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-rw-r--r--Documentation/kernel-parameters.txt98
1 files changed, 91 insertions, 7 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 0b3de80ec8f6..82b42c958d1c 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -131,6 +131,7 @@ parameter is applicable:
More X86-64 boot options can be found in
Documentation/x86/x86_64/boot-options.txt .
X86 Either 32-bit or 64-bit x86 (same as X86-32+X86-64)
+ X86_UV SGI UV support is enabled.
XEN Xen support is enabled
In addition, the following text indicates that the option:
@@ -167,16 +168,18 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
acpi= [HW,ACPI,X86,ARM64]
Advanced Configuration and Power Interface
- Format: { force | off | strict | noirq | rsdt |
+ Format: { force | on | off | strict | noirq | rsdt |
copy_dsdt }
force -- enable ACPI if default was off
+ on -- enable ACPI but allow fallback to DT [arm64]
off -- disable ACPI if default was on
noirq -- do not use ACPI for IRQ routing
strict -- Be less tolerant of platforms that are not
strictly ACPI specification compliant.
rsdt -- prefer RSDT over (default) XSDT
copy_dsdt -- copy DSDT to memory
- For ARM64, ONLY "acpi=off" or "acpi=force" are available
+ For ARM64, ONLY "acpi=off", "acpi=on" or "acpi=force"
+ are available
See also Documentation/power/runtime_pm.txt, pci=noacpi
@@ -312,6 +315,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
acpi_osi=!* # remove all strings
acpi_osi=! # disable all built-in OS vendor
strings
+ acpi_osi=!! # enable all built-in OS vendor
+ strings
acpi_osi= # disable all strings
'acpi_osi=!' can be used in combination with single or
@@ -542,6 +547,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
Format: <int> (must be >=0)
Default: 64
+ bau= [X86_UV] Enable the BAU on SGI UV. The default
+ behavior is to disable the BAU (i.e. bau=0).
+ Format: { "0" | "1" }
+ 0 - Disable the BAU.
+ 1 - Enable the BAU.
+ unset - Disable the BAU.
+
baycom_epp= [HW,AX25]
Format: <io>,<mode>
@@ -826,6 +838,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
It will be ignored when crashkernel=X,high is not used
or memory reserved is below 4G.
+ cryptomgr.notests
+ [KNL] Disable crypto self-tests
+
cs89x0_dma= [HW,NET]
Format: <dma>
@@ -1039,6 +1054,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
the driver will use only 32-bit accessors to read/write
the device registers.
+ meson,<addr>
+ Start an early, polled-mode console on a meson serial
+ port at the specified address. The serial port must
+ already be setup and configured. Options are not yet
+ supported.
+
msm_serial,<addr>
Start an early, polled-mode console on an msm serial
port at the specified address. The serial port
@@ -1661,6 +1682,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
hwp_only
Only load intel_pstate on systems which support
hardware P state control (HWP) if available.
+ support_acpi_ppc
+ Enforce ACPI _PPC performance limits. If the Fixed ACPI
+ Description Table, specifies preferred power management
+ profile as "Enterprise Server" or "Performance Server",
+ then this feature is turned on by default.
intremap= [X86-64, Intel-IOMMU]
on enable Interrupt Remapping (default)
@@ -1767,6 +1793,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
PCI device 00:14.0 write the parameter as:
ivrs_hpet[0]=00:14.0
+ ivrs_acpihid [HW,X86_64]
+ Provide an override to the ACPI-HID:UID<->DEVICE-ID
+ mapping provided in the IVRS ACPI table. For
+ example, to map UART-HID:UID AMD0020:0 to
+ PCI device 00:14.5 write the parameter as:
+ ivrs_acpihid[00:14.5]=AMD0020:0
+
js= [HW,JOY] Analog joystick
See Documentation/input/joystick.txt.
@@ -2141,6 +2174,14 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
[KNL,SH] Allow user to override the default size for
per-device physically contiguous DMA buffers.
+ memhp_default_state=online/offline
+ [KNL] Set the initial state for the memory hotplug
+ onlining policy. If not specified, the default value is
+ set according to the
+ CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE kernel config
+ option.
+ See Documentation/memory-hotplug.txt.
+
memmap=exactmap [KNL,X86] Enable setting of an exact
E820 memory map, as specified by the user.
Such memmap=exactmap lines can be constructed based on
@@ -2538,6 +2579,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
nohugeiomap [KNL,x86] Disable kernel huge I/O mappings.
+ nosmt [KNL,S390] Disable symmetric multithreading (SMT).
+ Equivalent to smt=1.
+
noxsave [BUGS=X86] Disables x86 extended register state save
and restore using xsave. The kernel will fallback to
enabling legacy floating-point and sse state.
@@ -2921,11 +2965,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
for broken drivers that don't call it.
skip_isa_align [X86] do not align io start addr, so can
handle more pci cards
- firmware [ARM] Do not re-enumerate the bus but instead
- just use the configuration from the
- bootloader. This is currently used on
- IXP2000 systems where the bus has to be
- configured a certain way for adjunct CPUs.
noearly [X86] Don't do any early type 1 scanning.
This might help on some broken boards which
machine check when some devices' config space
@@ -3284,6 +3323,44 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
Lazy RCU callbacks are those which RCU can
prove do nothing more than free memory.
+ rcuperf.gp_exp= [KNL]
+ Measure performance of expedited synchronous
+ grace-period primitives.
+
+ rcuperf.holdoff= [KNL]
+ Set test-start holdoff period. The purpose of
+ this parameter is to delay the start of the
+ test until boot completes in order to avoid
+ interference.
+
+ rcuperf.nreaders= [KNL]
+ Set number of RCU readers. The value -1 selects
+ N, where N is the number of CPUs. A value
+ "n" less than -1 selects N-n+1, where N is again
+ the number of CPUs. For example, -2 selects N
+ (the number of CPUs), -3 selects N+1, and so on.
+ A value of "n" less than or equal to -N selects
+ a single reader.
+
+ rcuperf.nwriters= [KNL]
+ Set number of RCU writers. The values operate
+ the same as for rcuperf.nreaders.
+ N, where N is the number of CPUs
+
+ rcuperf.perf_runnable= [BOOT]
+ Start rcuperf running at boot time.
+
+ rcuperf.shutdown= [KNL]
+ Shut the system down after performance tests
+ complete. This is useful for hands-off automated
+ testing.
+
+ rcuperf.perf_type= [KNL]
+ Specify the RCU implementation to test.
+
+ rcuperf.verbose= [KNL]
+ Enable additional printk() statements.
+
rcutorture.cbflood_inter_holdoff= [KNL]
Set holdoff time (jiffies) between successive
callback-flood tests.
@@ -3695,6 +3772,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
1: Fast pin select (default)
2: ATC IRMode
+ smt [KNL,S390] Set the maximum number of threads (logical
+ CPUs) to use per physical CPU on systems capable of
+ symmetric multithreading (SMT). Will be capped to the
+ actual hardware limit.
+ Format: <integer>
+ Default: -1 (no limit)
+
softlockup_panic=
[KNL] Should the soft-lockup detector generate panics.
Format: <integer>