diff options
Diffstat (limited to 'Documentation/kernel-parameters.txt')
| -rw-r--r-- | Documentation/kernel-parameters.txt | 78 |
1 files changed, 59 insertions, 19 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index bfcb1a62a7b4..84960c66c77b 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -713,10 +713,18 @@ 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 +936,12 @@ 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 +958,15 @@ 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 +1054,7 @@ 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 +1062,7 @@ 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 @@ -1965,6 +1984,12 @@ 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 +2013,7 @@ 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 +2260,9 @@ 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 +2341,14 @@ 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 +2368,6 @@ 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 +2485,8 @@ 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 +2991,12 @@ 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 +3020,15 @@ 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 +3495,13 @@ 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 |