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Diffstat (limited to 'Documentation/kernel-parameters.txt')
| -rw-r--r-- | Documentation/kernel-parameters.txt | 76 |
1 files changed, 59 insertions, 17 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index b4339e5a50da..eb93fd0ec734 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -315,12 +315,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted. CPU-intensive style benchmark, and it can vary highly in a microbenchmark depending on workload and compiler. - 1: only for 32-bit processes - 2: only for 64-bit processes + 32: only for 32-bit processes + 64: only for 64-bit processes on: enable for both 32- and 64-bit processes off: disable for both 32- and 64-bit processes - amd_iommu= [HW,X86-84] + amd_iommu= [HW,X86-64] Pass parameters to the AMD IOMMU driver in the system. Possible values are: fullflush - enable flushing of IO/TLB entries when @@ -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. @@ -1889,6 +1917,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted. arch_perfmon: [X86] Force use of architectural perfmon on Intel CPUs instead of the CPU specific event set. + timer: [X86] Force use of architectural NMI + timer mode (see also oprofile.timer + for generic hr timer mode) + [s390] Force legacy basic mode sampling + (report cpu_type "timer") oops=panic Always panic on oopses. Default is to just kill the process, but there is a small probability of @@ -2366,6 +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 @@ -2636,6 +2675,10 @@ 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). @@ -2754,11 +2797,10 @@ 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. |