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-rw-r--r--Documentation/kernel-parameters.txt78
1 files changed, 75 insertions, 3 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 551ecf09c8dd..ecc74fa4bfde 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -193,6 +193,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
(e.g. thinkpad_acpi, sony_acpi, etc.) instead
of the ACPI video.ko driver.
+ acpi_force_32bit_fadt_addr
+ force FADT to use 32 bit addresses rather than the
+ 64 bit X_* addresses. Some firmware have broken 64
+ bit addresses for force ACPI ignore these and use
+ the older legacy 32 bit addresses.
+
acpica_no_return_repair [HW, ACPI]
Disable AML predefined validation mechanism
This mechanism can repair the evaluation result to make
@@ -608,6 +614,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
cut the overhead, others just disable the usage. So
only cgroup_disable=memory is actually worthy}
+ cgroup_no_v1= [KNL] Disable one, multiple, all cgroup controllers in v1
+ Format: { controller[,controller...] | "all" }
+ Like cgroup_disable, but only applies to cgroup v1;
+ the blacklisted controllers remain available in cgroup2.
+
cgroup.memory= [KNL] Pass options to the cgroup memory controller.
Format: <string>
nosocket -- Disable socket memory accounting.
@@ -666,7 +677,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
clearcpuid=BITNUM [X86]
Disable CPUID feature X for the kernel. See
- arch/x86/include/asm/cpufeature.h for the valid bit
+ arch/x86/include/asm/cpufeatures.h for the valid bit
numbers. Note the Linux specific bits are not necessarily
stable over kernel options, but the vendor specific
ones should be.
@@ -976,6 +987,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
See Documentation/x86/intel_mpx.txt for more
information about the feature.
+ nopku [X86] Disable Memory Protection Keys CPU feature found
+ in some Intel CPUs.
+
eagerfpu= [X86]
on enable eager fpu restore
off disable eager fpu restore
@@ -1058,6 +1072,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
A valid base address must be provided, and the serial
port must already be setup and configured.
+ armada3700_uart,<addr>
+ Start an early, polled-mode console on the
+ Armada 3700 serial port at the specified
+ address. The serial port must already be setup
+ and configured. Options are not yet supported.
+
earlyprintk= [X86,SH,BLACKFIN,ARM,M68k]
earlyprintk=vga
earlyprintk=efi
@@ -1687,6 +1707,15 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
ip= [IP_PNP]
See Documentation/filesystems/nfs/nfsroot.txt.
+ irqaffinity= [SMP] Set the default irq affinity mask
+ Format:
+ <cpu number>,...,<cpu number>
+ or
+ <cpu number>-<cpu number>
+ (must be a positive range in ascending order)
+ or a mixture
+ <cpu number>,...,<cpu number>-<cpu number>
+
irqfixup [HW]
When an interrupt is not handled search all handlers
for it. Intended to get systems with badly broken
@@ -1750,7 +1779,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
keepinitrd [HW,ARM]
- kernelcore=nn[KMG] [KNL,X86,IA-64,PPC] This parameter
+ kernelcore= [KNL,X86,IA-64,PPC]
+ Format: nn[KMGTPE] | "mirror"
+ This parameter
specifies the amount of memory usable by the kernel
for non-movable allocations. The requested amount is
spread evenly throughout all nodes in the system. The
@@ -1766,6 +1797,14 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
use the HighMem zone if it exists, and the Normal
zone if it does not.
+ Instead of specifying the amount of memory (nn[KMGTPE]),
+ you can specify "mirror" option. In case "mirror"
+ option is specified, mirrored (reliable) memory is used
+ for non-movable allocations and remaining memory is used
+ for Movable pages. nn[KMGTPE] and "mirror" are exclusive,
+ so you can NOT specify nn[KMGTPE] and "mirror" at the same
+ time.
+
kgdbdbgp= [KGDB,HW] kgdb over EHCI usb debug port.
Format: <Controller#>[,poll interval]
The controller # is the number of the ehci usb debug
@@ -2566,6 +2605,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
nointroute [IA-64]
+ noinvpcid [X86] Disable the INVPCID cpu feature.
+
nojitter [IA-64] Disables jitter checking for ITC timers.
no-kvmclock [X86,KVM] Disable paravirtualized KVM clock driver
@@ -2582,7 +2623,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
nolapic_timer [X86-32,APIC] Do not use the local APIC timer.
noltlbs [PPC] Do not use large page/tlb entries for kernel
- lowmem mapping on PPC40x.
+ lowmem mapping on PPC40x and PPC8xx
nomca [IA-64] Disable machine check abort handling
@@ -2721,6 +2762,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
we can turn it on.
on: enable the feature
+ page_poison= [KNL] Boot-time parameter changing the state of
+ poisoning on the buddy allocator.
+ off: turn off poisoning
+ on: turn on poisoning
+
panic= [KNL] Kernel behaviour on panic: delay <timeout>
timeout > 0: seconds before rebooting
timeout = 0: wait forever
@@ -3491,6 +3537,16 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
ro [KNL] Mount root device read-only on boot
+ rodata= [KNL]
+ on Mark read-only kernel memory as read-only (default).
+ off Leave read-only kernel memory writable for debugging.
+
+ rockchip.usb_uart
+ Enable the uart passthrough on the designated usb port
+ on Rockchip SoCs. When active, the signals of the
+ debug-uart get routed to the D+ and D- pins of the usb
+ port and the regular usb controller gets disabled.
+
root= [KNL] Root filesystem
See name_to_dev_t comment in init/do_mounts.c.
@@ -3528,6 +3584,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
sched_debug [KNL] Enables verbose scheduler debug messages.
+ schedstats= [KNL,X86] Enable or disable scheduled statistics.
+ Allowed values are enable and disable. This feature
+ incurs a small amount of overhead in the scheduler
+ but is useful for debugging and performance tuning.
+
skew_tick= [KNL] Offset the periodic timer tick per cpu to mitigate
xtime_lock contention on larger systems, and/or RCU lock
contention on all systems with CONFIG_MAXSMP set.
@@ -4235,6 +4296,17 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
The default value of this parameter is determined by
the config option CONFIG_WQ_POWER_EFFICIENT_DEFAULT.
+ workqueue.debug_force_rr_cpu
+ Workqueue used to implicitly guarantee that work
+ items queued without explicit CPU specified are put
+ on the local CPU. This guarantee is no longer true
+ and while local CPU is still preferred work items
+ may be put on foreign CPUs. This debug option
+ forces round-robin CPU selection to flush out
+ usages which depend on the now broken guarantee.
+ When enabled, memory and cache locality will be
+ impacted.
+
x2apic_phys [X86-64,APIC] Use x2apic physical mode instead of
default x2apic cluster mode on platforms
supporting x2apic.