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-rw-r--r--Documentation/kernel-parameters.txt138
1 files changed, 106 insertions, 32 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 7116fda7077f..b9f67781c577 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -214,6 +214,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
unusable. The "log_buf_len" parameter may be useful
if you need to capture more output.
+ acpi_force_table_verification [HW,ACPI]
+ Enable table checksum verification during early stage.
+ By default, this is disabled due to x86 early mapping
+ size limitation.
+
acpi_irq_balance [HW,ACPI]
ACPI will balance active IRQs
default in APIC mode
@@ -229,7 +234,31 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
use by PCI
Format: <irq>,<irq>...
- acpi_no_auto_ssdt [HW,ACPI] Disable automatic loading of SSDT
+ acpi_no_auto_serialize [HW,ACPI]
+ Disable auto-serialization of AML methods
+ AML control methods that contain the opcodes to create
+ named objects will be marked as "Serialized" by the
+ auto-serialization feature.
+ This feature is enabled by default.
+ This option allows to turn off the feature.
+
+ acpi_no_static_ssdt [HW,ACPI]
+ Disable installation of static SSDTs at early boot time
+ By default, SSDTs contained in the RSDT/XSDT will be
+ installed automatically and they will appear under
+ /sys/firmware/acpi/tables.
+ This option turns off this feature.
+ Note that specifying this option does not affect
+ dynamic table installation which will install SSDT
+ tables to /sys/firmware/acpi/tables/dynamic.
+
+ acpica_no_return_repair [HW, ACPI]
+ Disable AML predefined validation mechanism
+ This mechanism can repair the evaluation result to make
+ the return objects more ACPI specification compliant.
+ This option is useful for developers to identify the
+ root cause of an AML interpreter issue when the issue
+ has something to do with the repair mechanism.
acpi_os_name= [HW,ACPI] Tell ACPI BIOS the name of the OS
Format: To spoof as Windows 98: ="Microsoft Windows"
@@ -298,8 +327,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
Format: { level | edge | high | low }
- acpi_serialize [HW,ACPI] force serialization of AML methods
-
acpi_skip_timer_override [HW,ACPI]
Recognize and ignore IRQ0/pin2 Interrupt Override.
For broken nForce2 BIOS resulting in XT-PIC timer.
@@ -603,8 +630,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
Also note the kernel might malfunction if you disable
some critical bits.
- cma=nn[MG] [ARM,KNL]
- Sets the size of kernel global memory area for contiguous
+ cma=nn[MG]@[start[MG][-end[MG]]]
+ [ARM,X86,KNL]
+ Sets the size of kernel global memory area for
+ contiguous memory allocations and optionally the
+ placement constraint by the physical address range of
memory allocations. For more information, see
include/linux/dma-contiguous.h
@@ -790,13 +820,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
dhash_entries= [KNL]
Set number of hash buckets for dentry cache.
- digi= [HW,SERIAL]
- IO parameters + enable/disable command.
-
- digiepca= [HW,SERIAL]
- See drivers/char/README.epca and
- Documentation/serial/digiepca.txt.
-
disable= [IPV6]
See Documentation/networking/ipv6.txt.
@@ -870,7 +893,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
Enable debug messages at boot time. See
Documentation/dynamic-debug-howto.txt for details.
+ early_ioremap_debug [KNL]
+ Enable debug messages in early_ioremap support. This
+ is useful for tracking down temporary early mappings
+ which are not unmapped.
+
earlycon= [KNL] Output early console device and options.
+
uart[8250],io,<addr>[,options]
uart[8250],mmio,<addr>[,options]
uart[8250],mmio32,<addr>[,options]
@@ -880,7 +909,15 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
(mmio) or 32-bit (mmio32).
The options are the same as for ttyS, above.
- earlyprintk= [X86,SH,BLACKFIN,ARM]
+ pl011,<addr>
+ Start an early, polled-mode console on a pl011 serial
+ port at the specified address. The pl011 serial port
+ must already be setup and configured. Options are not
+ yet supported.
+
+ smh Use ARM semihosting calls for early console.
+
+ earlyprintk= [X86,SH,BLACKFIN,ARM,M68k]
earlyprintk=vga
earlyprintk=efi
earlyprintk=xen
@@ -1011,6 +1048,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
parameter will force ia64_sal_cache_flush to call
ia64_pal_cache_flush instead of SAL_CACHE_FLUSH.
+ forcepae [X86-32]
+ Forcefully enable Physical Address Extension (PAE).
+ Many Pentium M systems disable PAE but may have a
+ functionally usable PAE implementation.
+ Warning: use of this parameter will taint the kernel
+ and may cause unknown problems.
+
ftrace=[tracer]
[FTRACE] will set and start the specified tracer
as early as possible in order to facilitate early
@@ -1268,6 +1312,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
for working out where the kernel is dying during
startup.
+ initcall_blacklist= [KNL] Do not execute a comma-separated list of
+ initcall functions. Useful for debugging built-in
+ modules and initcalls.
+
initrd= [BOOT] Specify the location of the initial ramdisk
inport.irq= [HW] Inport (ATI XL and Microsoft) busmouse driver
@@ -2053,8 +2101,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
IOAPICs that may be present in the system.
nokaslr [X86]
- Disable kernel base offset ASLR (Address Space
- Layout Randomization) if built into the kernel.
+ Disable kernel and module base offset ASLR (Address
+ Space Layout Randomization) if built into the kernel.
noautogroup Disable scheduler automatic task group creation.
@@ -2199,10 +2247,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
noreplace-smp [X86-32,SMP] Don't replace SMP instructions
with UP alternatives
- nordrand [X86] Disable the direct use of the RDRAND
- instruction even if it is supported by the
- processor. RDRAND is still available to user
- space applications.
+ nordrand [X86] Disable kernel use of the RDRAND and
+ RDSEED instructions even if they are supported
+ by the processor. RDRAND and RDSEED are still
+ available to user space applications.
noresume [SWSUSP] Disables resume and restores original swap
space.
@@ -2313,6 +2361,14 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
timeout < 0: reboot immediately
Format: <timeout>
+ crash_kexec_post_notifiers
+ Run kdump after running panic-notifiers and dumping
+ kmsg. This only for the users who doubt kdump always
+ succeeds in any situation.
+ Note that this also increases risks of kdump failure,
+ because some panic notifiers can make the crashed
+ kernel more unstable.
+
parkbd.port= [HW] Parallel port number the keyboard adapter is
connected to, default is 0.
Format: <parport#>
@@ -2537,6 +2593,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
pcmv= [HW,PCMCIA] BadgePAD 4
+ pd_ignore_unused
+ [PM]
+ Keep all power-domains already enabled by bootloader on,
+ even if no driver has claimed them. This is useful
+ for debug and development, but should not be
+ needed on a platform with proper driver support.
+
pd. [PARIDE]
See Documentation/blockdev/paride.txt.
@@ -2863,6 +2926,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
[KNL, SMP] Set scheduler's default relax_domain_level.
See Documentation/cgroups/cpusets.txt.
+ relative_sleep_states=
+ [SUSPEND] Use sleep state labeling where the deepest
+ state available other than hibernation is always "mem".
+ Format: { "0" | "1" }
+ 0 -- Traditional sleep state labels.
+ 1 -- Relative sleep state labels.
+
reserve= [KNL,BUGS] Force the kernel to ignore some iomem area
reservetop= [X86-32]
@@ -2906,9 +2976,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
rhash_entries= [KNL,NET]
Set number of hash buckets for route cache
- riscom8= [HW,SERIAL]
- Format: <io_board1>[,<io_board2>[,...<io_boardN>]]
-
ro [KNL] Mount root device read-only on boot
root= [KNL] Root filesystem
@@ -3050,9 +3117,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
sonypi.*= [HW] Sony Programmable I/O Control Device driver
See Documentation/laptops/sonypi.txt
- specialix= [HW,SERIAL] Specialix multi-serial port adapter
- See Documentation/serial/specialix.txt.
-
spia_io_base= [HW,MTD]
spia_fio_base=
spia_pedr=
@@ -3409,14 +3473,24 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
of CONFIG_HIGHPTE.
vdso= [X86,SH]
- vdso=2: enable compat VDSO (default with COMPAT_VDSO)
- vdso=1: enable VDSO (default)
+ On X86_32, this is an alias for vdso32=. Otherwise:
+
+ vdso=1: enable VDSO (the default)
vdso=0: disable VDSO mapping
- vdso32= [X86]
- vdso32=2: enable compat VDSO (default with COMPAT_VDSO)
- vdso32=1: enable 32-bit VDSO (default)
- vdso32=0: disable 32-bit VDSO mapping
+ vdso32= [X86] Control the 32-bit vDSO
+ vdso32=1: enable 32-bit VDSO
+ vdso32=0 or vdso32=2: disable 32-bit VDSO
+
+ See the help text for CONFIG_COMPAT_VDSO for more
+ details. If CONFIG_COMPAT_VDSO is set, the default is
+ vdso32=0; otherwise, the default is vdso32=1.
+
+ For compatibility with older kernels, vdso32=2 is an
+ alias for vdso32=0.
+
+ Try vdso32=0 if you encounter an error that says:
+ dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
vector= [IA-64,SMP]
vector=percpu: enable percpu vector domain
@@ -3431,7 +3505,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
the allocated input device; If set to 0, video driver
will only send out the event without touching backlight
brightness level.
- default: 1
+ default: 0
virtio_mmio.device=
[VMMIO] Memory mapped virtio (platform) device.