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-rw-r--r--Documentation/kernel-parameters.txt83
1 files changed, 68 insertions, 15 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index eceda5e35..a4f4d693e 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -582,6 +582,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
bootmem_debug [KNL] Enable bootmem allocator debug messages.
+ bert_disable [ACPI]
+ Disable BERT OS support on buggy BIOSes.
+
bttv.card= [HW,V4L] bttv (bt848 + bt878 based grabber cards)
bttv.radio= Most important insmod options are available as
kernel args too.
@@ -687,6 +690,14 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
[SPARC64] tick
[X86-64] hpet,tsc
+ clocksource.arm_arch_timer.evtstrm=
+ [ARM,ARM64]
+ Format: <bool>
+ Enable/disable the eventstream feature of the ARM
+ architected timer so that code using WFE-based polling
+ loops can be debugged more effectively on production
+ systems.
+
clearcpuid=BITNUM [X86]
Disable CPUID feature X for the kernel. See
arch/x86/include/asm/cpufeatures.h for the valid bit
@@ -920,9 +931,18 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
dhash_entries= [KNL]
Set number of hash buckets for dentry cache.
+ disable_1tb_segments [PPC]
+ Disables the use of 1TB hash page table segments. This
+ causes the kernel to fall back to 256MB segments which
+ can be useful when debugging issues that require an SLB
+ miss to occur.
+
disable= [IPV6]
See Documentation/networking/ipv6.txt.
+ disable_radix [PPC]
+ Disable RADIX MMU mode on POWER9
+
disable_cpu_apicid= [X86,APIC,SMP]
Format: <int>
The number of initial APIC ID for the
@@ -1185,6 +1205,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
Address Range Mirroring feature even if your box
doesn't support it.
+ efivar_ssdt= [EFI; X86] Name of an EFI variable that contains an SSDT
+ that is to be dynamically loaded by Linux. If there are
+ multiple variables with the same name but with different
+ vendor GUIDs, all of them will be loaded. See
+ Documentation/acpi/ssdt-overlays.txt for details.
+
+
eisa_irq_edge= [PARISC,HW]
See header of drivers/parisc/eisa.c.
@@ -1803,12 +1830,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
js= [HW,JOY] Analog joystick
See Documentation/input/joystick.txt.
- kaslr/nokaslr [X86]
- Enable/disable kernel and module base offset ASLR
- (Address Space Layout Randomization) if built into
- the kernel. When CONFIG_HIBERNATION is selected,
- kASLR is disabled by default. When kASLR is enabled,
- hibernation will be disabled.
+ nokaslr [KNL]
+ When CONFIG_RANDOMIZE_BASE is set, this disables
+ kernel and module base offset ASLR (Address Space
+ Layout Randomization).
keepinitrd [HW,ARM]
@@ -2295,6 +2320,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
Note that if CONFIG_MODULE_SIG_FORCE is set, that
is always true, so this option does nothing.
+ module_blacklist= [KNL] Do not load a comma-separated list of
+ modules. Useful for debugging problem modules.
+
mousedev.tap_time=
[MOUSE] Maximum time between finger touching and
leaving touchpad surface for touch to be considered
@@ -2788,8 +2816,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
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
@@ -2998,12 +3024,18 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
resource_alignment=
Format:
[<order of align>@][<domain>:]<bus>:<slot>.<func>[; ...]
+ [<order of align>@]pci:<vendor>:<device>\
+ [:<subvendor>:<subdevice>][; ...]
Specifies alignment and device to reassign
aligned memory resources.
If <order of align> is not specified,
PAGE_SIZE is used as alignment.
PCI-PCI bridge can be specified, if resource
windows need to be expanded.
+ To specify the alignment for several
+ instances of a device, the PCI vendor,
+ device, subvendor, and subdevice may be
+ specified, e.g., 4096@pci:8086:9c22:103c:198f
ecrc= Enable/disable PCIe ECRC (transaction layer
end-to-end CRC checking).
bios: Use BIOS/firmware settings. This is the
@@ -3016,6 +3048,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
hpmemsize=nn[KMG] The fixed amount of bus space which is
reserved for hotplug bridge's memory window.
Default size is 2 megabytes.
+ hpbussize=nn The minimum amount of additional bus numbers
+ reserved for buses below a hotplug bridge.
+ Default is 1.
realloc= Enable/disable reallocating PCI bridge resources
if allocations done by BIOS are too small to
accommodate resources required by all child
@@ -3047,6 +3082,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
compat Treat PCIe ports as PCI-to-PCI bridges, disable the PCIe
ports driver.
+ pcie_port_pm= [PCIE] PCIe port power management handling:
+ off Disable power management of all PCIe ports
+ force Forcibly enable power management of all PCIe ports
+
pcie_pme= [PCIE,PM] Native PCIe PME signaling options:
nomsi Do not use MSI for native PCIe PME signaling (this makes
all PCIe root ports use INTx for all services).
@@ -3150,6 +3189,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
Format: <bool> (1/Y/y=enable, 0/N/n=disable)
default: disabled
+ printk.devkmsg={on,off,ratelimit}
+ Control writing to /dev/kmsg.
+ on - unlimited logging to /dev/kmsg from userspace
+ off - logging to /dev/kmsg disabled
+ ratelimit - ratelimit the logging
+ Default: ratelimit
+
printk.time= Show timing data prefixed to each printk message line
Format: <bool> (1/Y/y=enable, 0/N/n=disable)
@@ -3547,7 +3593,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
relax_domain_level=
[KNL, SMP] Set scheduler's default relax_domain_level.
- See Documentation/cgroups/cpusets.txt.
+ See Documentation/cgroup-v1/cpusets.txt.
relative_sleep_states=
[SUSPEND] Use sleep state labeling where the deepest
@@ -3594,6 +3640,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
present during boot.
nocompress Don't compress/decompress hibernation images.
no Disable hibernation and resume.
+ protect_image Turn on image protection during restoration
+ (that will set all pages holding image data
+ during restoration read-only).
retain_initrd [RAM] Keep initrd memory after extraction
@@ -3832,6 +3881,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
using these two parameters to set the minimum and
maximum port values.
+ sunrpc.svc_rpc_per_connection_limit=
+ [NFS,SUNRPC]
+ Limit the number of requests that the server will
+ process in parallel from a single connection.
+ The default value is 0 (no limit).
+
sunrpc.pool_mode=
[NFS]
Control how the NFS server code allocates CPUs to
@@ -3867,7 +3922,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
swapaccount=[0|1]
[KNL] Enable accounting of swap in memory resource
controller if no parameter or 1 is given or disable
- it if 0 is given (See Documentation/cgroups/memory.txt)
+ it if 0 is given (See Documentation/cgroup-v1/memory.txt)
swiotlb= [ARM,IA-64,PPC,MIPS,X86]
Format: { <int> | force }
@@ -3992,8 +4047,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
trace_event=[event-list]
[FTRACE] Set and start specified trace events in order
- to facilitate early boot debugging.
- See also Documentation/trace/events.txt
+ to facilitate early boot debugging. The event-list is a
+ comma separated list of trace events to enable. See
+ also Documentation/trace/events.txt
trace_options=[option-list]
[FTRACE] Enable or disable tracer options at boot.
@@ -4201,9 +4257,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
HIGHMEM regardless of setting
of CONFIG_HIGHPTE.
- uuid_debug= (Boolean) whether to enable debugging of TuxOnIce's
- uuid support.
-
vdso= [X86,SH]
On X86_32, this is an alias for vdso32=. Otherwise: