diff options
Diffstat (limited to 'Documentation/kernel-parameters.txt')
| -rw-r--r-- | Documentation/kernel-parameters.txt | 116 |
1 files changed, 112 insertions, 4 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 949dddcfd17..ea8e5b48557 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -905,6 +905,24 @@ bytes respectively. Such letter suffixes can also be entirely omitted. gpt [EFI] Forces disk with valid GPT signature but invalid Protective MBR to be treated as GPT. + grcan.enable0= [HW] Configuration of physical interface 0. Determines + the "Enable 0" bit of the configuration register. + Format: 0 | 1 + Default: 0 + grcan.enable1= [HW] Configuration of physical interface 1. Determines + the "Enable 0" bit of the configuration register. + Format: 0 | 1 + Default: 0 + grcan.select= [HW] Select which physical interface to use. + Format: 0 | 1 + Default: 0 + grcan.txsize= [HW] Sets the size of the tx buffer. + Format: <unsigned int> such that (txsize & ~0x1fffc0) == 0. + Default: 1024 + grcan.rxsize= [HW] Sets the size of the rx buffer. + Format: <unsigned int> such that (rxsize & ~0x1fffc0) == 0. + Default: 1024 + hashdist= [KNL,NUMA] Large hashes allocated during boot are distributed across NUMA nodes. Defaults on for 64-bit NUMA, off otherwise. @@ -1304,6 +1322,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted. lapic [X86-32,APIC] Enable the local APIC even if BIOS disabled it. + lapic= [x86,APIC] "notscdeadline" Do not use TSC deadline + value for LAPIC timer one-shot implementation. Default + back to the programmable timer unit in the LAPIC. + lapic_timer_c2_ok [X86,APIC] trust the local apic timer in C2 power state. @@ -1358,6 +1380,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted. * nohrst, nosrst, norst: suppress hard, soft and both resets. + * rstonce: only attempt one reset during + hot-unplug link recovery + * dump_id: dump IDENTIFY data. If there are multiple matching configurations changing @@ -1590,6 +1615,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted. log everything. Information is printed at KERN_DEBUG so loglevel=8 may also need to be specified. + module.sig_enforce + [KNL] When CONFIG_MODULE_SIG is set, this means that + modules without (valid) signatures will fail to load. + Note that if CONFIG_MODULE_SIG_ENFORCE is set, that + is always true, so this option does nothing. + mousedev.tap_time= [MOUSE] Maximum time between finger touching and leaving touchpad surface for touch to be considered @@ -1727,6 +1758,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted. will be autodetected by the client, and it will fall back to using the idmapper. To turn off this behaviour, set the value to '0'. + nfs.nfs4_unique_id= + [NFS4] Specify an additional fixed unique ident- + ification string that NFSv4 clients can insert into + their nfs_client_id4 string. This is typically a + UUID that is generated at system install time. nfs.send_implementation_id = [NFSv4.1] Send client implementation identification @@ -1820,8 +1856,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted. noexec=on: enable non-executable mappings (default) noexec=off: disable non-executable mappings + nosmap [X86] + Disable SMAP (Supervisor Mode Access Prevention) + even if it is supported by processor. + nosmep [X86] - Disable SMEP (Supervisor Mode Execution Protection) + Disable SMEP (Supervisor Mode Execution Prevention) even if it is supported by processor. noexec32 [X86-64] @@ -1841,6 +1881,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted. and restore using xsave. The kernel will fallback to enabling legacy floating-point and sse state. + eagerfpu= [X86] + on enable eager fpu restore + off disable eager fpu restore + auto selects the default scheme, which automatically + enables eagerfpu restore for xsaveopt. + nohlt [BUGS=ARM,SH] Tells the kernel that the sleep(SH) or wfi(ARM) instruction doesn't work correctly and not to use it. This is also useful when using JTAG debugger. @@ -1960,6 +2006,20 @@ bytes respectively. Such letter suffixes can also be entirely omitted. nox2apic [X86-64,APIC] Do not enable x2APIC mode. + cpu0_hotplug [X86] Turn on CPU0 hotplug feature when + CONFIG_BOOTPARAM_HOTPLUG_CPU0 is off. + Some features depend on CPU0. Known dependencies are: + 1. Resume from suspend/hibernate depends on CPU0. + Suspend/hibernate will fail if CPU0 is offline and you + need to online CPU0 before suspend/hibernate. + 2. PIC interrupts also depend on CPU0. CPU0 can't be + removed if a PIC interrupt is detected. + It's said poweroff/reboot may depend on CPU0 on some + machines although I haven't seen such issues so far + after CPU0 is offline on a few tested machines. + If the dependencies are under your control, you can + turn on cpu0_hotplug. + nptcg= [IA-64] Override max number of concurrent global TLB purges which is reported from either PAL_VM_SUMMARY or SAL PALO. @@ -1972,6 +2032,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted. nr_uarts= [SERIAL] maximum number of UARTs to be registered. + numa_balancing= [KNL,X86] Enable or disable automatic NUMA balancing. + Allowed values are enable and disable + numa_zonelist_order= [KNL, BOOT] Select zonelist order for NUMA. one of ['zone', 'node', 'default'] can be specified This can be set from sysctl after boot. @@ -2370,6 +2433,27 @@ bytes respectively. Such letter suffixes can also be entirely omitted. ramdisk_size= [RAM] Sizes of RAM disks in kilobytes See Documentation/blockdev/ramdisk.txt. + rcu_nocbs= [KNL,BOOT] + In kernels built with CONFIG_RCU_NOCB_CPU=y, set + the specified list of CPUs to be no-callback CPUs. + Invocation of these CPUs' RCU callbacks will + be offloaded to "rcuoN" kthreads created for + that purpose. This reduces OS jitter on the + offloaded CPUs, which can be useful for HPC and + real-time workloads. It can also improve energy + efficiency for asymmetric multiprocessors. + + rcu_nocbs_poll [KNL,BOOT] + Rather than requiring that offloaded CPUs + (specified by rcu_nocbs= above) explicitly + awaken the corresponding "rcuoN" kthreads, + make these kthreads poll for callbacks. + This improves the real-time response for the + offloaded CPUs by relieving them of the need to + wake up the corresponding kthread, but degrades + energy efficiency by requiring that the kthreads + periodically wake up to do the polling. + rcutree.blimit= [KNL,BOOT] Set maximum number of finished RCU callbacks to process in one batch. @@ -2393,6 +2477,17 @@ bytes respectively. Such letter suffixes can also be entirely omitted. rcutree.rcu_cpu_stall_timeout= [KNL,BOOT] Set timeout for RCU CPU stall warning messages. + rcutree.jiffies_till_first_fqs= [KNL,BOOT] + Set delay from grace-period initialization to + first attempt to force quiescent states. + Units are jiffies, minimum value is zero, + and maximum value is HZ. + + rcutree.jiffies_till_next_fqs= [KNL,BOOT] + Set delay between subsequent attempts to force + quiescent states. Units are jiffies, minimum + value is one, and maximum value is HZ. + rcutorture.fqs_duration= [KNL,BOOT] Set duration of force_quiescent_state bursts. @@ -2646,9 +2741,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted. smart2= [HW] Format: <io1>[,<io2>[,...,<io8>]] - smp-alt-once [X86-32,SMP] On a hotplug CPU system, only - attempt to substitute SMP alternatives once at boot. - smsc-ircc2.nopnp [HW] Don't use PNP to discover SMC devices smsc-ircc2.ircc_cfg= [HW] Device configuration I/O port smsc-ircc2.ircc_sir= [HW] SIR base I/O port @@ -2827,6 +2919,22 @@ bytes respectively. Such letter suffixes can also be entirely omitted. to facilitate early boot debugging. See also Documentation/trace/events.txt + trace_options=[option-list] + [FTRACE] Enable or disable tracer options at boot. + The option-list is a comma delimited list of options + that can be enabled or disabled just as if you were + to echo the option name into + + /sys/kernel/debug/tracing/trace_options + + For example, to enable stacktrace option (to dump the + stack trace of each event), add to the command line: + + trace_options=stacktrace + + See also Documentation/trace/ftrace.txt "trace options" + section. + transparent_hugepage= [KNL] Format: [always|madvise|never] |