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authorJiri Kosina <jkosina@suse.cz>2013-12-19 09:08:03 -0500
committerJiri Kosina <jkosina@suse.cz>2013-12-19 09:08:32 -0500
commite23c34bb41da65f354fb7eee04300c56ee48f60c (patch)
tree549fbe449d55273b81ef104a9755109bf4ae7817 /Documentation/kernel-parameters.txt
parentb481c2cb3534c85dca625973b33eba15f9af3e4c (diff)
parent319e2e3f63c348a9b66db4667efa73178e18b17d (diff)
Merge branch 'master' into for-next
Sync with Linus' tree to be able to apply fixes on top of newer things in tree (efi-stub). Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Diffstat (limited to 'Documentation/kernel-parameters.txt')
-rw-r--r--Documentation/kernel-parameters.txt148
1 files changed, 102 insertions, 46 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 5589f4dbc12f..0ccd5fc038b1 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -480,6 +480,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
480 Format: <io>,<irq>,<mode> 480 Format: <io>,<irq>,<mode>
481 See header of drivers/net/hamradio/baycom_ser_hdx.c. 481 See header of drivers/net/hamradio/baycom_ser_hdx.c.
482 482
483 blkdevparts= Manual partition parsing of block device(s) for
484 embedded devices based on command line input.
485 See Documentation/block/cmdline-partition.txt
486
483 boot_delay= Milliseconds to delay each printk during boot. 487 boot_delay= Milliseconds to delay each printk during boot.
484 Values larger than 10 seconds (10000) are changed to 488 Values larger than 10 seconds (10000) are changed to
485 no delay (0). 489 no delay (0).
@@ -850,6 +854,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
850 854
851 earlyprintk= [X86,SH,BLACKFIN,ARM] 855 earlyprintk= [X86,SH,BLACKFIN,ARM]
852 earlyprintk=vga 856 earlyprintk=vga
857 earlyprintk=efi
853 earlyprintk=xen 858 earlyprintk=xen
854 earlyprintk=serial[,ttySn[,baudrate]] 859 earlyprintk=serial[,ttySn[,baudrate]]
855 earlyprintk=serial[,0x...[,baudrate]] 860 earlyprintk=serial[,0x...[,baudrate]]
@@ -863,7 +868,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
863 Append ",keep" to not disable it when the real console 868 Append ",keep" to not disable it when the real console
864 takes over. 869 takes over.
865 870
866 Only vga or serial or usb debug port at a time. 871 Only one of vga, efi, serial, or usb debug port can
872 be used at a time.
867 873
868 Currently only ttyS0 and ttyS1 may be specified by 874 Currently only ttyS0 and ttyS1 may be specified by
869 name. Other I/O ports may be explicitly specified 875 name. Other I/O ports may be explicitly specified
@@ -877,8 +883,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
877 Interaction with the standard serial driver is not 883 Interaction with the standard serial driver is not
878 very good. 884 very good.
879 885
880 The VGA output is eventually overwritten by the real 886 The VGA and EFI output is eventually overwritten by
881 console. 887 the real console.
882 888
883 The xen output can only be used by Xen PV guests. 889 The xen output can only be used by Xen PV guests.
884 890
@@ -1071,6 +1077,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
1071 VIA, nVidia) 1077 VIA, nVidia)
1072 verbose: show contents of HPET registers during setup 1078 verbose: show contents of HPET registers during setup
1073 1079
1080 hpet_mmap= [X86, HPET_MMAP] Allow userspace to mmap HPET
1081 registers. Default set by CONFIG_HPET_MMAP_DEFAULT.
1082
1074 hugepages= [HW,X86-32,IA-64] HugeTLB pages to allocate at boot. 1083 hugepages= [HW,X86-32,IA-64] HugeTLB pages to allocate at boot.
1075 hugepagesz= [HW,IA-64,PPC,X86-64] The size of the HugeTLB pages. 1084 hugepagesz= [HW,IA-64,PPC,X86-64] The size of the HugeTLB pages.
1076 On x86-64 and powerpc, this option can be specified 1085 On x86-64 and powerpc, this option can be specified
@@ -1188,15 +1197,24 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
1188 owned by uid=0. 1197 owned by uid=0.
1189 1198
1190 ima_hash= [IMA] 1199 ima_hash= [IMA]
1191 Format: { "sha1" | "md5" } 1200 Format: { md5 | sha1 | rmd160 | sha256 | sha384
1201 | sha512 | ... }
1192 default: "sha1" 1202 default: "sha1"
1193 1203
1204 The list of supported hash algorithms is defined
1205 in crypto/hash_info.h.
1206
1194 ima_tcb [IMA] 1207 ima_tcb [IMA]
1195 Load a policy which meets the needs of the Trusted 1208 Load a policy which meets the needs of the Trusted
1196 Computing Base. This means IMA will measure all 1209 Computing Base. This means IMA will measure all
1197 programs exec'd, files mmap'd for exec, and all files 1210 programs exec'd, files mmap'd for exec, and all files
1198 opened for read by uid=0. 1211 opened for read by uid=0.
1199 1212
1213 ima_template= [IMA]
1214 Select one of defined IMA measurements template formats.
1215 Formats: { "ima" | "ima-ng" }
1216 Default: "ima-ng"
1217
1200 init= [KNL] 1218 init= [KNL]
1201 Format: <full_path> 1219 Format: <full_path>
1202 Run specified binary instead of /sbin/init as init 1220 Run specified binary instead of /sbin/init as init
@@ -1364,7 +1382,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
1364 pages. In the event, a node is too small to have both 1382 pages. In the event, a node is too small to have both
1365 kernelcore and Movable pages, kernelcore pages will 1383 kernelcore and Movable pages, kernelcore pages will
1366 take priority and other nodes will have a larger number 1384 take priority and other nodes will have a larger number
1367 of kernelcore pages. The Movable zone is used for the 1385 of Movable pages. The Movable zone is used for the
1368 allocation of pages that may be reclaimed or moved 1386 allocation of pages that may be reclaimed or moved
1369 by the page migration subsystem. This means that 1387 by the page migration subsystem. This means that
1370 HugeTLB pages may not be allocated from this zone. 1388 HugeTLB pages may not be allocated from this zone.
@@ -1776,6 +1794,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
1776 that the amount of memory usable for all allocations 1794 that the amount of memory usable for all allocations
1777 is not too small. 1795 is not too small.
1778 1796
1797 movable_node [KNL,X86] Boot-time switch to enable the effects
1798 of CONFIG_MOVABLE_NODE=y. See mm/Kconfig for details.
1799
1779 MTD_Partition= [MTD] 1800 MTD_Partition= [MTD]
1780 Format: <name>,<region-number>,<size>,<offset> 1801 Format: <name>,<region-number>,<size>,<offset>
1781 1802
@@ -1905,6 +1926,18 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
1905 will be sent. 1926 will be sent.
1906 The default is to send the implementation identification 1927 The default is to send the implementation identification
1907 information. 1928 information.
1929
1930 nfs.recover_lost_locks =
1931 [NFSv4] Attempt to recover locks that were lost due
1932 to a lease timeout on the server. Please note that
1933 doing this risks data corruption, since there are
1934 no guarantees that the file will remain unchanged
1935 after the locks are lost.
1936 If you want to enable the kernel legacy behaviour of
1937 attempting to recover these locks, then set this
1938 parameter to '1'.
1939 The default parameter value of '0' causes the kernel
1940 not to attempt recovery of lost locks.
1908 1941
1909 nfsd.nfs4_disable_idmapping= 1942 nfsd.nfs4_disable_idmapping=
1910 [NFSv4] When set to the default of '1', the NFSv4 1943 [NFSv4] When set to the default of '1', the NFSv4
@@ -2590,7 +2623,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
2590 ramdisk_size= [RAM] Sizes of RAM disks in kilobytes 2623 ramdisk_size= [RAM] Sizes of RAM disks in kilobytes
2591 See Documentation/blockdev/ramdisk.txt. 2624 See Documentation/blockdev/ramdisk.txt.
2592 2625
2593 rcu_nocbs= [KNL,BOOT] 2626 rcu_nocbs= [KNL]
2594 In kernels built with CONFIG_RCU_NOCB_CPU=y, set 2627 In kernels built with CONFIG_RCU_NOCB_CPU=y, set
2595 the specified list of CPUs to be no-callback CPUs. 2628 the specified list of CPUs to be no-callback CPUs.
2596 Invocation of these CPUs' RCU callbacks will 2629 Invocation of these CPUs' RCU callbacks will
@@ -2603,7 +2636,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
2603 real-time workloads. It can also improve energy 2636 real-time workloads. It can also improve energy
2604 efficiency for asymmetric multiprocessors. 2637 efficiency for asymmetric multiprocessors.
2605 2638
2606 rcu_nocb_poll [KNL,BOOT] 2639 rcu_nocb_poll [KNL]
2607 Rather than requiring that offloaded CPUs 2640 Rather than requiring that offloaded CPUs
2608 (specified by rcu_nocbs= above) explicitly 2641 (specified by rcu_nocbs= above) explicitly
2609 awaken the corresponding "rcuoN" kthreads, 2642 awaken the corresponding "rcuoN" kthreads,
@@ -2614,126 +2647,145 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
2614 energy efficiency by requiring that the kthreads 2647 energy efficiency by requiring that the kthreads
2615 periodically wake up to do the polling. 2648 periodically wake up to do the polling.
2616 2649
2617 rcutree.blimit= [KNL,BOOT] 2650 rcutree.blimit= [KNL]
2618 Set maximum number of finished RCU callbacks to process 2651 Set maximum number of finished RCU callbacks to process
2619 in one batch. 2652 in one batch.
2620 2653
2621 rcutree.fanout_leaf= [KNL,BOOT] 2654 rcutree.rcu_fanout_leaf= [KNL]
2622 Increase the number of CPUs assigned to each 2655 Increase the number of CPUs assigned to each
2623 leaf rcu_node structure. Useful for very large 2656 leaf rcu_node structure. Useful for very large
2624 systems. 2657 systems.
2625 2658
2626 rcutree.jiffies_till_first_fqs= [KNL,BOOT] 2659 rcutree.jiffies_till_first_fqs= [KNL]
2627 Set delay from grace-period initialization to 2660 Set delay from grace-period initialization to
2628 first attempt to force quiescent states. 2661 first attempt to force quiescent states.
2629 Units are jiffies, minimum value is zero, 2662 Units are jiffies, minimum value is zero,
2630 and maximum value is HZ. 2663 and maximum value is HZ.
2631 2664
2632 rcutree.jiffies_till_next_fqs= [KNL,BOOT] 2665 rcutree.jiffies_till_next_fqs= [KNL]
2633 Set delay between subsequent attempts to force 2666 Set delay between subsequent attempts to force
2634 quiescent states. Units are jiffies, minimum 2667 quiescent states. Units are jiffies, minimum
2635 value is one, and maximum value is HZ. 2668 value is one, and maximum value is HZ.
2636 2669
2637 rcutree.qhimark= [KNL,BOOT] 2670 rcutree.qhimark= [KNL]
2638 Set threshold of queued 2671 Set threshold of queued
2639 RCU callbacks over which batch limiting is disabled. 2672 RCU callbacks over which batch limiting is disabled.
2640 2673
2641 rcutree.qlowmark= [KNL,BOOT] 2674 rcutree.qlowmark= [KNL]
2642 Set threshold of queued RCU callbacks below which 2675 Set threshold of queued RCU callbacks below which
2643 batch limiting is re-enabled. 2676 batch limiting is re-enabled.
2644 2677
2645 rcutree.rcu_cpu_stall_suppress= [KNL,BOOT] 2678 rcutree.rcu_idle_gp_delay= [KNL]
2646 Suppress RCU CPU stall warning messages.
2647
2648 rcutree.rcu_cpu_stall_timeout= [KNL,BOOT]
2649 Set timeout for RCU CPU stall warning messages.
2650
2651 rcutree.rcu_idle_gp_delay= [KNL,BOOT]
2652 Set wakeup interval for idle CPUs that have 2679 Set wakeup interval for idle CPUs that have
2653 RCU callbacks (RCU_FAST_NO_HZ=y). 2680 RCU callbacks (RCU_FAST_NO_HZ=y).
2654 2681
2655 rcutree.rcu_idle_lazy_gp_delay= [KNL,BOOT] 2682 rcutree.rcu_idle_lazy_gp_delay= [KNL]
2656 Set wakeup interval for idle CPUs that have 2683 Set wakeup interval for idle CPUs that have
2657 only "lazy" RCU callbacks (RCU_FAST_NO_HZ=y). 2684 only "lazy" RCU callbacks (RCU_FAST_NO_HZ=y).
2658 Lazy RCU callbacks are those which RCU can 2685 Lazy RCU callbacks are those which RCU can
2659 prove do nothing more than free memory. 2686 prove do nothing more than free memory.
2660 2687
2661 rcutorture.fqs_duration= [KNL,BOOT] 2688 rcutorture.fqs_duration= [KNL]
2662 Set duration of force_quiescent_state bursts. 2689 Set duration of force_quiescent_state bursts.
2663 2690
2664 rcutorture.fqs_holdoff= [KNL,BOOT] 2691 rcutorture.fqs_holdoff= [KNL]
2665 Set holdoff time within force_quiescent_state bursts. 2692 Set holdoff time within force_quiescent_state bursts.
2666 2693
2667 rcutorture.fqs_stutter= [KNL,BOOT] 2694 rcutorture.fqs_stutter= [KNL]
2668 Set wait time between force_quiescent_state bursts. 2695 Set wait time between force_quiescent_state bursts.
2669 2696
2670 rcutorture.irqreader= [KNL,BOOT] 2697 rcutorture.gp_exp= [KNL]
2671 Test RCU readers from irq handlers. 2698 Use expedited update-side primitives.
2672 2699
2673 rcutorture.n_barrier_cbs= [KNL,BOOT] 2700 rcutorture.gp_normal= [KNL]
2701 Use normal (non-expedited) update-side primitives.
2702 If both gp_exp and gp_normal are set, do both.
2703 If neither gp_exp nor gp_normal are set, still
2704 do both.
2705
2706 rcutorture.n_barrier_cbs= [KNL]
2674 Set callbacks/threads for rcu_barrier() testing. 2707 Set callbacks/threads for rcu_barrier() testing.
2675 2708
2676 rcutorture.nfakewriters= [KNL,BOOT] 2709 rcutorture.nfakewriters= [KNL]
2677 Set number of concurrent RCU writers. These just 2710 Set number of concurrent RCU writers. These just
2678 stress RCU, they don't participate in the actual 2711 stress RCU, they don't participate in the actual
2679 test, hence the "fake". 2712 test, hence the "fake".
2680 2713
2681 rcutorture.nreaders= [KNL,BOOT] 2714 rcutorture.nreaders= [KNL]
2682 Set number of RCU readers. 2715 Set number of RCU readers.
2683 2716
2684 rcutorture.onoff_holdoff= [KNL,BOOT] 2717 rcutorture.object_debug= [KNL]
2718 Enable debug-object double-call_rcu() testing.
2719
2720 rcutorture.onoff_holdoff= [KNL]
2685 Set time (s) after boot for CPU-hotplug testing. 2721 Set time (s) after boot for CPU-hotplug testing.
2686 2722
2687 rcutorture.onoff_interval= [KNL,BOOT] 2723 rcutorture.onoff_interval= [KNL]
2688 Set time (s) between CPU-hotplug operations, or 2724 Set time (s) between CPU-hotplug operations, or
2689 zero to disable CPU-hotplug testing. 2725 zero to disable CPU-hotplug testing.
2690 2726
2691 rcutorture.shuffle_interval= [KNL,BOOT] 2727 rcutorture.rcutorture_runnable= [BOOT]
2728 Start rcutorture running at boot time.
2729
2730 rcutorture.shuffle_interval= [KNL]
2692 Set task-shuffle interval (s). Shuffling tasks 2731 Set task-shuffle interval (s). Shuffling tasks
2693 allows some CPUs to go into dyntick-idle mode 2732 allows some CPUs to go into dyntick-idle mode
2694 during the rcutorture test. 2733 during the rcutorture test.
2695 2734
2696 rcutorture.shutdown_secs= [KNL,BOOT] 2735 rcutorture.shutdown_secs= [KNL]
2697 Set time (s) after boot system shutdown. This 2736 Set time (s) after boot system shutdown. This
2698 is useful for hands-off automated testing. 2737 is useful for hands-off automated testing.
2699 2738
2700 rcutorture.stall_cpu= [KNL,BOOT] 2739 rcutorture.stall_cpu= [KNL]
2701 Duration of CPU stall (s) to test RCU CPU stall 2740 Duration of CPU stall (s) to test RCU CPU stall
2702 warnings, zero to disable. 2741 warnings, zero to disable.
2703 2742
2704 rcutorture.stall_cpu_holdoff= [KNL,BOOT] 2743 rcutorture.stall_cpu_holdoff= [KNL]
2705 Time to wait (s) after boot before inducing stall. 2744 Time to wait (s) after boot before inducing stall.
2706 2745
2707 rcutorture.stat_interval= [KNL,BOOT] 2746 rcutorture.stat_interval= [KNL]
2708 Time (s) between statistics printk()s. 2747 Time (s) between statistics printk()s.
2709 2748
2710 rcutorture.stutter= [KNL,BOOT] 2749 rcutorture.stutter= [KNL]
2711 Time (s) to stutter testing, for example, specifying 2750 Time (s) to stutter testing, for example, specifying
2712 five seconds causes the test to run for five seconds, 2751 five seconds causes the test to run for five seconds,
2713 wait for five seconds, and so on. This tests RCU's 2752 wait for five seconds, and so on. This tests RCU's
2714 ability to transition abruptly to and from idle. 2753 ability to transition abruptly to and from idle.
2715 2754
2716 rcutorture.test_boost= [KNL,BOOT] 2755 rcutorture.test_boost= [KNL]
2717 Test RCU priority boosting? 0=no, 1=maybe, 2=yes. 2756 Test RCU priority boosting? 0=no, 1=maybe, 2=yes.
2718 "Maybe" means test if the RCU implementation 2757 "Maybe" means test if the RCU implementation
2719 under test support RCU priority boosting. 2758 under test support RCU priority boosting.
2720 2759
2721 rcutorture.test_boost_duration= [KNL,BOOT] 2760 rcutorture.test_boost_duration= [KNL]
2722 Duration (s) of each individual boost test. 2761 Duration (s) of each individual boost test.
2723 2762
2724 rcutorture.test_boost_interval= [KNL,BOOT] 2763 rcutorture.test_boost_interval= [KNL]
2725 Interval (s) between each boost test. 2764 Interval (s) between each boost test.
2726 2765
2727 rcutorture.test_no_idle_hz= [KNL,BOOT] 2766 rcutorture.test_no_idle_hz= [KNL]
2728 Test RCU's dyntick-idle handling. See also the 2767 Test RCU's dyntick-idle handling. See also the
2729 rcutorture.shuffle_interval parameter. 2768 rcutorture.shuffle_interval parameter.
2730 2769
2731 rcutorture.torture_type= [KNL,BOOT] 2770 rcutorture.torture_type= [KNL]
2732 Specify the RCU implementation to test. 2771 Specify the RCU implementation to test.
2733 2772
2734 rcutorture.verbose= [KNL,BOOT] 2773 rcutorture.verbose= [KNL]
2735 Enable additional printk() statements. 2774 Enable additional printk() statements.
2736 2775
2776 rcupdate.rcu_expedited= [KNL]
2777 Use expedited grace-period primitives, for
2778 example, synchronize_rcu_expedited() instead
2779 of synchronize_rcu(). This reduces latency,
2780 but can increase CPU utilization, degrade
2781 real-time latency, and degrade energy efficiency.
2782
2783 rcupdate.rcu_cpu_stall_suppress= [KNL]
2784 Suppress RCU CPU stall warning messages.
2785
2786 rcupdate.rcu_cpu_stall_timeout= [KNL]
2787 Set timeout for RCU CPU stall warning messages.
2788
2737 rdinit= [KNL] 2789 rdinit= [KNL]
2738 Format: <full_path> 2790 Format: <full_path>
2739 Run specified binary instead of /init from the ramdisk, 2791 Run specified binary instead of /init from the ramdisk,
@@ -3462,11 +3514,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
3462 default x2apic cluster mode on platforms 3514 default x2apic cluster mode on platforms
3463 supporting x2apic. 3515 supporting x2apic.
3464 3516
3465 x86_mrst_timer= [X86-32,APBT] 3517 x86_intel_mid_timer= [X86-32,APBT]
3466 Choose timer option for x86 Moorestown MID platform. 3518 Choose timer option for x86 Intel MID platform.
3467 Two valid options are apbt timer only and lapic timer 3519 Two valid options are apbt timer only and lapic timer
3468 plus one apbt timer for broadcast timer. 3520 plus one apbt timer for broadcast timer.
3469 x86_mrst_timer=apbt_only | lapic_and_apbt 3521 x86_intel_mid_timer=apbt_only | lapic_and_apbt
3470 3522
3471 xen_emul_unplug= [HW,X86,XEN] 3523 xen_emul_unplug= [HW,X86,XEN]
3472 Unplug Xen emulated devices 3524 Unplug Xen emulated devices
@@ -3480,6 +3532,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
3480 the unplug protocol 3532 the unplug protocol
3481 never -- do not unplug even if version check succeeds 3533 never -- do not unplug even if version check succeeds
3482 3534
3535 xen_nopvspin [X86,XEN]
3536 Disables the ticketlock slowpath using Xen PV
3537 optimizations.
3538
3483 xirc2ps_cs= [NET,PCMCIA] 3539 xirc2ps_cs= [NET,PCMCIA]
3484 Format: 3540 Format:
3485 <irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]] 3541 <irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]