.
2515 kvm-arm.mode=
2520 nvhe: Standard nVHE-based mode, without support for
2523 protected: nVHE-based mode with support for guests whose
2530 kvm-arm.vgic_v3_group0_trap=
2531 [KVM,ARM] Trap guest accesses to GICv3 group-0
2534 kvm-arm.vgic_v3_group1_trap=
2535 [KVM,ARM] Trap guest accesses to GICv3 group-1
2538 kvm-arm.vgic_v3_common_trap=
2542 kvm-arm.vgic_v4_enable=
2543 [KVM,ARM] Allow use of GICv4 for direct injection of
2554 kvm-intel.ept= [KVM,Intel] Disable extended page tables
2558 kvm-intel.emulate_invalid_guest_state=
2560 Ignored if kvm-intel.enable_unrestricted_guest=1, as
2566 kvm-intel.flexpriority=
2570 kvm-intel.nested=
2574 kvm-intel.unrestricted_guest=
2579 kvm-intel.vmentry_l1d_flush=[KVM,Intel] Mitigation for L1 Terminal Fault
2580 CVE-2018-3620.
2591 kvm-intel.vpid= [KVM,Intel] Disable Virtual Processor Identification
2610 on - enable the interface for the mitigation
2615 The kernel PTE inversion protection is unconditionally
2675 For details see: Documentation/admin-guide/hw-vuln/l1tf.rst
2681 lapic [X86-32,APIC] Enable the local APIC even if BIOS
2684 lapic= [X86,APIC] Do not use TSC deadline
2685 value for LAPIC timer one-shot implementation. Default
2704 libata.noacpi [LIBATA] Disables use of ACPI in libata suspend/resume
2708 libata.force= [LIBATA] Force configurations. The format is a comma-
2720 first fan-out link behind PMP device. It does not
2734 * Transfer mode: pio[0-7], mwdma[0-4] and udma[0-7].
2741 * rstonce: only attempt one reset during hot-unplug
2764 * atapi_mod16_dma: Enable the use of ATAPI DMA for
2767 * [no]dmalog: Enable or disable the use of the
2820 Set the number of locking read-acquisition kthreads.
2825 Set the number of locking write-acquisition kthreads.
2828 Set time (s) after boot for CPU-hotplug testing.
2831 Set time (s) between CPU-hotplug operations, or
2832 zero to disable CPU-hotplug testing.
2835 Set task-shuffle interval (jiffies). Shuffling
2836 tasks allows some CPUs to go into dyntick-idle
2841 is useful for hands-off automated testing.
2874 7 (KERN_DEBUG) debug-level messages
2884 logo.nologo [FB] Disables display of the built-in Linux logo.
2889 lp=0 [LP] Specify parallel ports to use, e.g,
2902 an IEEE 1284-compliant printer is attached; if
2908 time-consuming boot-time autodetection (up to 250 ms per
2929 machvec= [IA-64] Force the use of a particular machine-vector
2935 Example: machtype=lemote-yeeloong-2f-7inch
2937 max_addr=nn[KMG] [KNL,BOOT,IA-64] All physical memory greater
2950 (loop.max_loop) unconditionally pre-created at init time. The default
2953 devices can be requested on-demand with the
2954 /dev/loop-control interface.
2956 mce [X86-32] Machine Check Exception
2958 mce=option [X86-64] See Documentation/x86/x86_64/boot-options.rst
2961 See Documentation/admin-guide/md.rst.
2968 Control mitigation for the Micro-architectural Data
2983 full - Enable MDS mitigation on vulnerable CPUs
2984 full,nosmt - Enable MDS mitigation and disable
2986 off - Unconditionally disable MDS mitigation
2988 On TAA-affected machines, mds=off can be prevented by
2997 For details see: Documentation/admin-guide/hw-vuln/mds.rst
3011 [ARC,MICROBLAZE] - the limit applies only to low memory,
3014 [ARM64] - only limits memory covered by the linear
3017 [X86] Work as limiting max address. Use together
3027 [ARM,MIPS] - override the memory layout reported by
3034 mem=nopentium [BUGS=X86-32] Disable usage of 4MB pages for kernel
3041 per-device physically contiguous DMA buffers.
3049 See Documentation/admin-guide/mm/memory-hotplug.rst.
3074 Example: Exclude memory from 0x18690000-0x1869ffff
3088 memmap=<size>%<offset>-<oldtype>+<newtype>
3090 from <oldtype> to <newtype>. If "-<oldtype>" is left
3105 repeatable BIOS-originated corruption always
3106 affects the same memory, you can use memmap=
3112 use. Use this parameter to scan for
3117 seconds. Use this parameter to check at some
3149 mem_encrypt= [X86-64] AMD Secure Memory Encryption (SME) control
3157 Refer to Documentation/virt/kvm/x86/amd-memory-encryption.rst
3161 s2idle - Suspend-To-Idle
3162 shallow - Power-On Suspend or equivalent (if supported)
3163 deep - Suspend-To-RAM or equivalent (if supported)
3164 See Documentation/admin-guide/pm/sleep-states.rst.
3167 See Documentation/admin-guide/media/meye.rst.
3169 mfgpt_irq= [IA-32] Specify the IRQ to use for the
3170 Multi-Function General Purpose Timers on AMD Geode
3173 mfgptfix [X86-32] Fix MFGPT timers on AMD Geode platforms when
3180 min_addr=nn[KMG] [KNL,BOOT,IA-64] All physical memory below this
3187 0 - The attached screen is the 3.5" TFT
3188 1 - The attached screen is the 7" TFT
3189 2 - The VGA Shield is attached (1024x768)
3193 b - Enable backlight. The TFT backlight pin will be
3197 c - Enable the s3c camera interface.
3198 t - Reserved for enabling touchscreen support. The
3202 https://repo.or.cz/w/linux-2.6/mini2440.git
3207 arch-independent options, each of which is an
3208 aggregation of existing arch-specific options.
3221 ssbd=force-off [ARM64]
3243 have other ways of avoiding SMT-based attacks.
3278 full - Enable mitigation on vulnerable CPUs
3280 full,nosmt - Enable mitigation and disable SMT on
3283 off - Unconditionally disable mitigation
3296 Documentation/admin-guide/hw-vuln/processor_mmio_stale_data.rst
3299 [KNL] When set to true, modules will use async probing
3301 specific module, use the module specific control that
3313 module_blacklist= [KNL] Do not load a comma-separated list of
3327 movablecore= [KNL,X86,IA-64,PPC]
3338 movable_node [KNL] Boot-time switch to make hotplugable memory
3342 allocations. Use with caution!
3345 Format: <name>,<region-number>,<size>,<offset>
3348 <name>,<region-number>[,<base>,<size>,<buswidth>,<altbuswidth>]
3356 See arch/arm/mach-s3c/mach-jive.c
3359 [HW] Make the MicroTouch USB driver use raw coordinates
3379 multitce=off [PPC] This parameter disables the use of the pSeries
3388 something different and driver-specific.
3403 nfsaddrs= [NFS] Deprecated. Use ip= instead.
3404 See Documentation/admin-guide/nfs/nfsroot.rst.
3406 nfsroot= [NFS] nfs root filesystem for disk-less boxes.
3407 See Documentation/admin-guide/nfs/nfsroot.rst.
3410 See Documentation/admin-guide/nfs/nfsroot.rst.
3434 [NFS] enable 64-bit inode numbers.
3435 If zero, the NFS client will fake up a 32-bit inode
3437 of returning the full 64-bit number.
3438 The default is to return 64-bit inode numbers.
3458 scheme and the NFS level operations agree to use
3468 [NFS4] Specify an additional fixed unique ident-
3497 Setting this to value to 0 causes the kernel to use
3499 driver. A non-zero value sets the minimum interval
3504 server-to-server copies for which this server is
3509 server-to-server copy, knfsd temporarily mounts
3525 NMI stack-backtrace request.
3534 0 - turn hardlockup detector in nmi_watchdog off
3535 1 - turn hardlockup detector in nmi_watchdog on
3541 This is useful when you use a panic=... timeout and
3547 no387 [BUGS=X86-32] Tells the kernel to use the 387 maths
3551 no5lvl [X86-64] Disable 5-level paging mode. Forces
3552 kernel to use 4-level paging instead.
3567 it. Users could use console_suspend (usually
3583 caches in the slab allocator. Saves per-node memory,
3591 noapic [SMP,APIC] Tells the kernel to not make use of any
3602 no_entry_flush [PPC] Don't flush the L1-D cache when entering the kernel.
3604 noexec [IA-64]
3614 noexec32 [X86-64]
3615 This affects only 32-bit executables.
3616 noexec32=on: enable non-executable mappings (default)
3618 noexec32=off: disable non-executable mappings
3623 nofxsr [BUGS=X86-32] Disables x86 floating point extended
3625 legacy floating-point registers on task switch.
3647 nospectre_bhb [ARM64] Disable all mitigations for Spectre-BHB (branch
3655 [PPC] Don't flush the L1-D cache after accessing user data.
3659 enabling legacy floating-point and sse state.
3662 register states. The kernel will fall back to use
3670 form of xsave area. The kernel will fall back to use
3677 in do_idle() and not use the arch_cpu_idle()
3689 nohalt [IA-64] Tells the kernel not to use the power saving
3691 power-consumption. On the positive side, it reduces
3692 interrupt wake-up latency, which may improve performance
3694 real-time systems.
3704 compared. However, if this command-line option is
3707 debugging the kernel. Please do not use on production
3731 noirqdebug [X86-32] Disables the code which attempts to detect and
3742 nointremap [X86-64, Intel-IOMMU] Do not enable interrupt
3744 [Deprecated - use intremap=off]
3746 nointroute [IA-64]
3750 nojitter [IA-64] Disables jitter checking for ITC timers.
3752 no-kvmclock [X86,KVM] Disable paravirtualized KVM clock driver
3754 no-kvmapf [X86,KVM] Disable paravirtualized asynchronous page
3757 no-vmw-sched-clock
3759 clock and use the default one.
3761 no-steal-acc [X86,PV_OPS,ARM64,PPC/PSERIES] Disable paravirtualized
3765 nolapic [X86-32,APIC] Do not enable or use the local APIC.
3767 nolapic_timer [X86-32,APIC] Do not use the local APIC timer.
3769 nomca [IA-64] Disable machine check abort handling
3771 nomce [X86-32] Disable Machine Check Exception
3773 nomfgpt [X86-32] Disable Multi-Function General Purpose
3777 shutdown the other cpus. Instead use the REBOOT_VECTOR
3781 display-mode changes or accelerated rendering. Only the
3782 system framebuffer will be available for use if this was
3783 set-up by the firmware or boot loader.
3792 nopcid [X86-64] Disable the PCID cpu feature.
3794 norandmaps Don't use address space randomization. Equivalent to
3797 noreplace-smp [X86-32,SMP] Don't replace SMP instructions
3803 no-scroll [VGA] Disables scrollback.
3804 This is required for the Braillex ib80-piezo Braille
3807 nosbagart [IA-64]
3809 nosgx [X86-64,SGX] Disables Intel SGX kernel support.
3814 nosoftlockup [KNL] Disable the soft-lockup detector.
3819 soft-lockup and NMI watchdog (hard-lockup).
3823 nox2apic [X86-64,APIC] Do not enable x2APIC mode.
3838 nptcg= [IA-64] Override max number of concurrent global TLB
3847 n. So during boot up some boot time memory for per-cpu
3848 variables need be pre-allocated for later physical cpu
3863 See Documentation/admin-guide/sysctl/vm.rst for details.
3866 See Documentation/core-api/debugging-via-ohci1394.rst for more
3881 onenand.bdry= [HW,MTD] Flex-OneNAND Boundary Configuration
3885 boundary - index of last SLC block on Flex-OneNAND.
3887 lock - Configure if Flex-OneNAND boundary should be locked.
3901 running on a platform with a direct-mapped memory-side
3907 page_owner= [KNL] Boot-time page_owner enabling option.
3913 page_poison= [KNL] Boot-time parameter changing the state of
3923 reporting is disabled when it exceeds (MAX_ORDER-1).
3942 Use this option carefully, maybe worth to setup a
3954 See Documentation/admin-guide/tainted-kernels.rst for
3970 Use 'auto' to force the driver to use any
3992 Set to non-zero to probe primary and secondary ISA
3998 Set to non-zero if a chip is present that snoops speed
4021 bus and the use of other driver options may interfere
4040 bits to allow the use of the respective PIO modes.
4046 Set to non-zero to probe tertiary and further ISA
4052 platform configuration and the use of other driver
4062 Set to non-zero to probe QDI controllers. By default
4067 Set to non-zero to probe Winbond controllers. Use
4069 value given is the I/O port to use (typically 0x1b0).
4076 the use of the respective PIO modes. Bit 0 is for
4089 See also Documentation/admin-guide/blockdev/paride.rst.
4118 bios [X86-32] force use of PCI BIOS, don't access
4119 the hardware directly. Use this if your machine
4120 has a non-standard PCI host bridge.
4121 nobios [X86-32] disallow use of PCI BIOS, only direct
4122 hardware access methods are allowed. Use this
4125 conf1 [X86] Force use of PCI Configuration Access
4127 data in IO port 0xCFC, both 32-bit).
4128 conf2 [X86] Force use of PCI Configuration Access
4129 Mechanism 2 (IO port 0xCF8 is an 8-bit port for
4130 the function, IO port 0xCFA, also 8-bit, sets
4132 through ports 0xC000-0xCFFF).
4137 disable the use of PCIE advanced error reporting.
4139 root domains (aka PCI segments, in ACPI-speak).
4140 nommconf [X86] Disable use of MMCONFIG for PCI
4147 disable the use of MSI interrupts system-wide.
4152 primary IO-APIC for bridges that cannot disable
4159 biosirq [X86-32] Use PCI BIOS calls to get the interrupt
4168 Use with caution as certain devices share
4183 F0000h-100000h range.
4188 assign-busses [X86] Always assign all PCI bus
4197 noacpi [X86] Do not use ACPI for IRQ routing
4199 use_crs [X86] Use PCI host bridge window information
4201 is enabled by default. If you need to use this,
4204 If you need to use this, please report a bug.
4205 use_e820 [X86] Use E820 reservations to exclude parts of
4208 If you need to use this, please report a bug to
4209 <linux-pci@vger.kernel.org>.
4212 hardware. If you need to use this, please report
4213 a bug to <linux-pci@vger.kernel.org>.
4225 bfsort Sort PCI devices into breadth-first order.
4228 nobfsort Don't sort PCI devices into breadth-first order.
4230 tuning and use the BIOS-configured MPS defaults.
4240 configuration allows peer-to-peer DMA between
4243 that hot-added devices will work.
4258 A PCI-PCI bridge can be specified if resource
4264 for 4096-byte alignment.
4266 end-to-end CRC checking).
4267 bios: Use BIOS/firmware settings. This is the
4294 noari do not use PCIe ARI.
4295 noats [PCIE, Intel-IOMMU, AMD-IOMMU]
4296 do not use PCIe ATS (and IOMMU device IOTLB).
4316 nomio [S390] Do not use MIO instructions.
4317 norid [S390] ignore the RID field and force use of
4327 native Use native PCIe services (PME, AER, DPC, PCIe hotplug)
4329 use them. This may cause conflicts if the platform
4330 also tries to use these services.
4331 dpc-native Use native PCIe service for DPC only. May
4341 nomsi Do not use MSI for native PCIe PME signaling (this makes
4342 all PCIe root ports use INTx for all services).
4348 Keep all power-domains already enabled by bootloader on,
4354 See Documentation/admin-guide/blockdev/paride.rst.
4361 percpu_alloc= Select which percpu first chunk allocator to use.
4369 See Documentation/admin-guide/blockdev/paride.rst.
4372 See Documentation/admin-guide/blockdev/paride.rst.
4374 pirq= [SMP,APIC] Manual mp-table setup
4375 See Documentation/x86/i386/IO-APIC.rst.
4379 See also Documentation/admin-guide/parport.rst.
4398 CONFIG_PNP_DEBUG_MESSAGES option). Change at run-time
4407 { on | off | curr | res | no-curr | no-res }
4447 none - Limited to cond_resched() calls
4448 voluntary - Limited to cond_resched() and might_sleep() calls
4449 full - Any section that isn't explicitly preempt disabled
4452 print-fatal-signals=
4458 coredump - etc.
4461 you might want to try "ulimit -i unlimited".
4473 or lockdep-detected issues (only if lock debug is on).
4482 on - unlimited logging to /dev/kmsg from userspace
4483 off - logging to /dev/kmsg disabled
4484 ratelimit - ratelimit the logging
4491 Limit processor to maximum C-state
4495 Ignore the _CST method to determine C-states,
4502 Param: "schedule" - profile schedule points.
4503 Param: "sleep" - profile D-state sleeping (millisecs).
4505 Param: "kvm" - profile VM exits.
4506 Param: <number> - step/bucket size as a power of 2 for
4533 pstore.backend= Specify the name of the pstore backend to use
4536 See Documentation/admin-guide/blockdev/paride.rst.
4538 pti= [X86-64] Control Page Table Isolation of user and
4543 on - unconditionally enable
4544 off - unconditionally disable
4545 auto - kernel detects whether your CPU model is
4550 nopti [X86-64]
4554 [KNL] Number of legacy pty's. Overwrites compiled-in
4562 See Documentation/admin-guide/md.rst.
4565 See Documentation/admin-guide/blockdev/ramdisk.rst.
4570 [KNL] Enable or disable trusting the use of the
4576 [KNL] Enable or disable trusting the use of a
4586 cross-syscall address exposures. This is only
4592 ras=option[,option,...] [KNL] RAS-specific options
4598 rcu_nocbs[=cpu-list]
4603 enable the no-callback CPU mode, which prevents
4608 "p" for RCU-preempt, "s" for RCU-sched, and "g"
4612 and real-time workloads. It can also improve
4616 list of CPUs is set to no-callback mode from boot.
4620 no-callback mode from boot but the mode may be
4631 This improves the real-time response for the
4648 RCU grace-period cleanup.
4652 RCU grace-period initialization.
4656 RCU grace-period pre-initialization, that is,
4657 the propagation of recent CPU-hotplug changes up
4662 per-CPU rcuc kthreads. Defaults to a non-zero
4664 Specify rcutree.use_softirq=0 to use rcuc kthreads.
4674 cache-to-cache transfer latencies.
4680 and for NUMA systems with large remote-access
4693 Set the page-cache refill delay (in milliseconds)
4694 in response to low-memory conditions. The range
4698 Set delay from grace-period initialization to
4711 soliciting quiescent-state help from
4723 Set the SCHED_FIFO priority of the RCU per-CPU
4726 and for the RCU grace-period kthreads (rcu_bh,
4728 set, valid values are 1-99 and the default is 1
4729 (the least-favored priority). Otherwise, when
4730 RCU_BOOST is not set, valid values are 0-99 and
4731 the default is zero (non-realtime operation).
4736 Set the shift-right count to use to compute
4737 the callback-invocation batch limit bl from
4744 Please note that this callback-invocation batch
4745 limit applies only to non-offloaded callback
4751 On callback-offloaded (rcu_nocbs) CPUs,
4754 use of the ->nocb_bypass list. However, in the
4755 common non-flooded case, RCU queues directly to
4756 the main ->cblist in order to avoid the extra
4757 overhead of the ->nocb_bypass list and its lock.
4759 a single jiffy, RCU pre-queues the callbacks into
4760 the ->nocb_bypass queue. The definition of "too
4767 the wakeup overhead on the global grace-period
4769 each group's NOCB grace-period kthread.
4777 batch limiting is re-enabled.
4781 RCU's force-quiescent-state scan will aggressively
4789 Cause the grace-period kthread to get an extra
4791 it should at force-quiescent-state time.
4797 this specifies an rcu_read_unlock()-time delay
4800 catching RCU pointer leaks, that is, buggy use
4801 of RCU-protected pointers after the relevant
4811 grace-period primitives such as call_rcu().
4822 grace-period primitives.
4825 Set test-start holdoff period. The purpose of
4834 Test the double-argument variant of kfree_rcu().
4836 rcuscale.kfree_rcu_test_single, both the single-
4837 and double-argument variants are tested.
4840 Test the single-argument variant of kfree_rcu().
4842 rcuscale.kfree_rcu_test_double, both the single-
4843 and double-argument variants are tested.
4856 Set number of RCU readers. The value -1 selects
4858 "n" less than -1 selects N-n+1, where N is again
4859 the number of CPUs. For example, -2 selects N
4860 (the number of CPUs), -3 selects N+1, and so on.
4861 A value of "n" less than or equal to -N selects
4874 complete. This is useful for hands-off automated
4881 Write-side holdoff between grace periods,
4899 for RCU grace-period forward-progress testing
4906 Specify the fraction of a CPU-stall-warning
4907 period to do tight-loop forward-progress testing.
4911 forward-progress tests.
4915 need_resched() during tight-loop forward-progress
4919 Use conditional/asynchronous update-side
4923 Use expedited update-side primitives, if available.
4926 Use normal (non-expedited) asynchronous
4927 update-side primitives, if available.
4930 Use normal (non-expedited) synchronous
4931 update-side primitives, if available. If all
4935 they are all non-zero.
4943 Leak an RCU-protected pointer out of the reader.
4958 Set number of RCU callback-offload togglers.
4963 callback-offload toggling attempts.
4966 Set number of RCU readers. The value -1 selects
4967 N-1, where N is the number of CPUs. A value
4968 "n" less than -1 selects N-n-2, where N is again
4969 the number of CPUs. For example, -2 selects N
4970 (the number of CPUs), -3 selects N+1, and so on.
4973 Enable debug-object double-call_rcu() testing.
4976 Set time (s) after boot for CPU-hotplug testing.
4979 Set time (jiffies) between CPU-hotplug operations,
4980 or zero to disable CPU-hotplug testing.
4983 Set the number of read-then-exit kthreads used
4985 task-exit processing.
4988 The number of times in a given read-then-exit
4989 episode that a set of read-then-exit kthreads
4994 read-then-exit testing episodes.
4997 Set task-shuffle interval (s). Shuffling tasks
4998 allows some CPUs to go into dyntick-idle mode
5003 is useful for hands-off automated testing.
5012 to any other stall-related activity.
5022 grace-period kthread to test RCU CPU stall
5048 Test RCU's dyntick-idle handling. See also the
5086 Use expedited grace-period primitives, for
5090 real-time latency, and degrade energy efficiency.
5094 Use only normal grace-period primitives,
5097 real-time latency, CPU utilization, and
5099 increased grace-period latency. This parameter
5105 rcu_end_inkernel_boot() has been invoked), use
5106 only normal grace-period primitives. No effect
5112 post-boot attempt at an expedited RCU grace
5113 period to instead use normal non-expedited
5114 grace-period processing.
5122 set to the default value of -1.
5125 Set the minimum number of callback-queuing-time
5126 lock-contention events per jiffy required to
5127 cause the RCU Tasks flavors to switch to per-CPU
5130 the default value of -1.
5133 Set the number of callback queues to use for the
5135 of -1 allows this to be automatically (and
5137 for use in testing.
5143 number avoids disturbing real-time workloads,
5151 only printed prior to the stall-warning message
5184 force - Override the decision by the kernel to hide the
5194 E.g. to turn on cmt and turn off mba use:
5212 Set test-start holdoff period. The purpose of
5221 but the default has already reduced the per-pass
5226 Set number of readers. The default value of -1
5235 Set the read-side critical-section duration,
5239 Specify the read-protection implementation to test.
5258 See Documentation/admin-guide/cgroup-v1/cpusets.rst.
5262 Reserve I/O ports or memory so the kernel won't use
5266 reservetop= [X86-32]
5283 See Documentation/power/swsusp-and-swap-files.rst
5298 AMD-based UNRET and IBPB mitigations alone do not stop
5300 sibling threads. For that reason, STIBP is used on pro-
5304 off - no mitigation
5305 auto - automatically select a migitation
5306 auto,nosmt - automatically select a mitigation,
5310 ibpb - On AMD, mitigate short speculation
5315 ibpb,nosmt - Like "ibpb" above but will disable SMT
5319 unret - Force enable untrained return thunks,
5320 only effective on AMD f15h-f17h based
5322 unret,nosmt - Like unret, but will disable SMT when STIBP
5350 ro [KNL] Mount root device read-only on boot
5353 on Mark read-only kernel memory as read-only (default).
5354 off Leave read-only kernel memory writable for debugging.
5355 full Mark read-only kernel memory and aliases as read-only
5361 debug-uart get routed to the D+ and D- pins of the usb
5383 rw [KNL] Mount root device read-write on boot
5398 The default is 1 meaning that one can concurrently use
5404 cost of significant additional memory use for tables.
5435 to 10 seconds for built-in smp_call_function()
5442 that requesting even small non-zero numbers of
5449 The default of -1 specifies a number of kthreads
5454 test before initiating CPU-hotplug operations.
5458 CPU-hotplug operations. Specifying zero (which
5459 is the default) disables CPU-hotplug operations.
5465 Non-zero values are useful for automated tests.
5477 Use use_cpus_read_lock() instead of the default
5486 The probability weighting to use for the
5488 "wait" parameter. A value of -1 selects the
5489 default if all other weights are -1. However,
5491 value of -1 will instead select a weight of zero.
5494 The probability weighting to use for the
5496 non-zero "wait" parameter. See weight_single.
5499 The probability weighting to use for the
5507 The probability weighting to use for the
5509 non-zero "wait" parameter. See weight_single
5513 The probability weighting to use for the
5519 The probability weighting to use for the
5521 non-zero "wait" parameter. See weight_single
5528 0 -- disable. (may be 1 via CONFIG_CMDLINE="skew_tick=1"
5529 1 -- enable.
5540 0 -- disable.
5541 1 -- enable.
5547 0 -- disable.
5548 1 -- enable.
5551 serialnumber [BUGS=X86-32]
5553 sev=option[,option...] [X86-64] See Documentation/x86/x86_64/boot-options.rst
5558 simeth= [IA-64]
5590 may poison objects when not in use. Also tracks the
5633 using the csdlock_debug- kernel parameter.
5635 smsc-ircc2.nopnp [HW] Don't use PNP to discover SMC devices
5636 smsc-ircc2.ircc_cfg= [HW] Device configuration I/O port
5637 smsc-ircc2.ircc_sir= [HW] SIR base I/O port
5638 smsc-ircc2.ircc_fir= [HW] FIR base I/O port
5639 smsc-ircc2.ircc_irq= [HW] IRQ line
5640 smsc-ircc2.ircc_dma= [HW] DMA channel
5641 smsc-ircc2.ircc_transceiver= [HW] Transceiver type:
5647 CPUs) to use per physical CPU on systems capable of
5651 Default: -1 (no limit)
5654 [KNL] Should the soft-lockup detector generate panics.
5657 A value of 1 instructs the soft-lockup detector
5658 to panic the machine when a soft-lockup occurs. It is
5661 respective build-time switch to that functionality.
5664 [KNL] Should the soft-lockup detector generate
5669 See Documentation/admin-guide/laptops/sonypi.rst
5676 on - unconditionally enable, implies
5678 off - unconditionally disable, implies
5680 auto - kernel detects whether your CPU model is
5697 retpoline - replace indirect branches
5698 retpoline,generic - Retpolines
5699 retpoline,lfence - LFENCE; indirect branch
5700 retpoline,amd - alias for retpoline,lfence
5701 eibrs - enhanced IBRS
5702 eibrs,retpoline - enhanced IBRS + Retpolines
5703 eibrs,lfence - enhanced IBRS + LFENCE
5704 ibrs - use IBRS to protect kernel
5714 on - Unconditionally enable mitigations. Is
5717 off - Unconditionally disable mitigations. Is
5720 prctl - Indirect branch speculation is enabled,
5726 - Like "prctl" above, but only STIBP is
5732 - Same as "prctl" above, but all seccomp
5737 - Like "seccomp" above, but only STIBP is
5742 auto - Kernel selects the mitigation depending on
5773 on - Unconditionally disable Speculative Store Bypass
5774 off - Unconditionally enable Speculative Store Bypass
5775 auto - Kernel detects whether the CPU model contains an
5781 prctl - Control Speculative Store Bypass per thread
5785 seccomp - Same as "prctl" above, but all seccomp threads
5793 on,auto - On Power8 and Power9 insert a store-forwarding
5797 off - No action.
5816 off - not enabled
5818 warn - the kernel will emit rate-limited warnings
5826 fatal - the kernel will send SIGBUS to applications
5831 ratelimit:N -
5851 Certain CPUs are vulnerable to an MDS-like
5871 This kernel-boot parameter defaults to 128,
5872 but takes effect only when the low-order four
5889 instead of the compile-time CONFIG_NR_CPUS.
5893 grace-period sequence counter wrap for the
5894 srcu_data structure's ->srcu_gp_seq_needed field.
5909 Specifies the number of no-delay instances
5916 Specifies the per-grace-period phase, number of
5917 non-sleeping polls of readers. Beyond this limit,
5923 Specifies number of microseconds of non-sleeping
5924 delay between each non-sleeping poll of readers.
5927 Specifies the number of update-side contention
5932 set for contention-based conversions to occur.
5942 force-on: Unconditionally enable mitigation for
5944 force-off: Unconditionally disable mitigation for
5952 override the default stack gap protection. The value
5967 stacktrace_filter=[function-list]
5969 will trace at boot up. function-list is a comma-separated
5977 Set the STI (builtin display/keyboard on the HP-PARISC
5979 as the initial boot-console.
6029 to global on non-NUMA machines)
6038 amount of memory reserved for use by the client.
6049 This parameter controls use of the Protected
6052 swiotlb= [ARM,IA-64,PPC,MIPS,X86]
6054 <int> -- Number of I/O TLB slabs
6055 <int> -- Second integer after comma. Number of swiotlb
6058 force -- force using of bounce buffers even if they
6060 noforce -- Never use bounce buffers (for debugging)
6084 Ignore sysrq setting - this boot parameter will
6092 cache size. See Documentation/networking/ip-sysctl.rst
6099 Specify "mem" (for Suspend-to-RAM) or "standby" (for
6104 wakeup-capable RTC alarm.
6110 -1: disable all active trip points in all thermal zones
6114 -1: disable all critical trip points in all thermal zones
6125 -1: disable all passive trip points
6131 <deci-seconds>: poll all this frequency
6140 Specify if the kernel should make use of the cpu
6142 The scheduler will make use of this information and
6153 Prevent the CPU-hotplug component of torturing
6157 Dump the ftrace buffer at torture-test shutdown,
6161 with rotating-rust storage.
6166 disables verbose-printk() sleeping.
6169 Duration of each verbose-printk() sleep in jiffies.
6218 local - Use the per CPU time stamp counter
6222 global - Event time stamps are synchronize across
6225 counter - Simple counting of events (1, 2, ..)
6229 uptime - Use jiffies as the time stamp.
6230 perf - Use the same clock that perf uses.
6231 mono - Use ktime_get_mono_fast_ns() for time stamps.
6232 mono_raw - Use ktime_get_raw_fast_ns() for time
6234 boot - Use ktime_get_boot_fast_ns() for time stamps.
6238 trace_event=[event-list]
6240 to facilitate early boot debugging. The event-list is a
6241 comma-separated list of trace events to enable. See
6244 trace_options=[option-list]
6246 The option-list is a comma delimited list of options
6278 See Documentation/admin-guide/mm/transhuge.rst
6286 - "tpm"
6287 - "tee"
6288 - "caam"
6298 - "kernel"
6299 - the same value as trusted.source: "tpm" or "tee"
6300 - "default"
6309 high-resolution timer mode on older hardware, and in
6311 [x86] noirqtime: Do not use TSC to do irq accounting.
6323 tsc_early_khz= [X86] Skip early TSC calibration and use the given
6335 on - Enable TSX on the system. Although there are
6338 several previous speculation-related CVEs, and
6342 off - Disable TSX on the system. (Note that this
6350 auto - Disable TSX if X86_BUG_TAA is present,
6355 See Documentation/admin-guide/hw-vuln/tsx_async_abort.rst
6361 Similar to Micro-architectural Data Sampling (MDS)
6376 full - Enable TAA mitigation on vulnerable CPUs
6379 full,nosmt - Enable TAA mitigation and disable SMT on
6382 vulnerable to cross-thread TAA attacks.
6383 off - Unconditionally disable TAA mitigation
6385 On MDS-affected machines, tsx_async_abort=off can be
6397 Documentation/admin-guide/hw-vuln/tsx_async_abort.rst
6403 See also Documentation/input/devices/joystick-parport.rst
6405 udbg-immortal [PPC] When debugging early kernel crashes that
6411 Set number of hash buckets for UDP/UDP-Lite connections
6413 uhci-hcd.ignore_oc=
6415 Some badly-designed motherboards generate lots of
6426 (default -1 = authorized except for wireless USB,
6432 for newly-detected USB devices (default 2). This
6460 [USB] Specifies timeout for the initial 64-byte
6467 [USB] A list of quirk entries to augment the built-in
6470 VendorID:ProductID:Flags. The IDs are 4-digit hex
6472 will change the built-in quirk; setting it if it is
6477 a 255-byte read);
6481 Set-Interface requests);
6486 (e.g morph devices), don't use reset);
6500 (bInterval-1).
6535 usb-storage.delay_use=
6539 usb-storage.quirks=
6541 override the built-in unusual_devs list. List
6544 and Product ID values (4-digit hex numbers) and
6546 to a common usb-storage quirk flag as follows:
6552 device capacity by one sector);
6553 d = NO_READ_DISC_INFO (don't use
6555 e = NO_READ_CAPACITY_16 (don't use
6557 f = NO_REPORT_OPCODES (don't use report opcodes
6563 sector if the number is odd);
6566 j = NO_REPORT_LUNS (don't use report luns
6568 k = NO_SAME (do not use WRITE_SAME, uas only)
6588 medium is write-protected).
6597 1 - undefined instruction events
6598 2 - system calls
6599 4 - invalid data aborts
6600 8 - SIGSEGV faults
6601 16 - SIGBUS faults
6617 vdso32= [X86] Control the 32-bit vDSO
6618 vdso32=1: enable 32-bit VDSO
6619 vdso32=0 or vdso32=2: disable 32-bit VDSO
6629 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
6631 vector= [IA-64,SMP]
6652 <size> := size (can use standard suffixes
6663 vga= [BOOT,X86-32] Select a particular video mode
6665 Documentation/admin-guide/svga.rst.
6666 Use vga=ask for menu.
6680 - Disable all of the above options
6701 vsyscall= [X86-64]
6704 code). Most statically-linked binaries and older
6705 versions of glibc use these calls. Because these
6718 them quite hard to use for exploits but
6728 see VGA-softcursor.txt. Default: 2 = underline.
6733 This is a 16-member array composed of values
6734 ranging from 0-255.
6739 This is a 16-member array composed of values
6740 ranging from 0-255.
6745 This is a 16-member array composed of values
6746 ranging from 0-255.
6751 Set system-wide default UTF-8 mode for all tty's.
6752 Default is 1, i.e. UTF-8 mode is enabled for all
6757 Format=<-1|0|1>
6758 Set system-wide default for whether a cursor
6759 is shown on new VTs. Default is -1,
6764 vt.italic= [VT] Default color for italic text; 0-15.
6767 vt.underline= [VT] Default color for underlined text; 0-15.
6771 see Documentation/watchdog/watchdog-parameters.rst
6772 or other driver-specific files in the
6798 that this also can be controlled per-workqueue for
6802 Per-cpu workqueues are generally preferred because
6804 locality; unfortunately, per-cpu workqueues tend to
6807 Enabling this makes the per-cpu workqueues which
6822 forces round-robin CPU selection to flush out
6827 x2apic_phys [X86-64,APIC] Use x2apic physical mode instead of
6831 xen_512gb_limit [KNL,X86-64,XEN]
6833 to use only up to 512 GB of RAM. The reason to do so is
6841 ide-disks -- unplug primary master IDE devices
6842 aux-ide-disks -- unplug non-primary-master IDE devices
6843 nics -- unplug network devices
6844 all -- unplug all emulated devices (NICs and IDE disks)
6845 unnecessary -- unplugging emulated devices is
6848 never -- do not unplug even if version check succeeds
6856 Select whether to always use non-faulting (safe) MSR
6877 to Xen, for use by other domains. Can be also changed at runtime
6881 xen_timer_slop= [X86-64,XEN]
6906 preferred over the 2-level event handling, as it is
6908 much higher. Default is on (use fifo events).
6926 natively use the XIVE interrupt controller. This option
6933 xive.store-eoi=off [PPC]
6934 By default on POWER10 and above, the kernel will use
6936 is active. This option allows the XIVE driver to use
6939 xhci-hcd.quirks [USB,KNL]
6968 Use amd_pstate as a scaling driver, driver requests a