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-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.
Format: <io>,<irq>,<mode>
See header of drivers/net/hamradio/baycom_ser_hdx.c.
+ blkdevparts= Manual partition parsing of block device(s) for
+ embedded devices based on command line input.
+ See Documentation/block/cmdline-partition.txt
+
boot_delay= Milliseconds to delay each printk during boot.
Values larger than 10 seconds (10000) are changed to
no delay (0).
@@ -850,6 +854,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
earlyprintk= [X86,SH,BLACKFIN,ARM]
earlyprintk=vga
+ earlyprintk=efi
earlyprintk=xen
earlyprintk=serial[,ttySn[,baudrate]]
earlyprintk=serial[,0x...[,baudrate]]
@@ -863,7 +868,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
Append ",keep" to not disable it when the real console
takes over.
- Only vga or serial or usb debug port at a time.
+ Only one of vga, efi, serial, or usb debug port can
+ be used at a time.
Currently only ttyS0 and ttyS1 may be specified by
name. Other I/O ports may be explicitly specified
@@ -877,8 +883,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
Interaction with the standard serial driver is not
very good.
- The VGA output is eventually overwritten by the real
- console.
+ The VGA and EFI output is eventually overwritten by
+ the real console.
The xen output can only be used by Xen PV guests.
@@ -1071,6 +1077,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
VIA, nVidia)
verbose: show contents of HPET registers during setup
+ hpet_mmap= [X86, HPET_MMAP] Allow userspace to mmap HPET
+ registers. Default set by CONFIG_HPET_MMAP_DEFAULT.
+
hugepages= [HW,X86-32,IA-64] HugeTLB pages to allocate at boot.
hugepagesz= [HW,IA-64,PPC,X86-64] The size of the HugeTLB pages.
On x86-64 and powerpc, this option can be specified
@@ -1188,15 +1197,24 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
owned by uid=0.
ima_hash= [IMA]
- Format: { "sha1" | "md5" }
+ Format: { md5 | sha1 | rmd160 | sha256 | sha384
+ | sha512 | ... }
default: "sha1"
+ The list of supported hash algorithms is defined
+ in crypto/hash_info.h.
+
ima_tcb [IMA]
Load a policy which meets the needs of the Trusted
Computing Base. This means IMA will measure all
programs exec'd, files mmap'd for exec, and all files
opened for read by uid=0.
+ ima_template= [IMA]
+ Select one of defined IMA measurements template formats.
+ Formats: { "ima" | "ima-ng" }
+ Default: "ima-ng"
+
init= [KNL]
Format: <full_path>
Run specified binary instead of /sbin/init as init
@@ -1364,7 +1382,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
pages. In the event, a node is too small to have both
kernelcore and Movable pages, kernelcore pages will
take priority and other nodes will have a larger number
- of kernelcore pages. The Movable zone is used for the
+ of Movable pages. The Movable zone is used for the
allocation of pages that may be reclaimed or moved
by the page migration subsystem. This means that
HugeTLB pages may not be allocated from this zone.
@@ -1776,6 +1794,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
that the amount of memory usable for all allocations
is not too small.
+ movable_node [KNL,X86] Boot-time switch to enable the effects
+ of CONFIG_MOVABLE_NODE=y. See mm/Kconfig for details.
+
MTD_Partition= [MTD]
Format: <name>,<region-number>,<size>,<offset>
@@ -1905,6 +1926,18 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
will be sent.
The default is to send the implementation identification
information.
+
+ nfs.recover_lost_locks =
+ [NFSv4] Attempt to recover locks that were lost due
+ to a lease timeout on the server. Please note that
+ doing this risks data corruption, since there are
+ no guarantees that the file will remain unchanged
+ after the locks are lost.
+ If you want to enable the kernel legacy behaviour of
+ attempting to recover these locks, then set this
+ parameter to '1'.
+ The default parameter value of '0' causes the kernel
+ not to attempt recovery of lost locks.
nfsd.nfs4_disable_idmapping=
[NFSv4] When set to the default of '1', the NFSv4
@@ -2590,7 +2623,7 @@ 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]
+ rcu_nocbs= [KNL]
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
@@ -2603,7 +2636,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
real-time workloads. It can also improve energy
efficiency for asymmetric multiprocessors.
- rcu_nocb_poll [KNL,BOOT]
+ rcu_nocb_poll [KNL]
Rather than requiring that offloaded CPUs
(specified by rcu_nocbs= above) explicitly
awaken the corresponding "rcuoN" kthreads,
@@ -2614,126 +2647,145 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
energy efficiency by requiring that the kthreads
periodically wake up to do the polling.
- rcutree.blimit= [KNL,BOOT]
+ rcutree.blimit= [KNL]
Set maximum number of finished RCU callbacks to process
in one batch.
- rcutree.fanout_leaf= [KNL,BOOT]
+ rcutree.rcu_fanout_leaf= [KNL]
Increase the number of CPUs assigned to each
leaf rcu_node structure. Useful for very large
systems.
- rcutree.jiffies_till_first_fqs= [KNL,BOOT]
+ rcutree.jiffies_till_first_fqs= [KNL]
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]
+ rcutree.jiffies_till_next_fqs= [KNL]
Set delay between subsequent attempts to force
quiescent states. Units are jiffies, minimum
value is one, and maximum value is HZ.
- rcutree.qhimark= [KNL,BOOT]
+ rcutree.qhimark= [KNL]
Set threshold of queued
RCU callbacks over which batch limiting is disabled.
- rcutree.qlowmark= [KNL,BOOT]
+ rcutree.qlowmark= [KNL]
Set threshold of queued RCU callbacks below which
batch limiting is re-enabled.
- rcutree.rcu_cpu_stall_suppress= [KNL,BOOT]
- Suppress RCU CPU stall warning messages.
-
- rcutree.rcu_cpu_stall_timeout= [KNL,BOOT]
- Set timeout for RCU CPU stall warning messages.
-
- rcutree.rcu_idle_gp_delay= [KNL,BOOT]
+ rcutree.rcu_idle_gp_delay= [KNL]
Set wakeup interval for idle CPUs that have
RCU callbacks (RCU_FAST_NO_HZ=y).
- rcutree.rcu_idle_lazy_gp_delay= [KNL,BOOT]
+ rcutree.rcu_idle_lazy_gp_delay= [KNL]
Set wakeup interval for idle CPUs that have
only "lazy" RCU callbacks (RCU_FAST_NO_HZ=y).
Lazy RCU callbacks are those which RCU can
prove do nothing more than free memory.
- rcutorture.fqs_duration= [KNL,BOOT]
+ rcutorture.fqs_duration= [KNL]
Set duration of force_quiescent_state bursts.
- rcutorture.fqs_holdoff= [KNL,BOOT]
+ rcutorture.fqs_holdoff= [KNL]
Set holdoff time within force_quiescent_state bursts.
- rcutorture.fqs_stutter= [KNL,BOOT]
+ rcutorture.fqs_stutter= [KNL]
Set wait time between force_quiescent_state bursts.
- rcutorture.irqreader= [KNL,BOOT]
- Test RCU readers from irq handlers.
+ rcutorture.gp_exp= [KNL]
+ Use expedited update-side primitives.
- rcutorture.n_barrier_cbs= [KNL,BOOT]
+ rcutorture.gp_normal= [KNL]
+ Use normal (non-expedited) update-side primitives.
+ If both gp_exp and gp_normal are set, do both.
+ If neither gp_exp nor gp_normal are set, still
+ do both.
+
+ rcutorture.n_barrier_cbs= [KNL]
Set callbacks/threads for rcu_barrier() testing.
- rcutorture.nfakewriters= [KNL,BOOT]
+ rcutorture.nfakewriters= [KNL]
Set number of concurrent RCU writers. These just
stress RCU, they don't participate in the actual
test, hence the "fake".
- rcutorture.nreaders= [KNL,BOOT]
+ rcutorture.nreaders= [KNL]
Set number of RCU readers.
- rcutorture.onoff_holdoff= [KNL,BOOT]
+ rcutorture.object_debug= [KNL]
+ Enable debug-object double-call_rcu() testing.
+
+ rcutorture.onoff_holdoff= [KNL]
Set time (s) after boot for CPU-hotplug testing.
- rcutorture.onoff_interval= [KNL,BOOT]
+ rcutorture.onoff_interval= [KNL]
Set time (s) between CPU-hotplug operations, or
zero to disable CPU-hotplug testing.
- rcutorture.shuffle_interval= [KNL,BOOT]
+ rcutorture.rcutorture_runnable= [BOOT]
+ Start rcutorture running at boot time.
+
+ rcutorture.shuffle_interval= [KNL]
Set task-shuffle interval (s). Shuffling tasks
allows some CPUs to go into dyntick-idle mode
during the rcutorture test.
- rcutorture.shutdown_secs= [KNL,BOOT]
+ rcutorture.shutdown_secs= [KNL]
Set time (s) after boot system shutdown. This
is useful for hands-off automated testing.
- rcutorture.stall_cpu= [KNL,BOOT]
+ rcutorture.stall_cpu= [KNL]
Duration of CPU stall (s) to test RCU CPU stall
warnings, zero to disable.
- rcutorture.stall_cpu_holdoff= [KNL,BOOT]
+ rcutorture.stall_cpu_holdoff= [KNL]
Time to wait (s) after boot before inducing stall.
- rcutorture.stat_interval= [KNL,BOOT]
+ rcutorture.stat_interval= [KNL]
Time (s) between statistics printk()s.
- rcutorture.stutter= [KNL,BOOT]
+ rcutorture.stutter= [KNL]
Time (s) to stutter testing, for example, specifying
five seconds causes the test to run for five seconds,
wait for five seconds, and so on. This tests RCU's
ability to transition abruptly to and from idle.
- rcutorture.test_boost= [KNL,BOOT]
+ rcutorture.test_boost= [KNL]
Test RCU priority boosting? 0=no, 1=maybe, 2=yes.
"Maybe" means test if the RCU implementation
under test support RCU priority boosting.
- rcutorture.test_boost_duration= [KNL,BOOT]
+ rcutorture.test_boost_duration= [KNL]
Duration (s) of each individual boost test.
- rcutorture.test_boost_interval= [KNL,BOOT]
+ rcutorture.test_boost_interval= [KNL]
Interval (s) between each boost test.
- rcutorture.test_no_idle_hz= [KNL,BOOT]
+ rcutorture.test_no_idle_hz= [KNL]
Test RCU's dyntick-idle handling. See also the
rcutorture.shuffle_interval parameter.
- rcutorture.torture_type= [KNL,BOOT]
+ rcutorture.torture_type= [KNL]
Specify the RCU implementation to test.
- rcutorture.verbose= [KNL,BOOT]
+ rcutorture.verbose= [KNL]
Enable additional printk() statements.
+ rcupdate.rcu_expedited= [KNL]
+ Use expedited grace-period primitives, for
+ example, synchronize_rcu_expedited() instead
+ of synchronize_rcu(). This reduces latency,
+ but can increase CPU utilization, degrade
+ real-time latency, and degrade energy efficiency.
+
+ rcupdate.rcu_cpu_stall_suppress= [KNL]
+ Suppress RCU CPU stall warning messages.
+
+ rcupdate.rcu_cpu_stall_timeout= [KNL]
+ Set timeout for RCU CPU stall warning messages.
+
rdinit= [KNL]
Format: <full_path>
Run specified binary instead of /init from the ramdisk,
@@ -3462,11 +3514,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
default x2apic cluster mode on platforms
supporting x2apic.
- x86_mrst_timer= [X86-32,APBT]
- Choose timer option for x86 Moorestown MID platform.
+ x86_intel_mid_timer= [X86-32,APBT]
+ Choose timer option for x86 Intel MID platform.
Two valid options are apbt timer only and lapic timer
plus one apbt timer for broadcast timer.
- x86_mrst_timer=apbt_only | lapic_and_apbt
+ x86_intel_mid_timer=apbt_only | lapic_and_apbt
xen_emul_unplug= [HW,X86,XEN]
Unplug Xen emulated devices
@@ -3480,6 +3532,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
the unplug protocol
never -- do not unplug even if version check succeeds
+ xen_nopvspin [X86,XEN]
+ Disables the ticketlock slowpath using Xen PV
+ optimizations.
+
xirc2ps_cs= [NET,PCMCIA]
Format:
<irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]