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-rw-r--r--Documentation/kernel-parameters.txt81
1 files changed, 73 insertions, 8 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index b9e9bd854298..8f441dab0396 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -343,6 +343,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
no: ACPI OperationRegions are not marked as reserved,
no further checks are performed.
+ acpi_no_memhotplug [ACPI] Disable memory hotplug. Useful for kdump
+ kernels.
+
add_efi_memmap [EFI; X86] Include EFI memory map in
kernel's map of available physical RAM.
@@ -463,6 +466,22 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
atkbd.softrepeat= [HW]
Use software keyboard repeat
+ audit= [KNL] Enable the audit sub-system
+ Format: { "0" | "1" } (0 = disabled, 1 = enabled)
+ 0 - kernel audit is disabled and can not be enabled
+ until the next reboot
+ unset - kernel audit is initialized but disabled and
+ will be fully enabled by the userspace auditd.
+ 1 - kernel audit is initialized and partially enabled,
+ storing at most audit_backlog_limit messages in
+ RAM until it is fully enabled by the userspace
+ auditd.
+ Default: unset
+
+ audit_backlog_limit= [KNL] Set the audit queue size limit.
+ Format: <int> (must be >=0)
+ Default: 64
+
baycom_epp= [HW,AX25]
Format: <io>,<mode>
@@ -515,7 +534,14 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
cgroup_disable= [KNL] Disable a particular controller
Format: {name of the controller(s) to disable}
- {Currently supported controllers - "memory"}
+ The effects of cgroup_disable=foo are:
+ - foo isn't auto-mounted if you mount all cgroups in
+ a single hierarchy
+ - foo isn't visible as an individually mountable
+ subsystem
+ {Currently only "memory" controller deal with this and
+ cut the overhead, others just disable the usage. So
+ only cgroup_disable=memory is actually worthy}
checkreqprot [SELINUX] Set initial checkreqprot flag value.
Format: { "0" | "1" }
@@ -774,6 +800,15 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
disable= [IPV6]
See Documentation/networking/ipv6.txt.
+ disable_cpu_apicid= [X86,APIC,SMP]
+ Format: <int>
+ The number of initial APIC ID for the
+ corresponding CPU to be disabled at boot,
+ mostly used for the kdump 2nd kernel to
+ disable BSP to wake up multiple CPUs without
+ causing system reset or hang due to sending
+ INIT from AP to BSP.
+
disable_ddw [PPC/PSERIES]
Disable Dynamic DMA Window support. Use this if
to workaround buggy firmware.
@@ -881,6 +916,14 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
The xen output can only be used by Xen PV guests.
+ edac_report= [HW,EDAC] Control how to report EDAC event
+ Format: {"on" | "off" | "force"}
+ on: enable EDAC to report H/W event. May be overridden
+ by other higher priority error reporting module.
+ off: disable H/W event reporting through EDAC.
+ force: enforce the use of EDAC to report H/W event.
+ default: on.
+
ekgdboc= [X86,KGDB] Allow early kernel console debugging
ekgdboc=kbd
@@ -890,6 +933,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
edd= [EDD]
Format: {"off" | "on" | "skip[mbr]"}
+ efi= [EFI]
+ Format: { "old_map" }
+ old_map [X86-64]: switch to the old ioremap-based EFI
+ runtime services mapping. 32-bit still uses this one by
+ default.
+
efi_no_storage_paranoia [EFI; X86]
Using this parameter you can use more than 50% of
your efi variable storage. Use this parameter only if
@@ -1013,7 +1062,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
debugfs files are removed at module unload time.
gpt [EFI] Forces disk with valid GPT signature but
- invalid Protective MBR to be treated as GPT.
+ invalid Protective MBR to be treated as GPT. If the
+ primary GPT is corrupted, it enables the backup/alternate
+ GPT to be used instead.
grcan.enable0= [HW] Configuration of physical interface 0. Determines
the "Enable 0" bit of the configuration register.
@@ -1415,6 +1466,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
Valid arguments: on, off
Default: on
+ kmemcheck= [X86] Boot-time kmemcheck enable/disable/one-shot mode
+ Valid arguments: 0, 1, 2
+ kmemcheck=0 (disabled)
+ kmemcheck=1 (enabled)
+ kmemcheck=2 (one-shot mode)
+ Default: 2 (one-shot mode)
+
kstack=N [X86] Print N words from the kernel stack
in oops dumps.
@@ -1994,6 +2052,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
noapic [SMP,APIC] Tells the kernel to not make use of any
IOAPICs that may be present in the system.
+ nokaslr [X86]
+ Disable kernel base offset ASLR (Address Space
+ Layout Randomization) if built into the kernel.
+
noautogroup Disable scheduler automatic task group creation.
nobats [PPC] Do not use BATs for mapping kernel lowmem
@@ -2627,7 +2689,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
for RCU-preempt, and "s" for RCU-sched, and "N"
is the CPU number. This reduces OS jitter on the
offloaded CPUs, which can be useful for HPC and
-
real-time workloads. It can also improve energy
efficiency for asymmetric multiprocessors.
@@ -2643,8 +2704,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
periodically wake up to do the polling.
rcutree.blimit= [KNL]
- Set maximum number of finished RCU callbacks to process
- in one batch.
+ Set maximum number of finished RCU callbacks to
+ process in one batch.
rcutree.rcu_fanout_leaf= [KNL]
Increase the number of CPUs assigned to each
@@ -2663,8 +2724,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
value is one, and maximum value is HZ.
rcutree.qhimark= [KNL]
- Set threshold of queued
- RCU callbacks over which batch limiting is disabled.
+ Set threshold of queued RCU callbacks beyond which
+ batch limiting is disabled.
rcutree.qlowmark= [KNL]
Set threshold of queued RCU callbacks below which
@@ -3063,7 +3124,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
controller if no parameter or 1 is given or disable
it if 0 is given (See Documentation/cgroups/memory.txt)
- swiotlb= [IA-64] Number of I/O TLB slabs
+ swiotlb= [ARM,IA-64,PPC,MIPS,X86]
+ Format: { <int> | force }
+ <int> -- Number of I/O TLB slabs
+ force -- force using of bounce buffers even if they
+ wouldn't be automatically used by the kernel
switches= [HW,M68k]