diff options
Diffstat (limited to 'Documentation/kernel-parameters.txt')
| -rw-r--r-- | Documentation/kernel-parameters.txt | 89 |
1 files changed, 69 insertions, 20 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index bfcb1a62a7b4..6726139bd289 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -165,7 +165,7 @@ multipliers 'Kilo', 'Mega', and 'Giga', equalling 2^10, 2^20, and 2^30 bytes respectively. Such letter suffixes can also be entirely omitted. - acpi= [HW,ACPI,X86] + acpi= [HW,ACPI,X86,ARM64] Advanced Configuration and Power Interface Format: { force | off | strict | noirq | rsdt } force -- enable ACPI if default was off @@ -175,6 +175,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted. strictly ACPI specification compliant. rsdt -- prefer RSDT over (default) XSDT copy_dsdt -- copy DSDT to memory + For ARM64, ONLY "acpi=off" or "acpi=force" are available See also Documentation/power/runtime_pm.txt, pci=noacpi @@ -713,10 +714,18 @@ bytes respectively. Such letter suffixes can also be entirely omitted. uart[8250],io,<addr>[,options] uart[8250],mmio,<addr>[,options] + uart[8250],mmio32,<addr>[,options] + uart[8250],0x<addr>[,options] Start an early, polled-mode console on the 8250/16550 UART at the specified I/O port or MMIO address, - switching to the matching ttyS device later. The - options are the same as for ttyS, above. + switching to the matching ttyS device later. + MMIO inter-register address stride is either 8-bit + (mmio) or 32-bit (mmio32). + If none of [io|mmio|mmio32], <addr> is assumed to be + equivalent to 'mmio'. 'options' are specified in the + same format described for ttyS above; if unspecified, + the h/w is not re-initialized. + hvc<n> Use the hypervisor console device <n>. This is for both Xen and PowerPC hypervisors. @@ -928,6 +937,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted. Enable debug messages at boot time. See Documentation/dynamic-debug-howto.txt for details. + eagerfpu= [X86] + on enable eager fpu restore + off disable eager fpu restore + auto selects the default scheme, which automatically + enables eagerfpu restore for xsaveopt. + early_ioremap_debug [KNL] Enable debug messages in early_ioremap support. This is useful for tracking down temporary early mappings @@ -944,11 +959,15 @@ bytes respectively. Such letter suffixes can also be entirely omitted. uart[8250],io,<addr>[,options] uart[8250],mmio,<addr>[,options] uart[8250],mmio32,<addr>[,options] + uart[8250],0x<addr>[,options] Start an early, polled-mode console on the 8250/16550 UART at the specified I/O port or MMIO address. MMIO inter-register address stride is either 8-bit (mmio) or 32-bit (mmio32). - The options are the same as for ttyS, above. + If none of [io|mmio|mmio32], <addr> is assumed to be + equivalent to 'mmio'. 'options' are specified in the + same format described for "console=ttyS<n>"; if + unspecified, the h/w is not initialized. pl011,<addr> Start an early, polled-mode console on a pl011 serial @@ -1036,7 +1055,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted. Format: {"off" | "on" | "skip[mbr]"} efi= [EFI] - Format: { "old_map", "nochunk", "noruntime" } + Format: { "old_map", "nochunk", "noruntime", "debug" } old_map [X86-64]: switch to the old ioremap-based EFI runtime services mapping. 32-bit still uses this one by default. @@ -1044,6 +1063,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted. boot stub, as chunking can cause problems with some firmware implementations. noruntime : disable EFI runtime services support + debug: enable misc debug output efi_no_storage_paranoia [EFI; X86] Using this parameter you can use more than 50% of @@ -1461,6 +1481,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted. By default, super page will be supported if Intel IOMMU has the capability. With this option, super page will not be supported. + ecs_off [Default Off] + By default, extended context tables will be supported if + the hardware advertises that it has support both for the + extended tables themselves, and also PASID support. With + this option set, extended tables will not be used even + on hardware which claims to support them. intel_idle.max_cstate= [KNL,HW,ACPI,X86] 0 disables intel_idle and fall back on acpi_idle. @@ -1965,6 +1991,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted. or memmap=0x10000$0x18690000 + memmap=nn[KMG]!ss[KMG] + [KNL,X86] Mark specific memory as protected. + Region of memory to be used, from ss to ss+nn. + The memory region may be marked as e820 type 12 (0xc) + and is NVDIMM or ADR memory. + memory_corruption_check=0/1 [X86] Some BIOSes seem to corrupt the first 64k of memory when doing things like suspend/resume. @@ -1988,7 +2020,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted. seconds. Use this parameter to check at some other rate. 0 disables periodic checking. - memtest= [KNL,X86] Enable memtest + memtest= [KNL,X86,ARM] Enable memtest Format: <integer> default : 0 <disable> Specifies the number of memtest passes to be @@ -2235,8 +2267,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted. nmi_watchdog= [KNL,BUGS=X86] Debugging features for SMP kernels Format: [panic,][nopanic,][num] - Valid num: 0 + Valid num: 0 or 1 0 - turn nmi_watchdog off + 1 - turn nmi_watchdog on When panic is specified, panic when an NMI watchdog timeout occurs (or 'nopanic' to override the opposite default). @@ -2315,12 +2348,14 @@ bytes respectively. Such letter suffixes can also be entirely omitted. noexec32=off: disable non-executable mappings read implies executable mappings - nofpu [SH] Disable hardware FPU at boot time. + nofpu [MIPS,SH] Disable hardware FPU at boot time. nofxsr [BUGS=X86-32] Disables x86 floating point extended register save and restore. The kernel will only save legacy floating-point registers on task switch. + nohugeiomap [KNL,x86] Disable kernel huge I/O mappings. + noxsave [BUGS=X86] Disables x86 extended register state save and restore using xsave. The kernel will fallback to enabling legacy floating-point and sse state. @@ -2340,12 +2375,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted. parameter, xsave area per process might occupy more memory on xsaves enabled systems. - 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. @@ -2463,7 +2492,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted. nousb [USB] Disable the USB subsystem - nowatchdog [KNL] Disable the lockup detector (NMI watchdog). + nowatchdog [KNL] Disable both lockup detectors, i.e. + soft-lockup and NMI watchdog (hard-lockup). nowb [ARM] @@ -2968,6 +2998,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted. Set maximum number of finished RCU callbacks to process in one batch. + rcutree.gp_init_delay= [KNL] + Set the number of jiffies to delay each step of + RCU grace-period initialization. This only has + effect when CONFIG_RCU_TORTURE_TEST_SLOW_INIT is + set. + rcutree.rcu_fanout_leaf= [KNL] Increase the number of CPUs assigned to each leaf rcu_node structure. Useful for very large @@ -2991,11 +3027,15 @@ bytes respectively. Such letter suffixes can also be entirely omitted. value is one, and maximum value is HZ. rcutree.kthread_prio= [KNL,BOOT] - Set the SCHED_FIFO priority of the RCU - per-CPU kthreads (rcuc/N). This value is also - used for the priority of the RCU boost threads - (rcub/N). Valid values are 1-99 and the default - is 1 (the least-favored priority). + Set the SCHED_FIFO priority of the RCU per-CPU + kthreads (rcuc/N). This value is also used for + the priority of the RCU boost threads (rcub/N) + and for the RCU grace-period kthreads (rcu_bh, + rcu_preempt, and rcu_sched). If RCU_BOOST is + set, valid values are 1-99 and the default is 1 + (the least-favored priority). Otherwise, when + RCU_BOOST is not set, valid values are 0-99 and + the default is zero (non-realtime operation). rcutree.rcu_nocb_leader_stride= [KNL] Set the number of NOCB kthread groups, which @@ -3462,6 +3502,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted. improve throughput, but will also increase the amount of memory reserved for use by the client. + suspend.pm_test_delay= + [SUSPEND] + Sets the number of seconds to remain in a suspend test + mode before resuming the system (see + /sys/power/pm_test). Only available when CONFIG_PM_DEBUG + is set. Default value is 5. + swapaccount=[0|1] [KNL] Enable accounting of swap in memory resource controller if no parameter or 1 is given or disable @@ -3746,6 +3793,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted. READ_CAPACITY_16 command); f = NO_REPORT_OPCODES (don't use report opcodes command, uas only); + g = MAX_SECTORS_240 (don't transfer more than + 240 sectors at a time, uas only); h = CAPACITY_HEURISTICS (decrease the reported device capacity by one sector if the number is odd); |
