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-rw-r--r--Documentation/kernel-parameters.txt69
1 files changed, 55 insertions, 14 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 31e3377d8e14..b29f3c416296 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -329,6 +329,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
is a lot of faster
off - do not initialize any AMD IOMMU found in
the system
+ force_isolation - Force device isolation for all
+ devices. The IOMMU driver is not
+ allowed anymore to lift isolation
+ requirements as needed. This option
+ does not override iommu=pt
amijoy.map= [HW,JOY] Amiga joystick support
Map of devices attached to JOY0DAT and JOY1DAT
@@ -623,6 +628,25 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
no_debug_objects
[KNL] Disable object debugging
+ debug_guardpage_minorder=
+ [KNL] When CONFIG_DEBUG_PAGEALLOC is set, this
+ parameter allows control of the order of pages that will
+ be intentionally kept free (and hence protected) by the
+ buddy allocator. Bigger value increase the probability
+ of catching random memory corruption, but reduce the
+ amount of memory for normal system use. The maximum
+ possible value is MAX_ORDER/2. Setting this parameter
+ to 1 or 2 should be enough to identify most random
+ memory corruption problems caused by bugs in kernel or
+ driver code when a CPU writes to (or reads from) a
+ random memory location. Note that there exists a class
+ of memory corruptions problems caused by buggy H/W or
+ F/W or by drivers badly programing DMA (basically when
+ memory is written at bus level and the CPU MMU is
+ bypassed) which are not detectable by
+ CONFIG_DEBUG_PAGEALLOC, hence this option will not help
+ tracking down these problems.
+
debugpat [X86] Enable PAT debugging
decnet.addr= [HW,NET]
@@ -1059,7 +1083,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
nomerge
forcesac
soft
- pt [x86, IA-64]
+ pt [x86, IA-64]
+ group_mf [x86, IA-64]
+
io7= [HW] IO7 for Marvel based alpha systems
See comment before marvel_specify_io7 in
@@ -1178,9 +1204,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
kvm.ignore_msrs=[KVM] Ignore guest accesses to unhandled MSRs.
Default is 0 (don't ignore, but inject #GP)
- kvm.oos_shadow= [KVM] Disable out-of-sync shadow paging.
- Default is 1 (enabled)
-
kvm.mmu_audit= [KVM] This is a R/W parameter which allows audit
KVM MMU at runtime.
Default is 0 (off)
@@ -1630,12 +1653,17 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
The default is to return 64-bit inode numbers.
nfs.nfs4_disable_idmapping=
- [NFSv4] When set, this option disables the NFSv4
- idmapper on the client, but only if the mount
- is using the 'sec=sys' security flavour. This may
- make migration from legacy NFSv2/v3 systems easier
- provided that the server has the appropriate support.
- The default is to always enable NFSv4 idmapping.
+ [NFSv4] When set to the default of '1', this option
+ ensures that both the RPC level authentication
+ scheme and the NFS level operations agree to use
+ numeric uids/gids if the mount is using the
+ 'sec=sys' security flavour. In effect it is
+ disabling idmapping, which can make migration from
+ legacy NFSv2/v3 systems to NFSv4 easier.
+ Servers that do not support this mode of operation
+ 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'.
nmi_debug= [KNL,AVR32,SH] Specify one or more actions to take
when a NMI is triggered.
@@ -1796,6 +1824,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
nomfgpt [X86-32] Disable Multi-Function General Purpose
Timer usage (for AMD Geode machines).
+ nonmi_ipi [X86] Disable using NMI IPIs during panic/reboot to
+ shutdown the other cpus. Instead use the REBOOT_VECTOR
+ irq.
+
nopat [X86] Disable PAT (page attribute table extension of
pagetables) support.
@@ -2367,6 +2399,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
slram= [HW,MTD]
+ slab_max_order= [MM, SLAB]
+ Determines the maximum allowed order for slabs.
+ A high setting may cause OOMs due to memory
+ fragmentation. Defaults to 1 for systems with
+ more than 32MB of RAM, 0 otherwise.
+
slub_debug[=options[,slabs]] [MM, SLUB]
Enabling slub_debug allows one to determine the
culprit if slab objects become corrupted. Enabling
@@ -2645,6 +2683,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
[USB] Start with the old device initialization
scheme (default 0 = off).
+ usbcore.usbfs_memory_mb=
+ [USB] Memory limit (in MB) for buffers allocated by
+ usbfs (default = 16, 0 = max = 2047).
+
usbcore.use_both_schemes=
[USB] Try the other device initialization scheme
if the first one fails (default 1 = enabled).
@@ -2763,11 +2805,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
functions are at fixed addresses, they make nice
targets for exploits that can control RIP.
- emulate Vsyscalls turn into traps and are emulated
- reasonably safely.
+ emulate [default] Vsyscalls turn into traps and are
+ emulated reasonably safely.
- native [default] Vsyscalls are native syscall
- instructions.
+ native Vsyscalls are native syscall instructions.
This is a little bit faster than trapping
and makes a few dynamic recompilers work
better than they would in emulation mode.