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-rw-r--r--Documentation/kernel-parameters.txt110
1 files changed, 75 insertions, 35 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 6726139bd289..c84d078a6376 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -179,11 +179,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
See also Documentation/power/runtime_pm.txt, pci=noacpi
- acpi_rsdp= [ACPI,EFI,KEXEC]
- Pass the RSDP address to the kernel, mostly used
- on machines running EFI runtime service to boot the
- second kernel for kdump.
-
acpi_apic_instance= [ACPI, IOAPIC]
Format: <int>
2: use 2nd APIC table, if available
@@ -197,6 +192,14 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
(e.g. thinkpad_acpi, sony_acpi, etc.) instead
of the ACPI video.ko driver.
+ 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.debug_layer= [HW,ACPI,ACPI_DEBUG]
acpi.debug_level= [HW,ACPI,ACPI_DEBUG]
Format: <int>
@@ -225,6 +228,22 @@ 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_enforce_resources= [ACPI]
+ { strict | lax | no }
+ Check for resource conflicts between native drivers
+ and ACPI OperationRegions (SystemIO and SystemMemory
+ only). IO ports and memory declared in ACPI might be
+ used by the ACPI subsystem in arbitrary AML code and
+ can interfere with legacy drivers.
+ strict (default): access to resources claimed by ACPI
+ is denied; legacy drivers trying to access reserved
+ resources will fail to bind to device using them.
+ lax: access to resources claimed by ACPI is allowed;
+ legacy drivers trying to access reserved resources
+ will bind successfully but a warning message is logged.
+ no: ACPI OperationRegions are not marked as reserved,
+ no further checks are performed.
+
acpi_force_table_verification [HW,ACPI]
Enable table checksum verification during early stage.
By default, this is disabled due to x86 early mapping
@@ -253,6 +272,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
This feature is enabled by default.
This option allows to turn off the feature.
+ acpi_no_memhotplug [ACPI] Disable memory hotplug. Useful for kdump
+ kernels.
+
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
@@ -263,13 +285,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
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_rsdp= [ACPI,EFI,KEXEC]
+ Pass the RSDP address to the kernel, mostly used
+ on machines running EFI runtime service to boot the
+ second kernel for kdump.
acpi_os_name= [HW,ACPI] Tell ACPI BIOS the name of the OS
Format: To spoof as Windows 98: ="Microsoft Windows"
@@ -365,25 +384,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
Use timer override. For some broken Nvidia NF5 boards
that require a timer override, but don't have HPET
- acpi_enforce_resources= [ACPI]
- { strict | lax | no }
- Check for resource conflicts between native drivers
- and ACPI OperationRegions (SystemIO and SystemMemory
- only). IO ports and memory declared in ACPI might be
- used by the ACPI subsystem in arbitrary AML code and
- can interfere with legacy drivers.
- strict (default): access to resources claimed by ACPI
- is denied; legacy drivers trying to access reserved
- resources will fail to bind to device using them.
- lax: access to resources claimed by ACPI is allowed;
- legacy drivers trying to access reserved resources
- will bind successfully but a warning message is logged.
- 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.
@@ -746,6 +746,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
cpuidle.off=1 [CPU_IDLE]
disable the cpuidle sub-system
+ cpu_init_udelay=N
+ [X86] Delay for N microsec between assert and de-assert
+ of APIC INIT to start processors. This delay occurs
+ on every CPU online, such as boot, and resume from suspend.
+ Default: 10000
+
cpcihp_generic= [HW,PCI] Generic port I/O CompactPCI driver
Format:
<first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>]
@@ -937,6 +943,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
Enable debug messages at boot time. See
Documentation/dynamic-debug-howto.txt for details.
+ nompx [X86] Disables Intel Memory Protection Extensions.
+ See Documentation/x86/intel_mpx.txt for more
+ information about the feature.
+
eagerfpu= [X86]
on enable eager fpu restore
off disable eager fpu restore
@@ -1009,6 +1019,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
earlyprintk=serial[,0x...[,baudrate]]
earlyprintk=ttySn[,baudrate]
earlyprintk=dbgp[debugController#]
+ earlyprintk=pciserial,bus:device.function[,baudrate]
earlyprintk is useful when the kernel crashes before
the normal console is initialized. It is not enabled by
@@ -1780,6 +1791,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
* [no]ncq: Turn on or off NCQ.
+ * [no]ncqtrim: Turn off queued DSM TRIM.
+
* nohrst, nosrst, norst: suppress hard, soft
and both resets.
@@ -2443,7 +2456,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
nomca [IA-64] Disable machine check abort handling
- nomce [X86-32] Machine Check Exception
+ nomce [X86-32] Disable Machine Check Exception
nomfgpt [X86-32] Disable Multi-Function General Purpose
Timer usage (for AMD Geode machines).
@@ -2998,11 +3011,34 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
Set maximum number of finished RCU callbacks to
process in one batch.
+ rcutree.dump_tree= [KNL]
+ Dump the structure of the rcu_node combining tree
+ out at early boot. This is used for diagnostic
+ purposes, to verify correct tree setup.
+
+ rcutree.gp_cleanup_delay= [KNL]
+ Set the number of jiffies to delay each step of
+ RCU grace-period cleanup. This only has effect
+ when CONFIG_RCU_TORTURE_TEST_SLOW_CLEANUP is set.
+
rcutree.gp_init_delay= [KNL]
Set the number of jiffies to delay each step of
RCU grace-period initialization. This only has
- effect when CONFIG_RCU_TORTURE_TEST_SLOW_INIT is
- set.
+ effect when CONFIG_RCU_TORTURE_TEST_SLOW_INIT
+ is set.
+
+ rcutree.gp_preinit_delay= [KNL]
+ Set the number of jiffies to delay each step of
+ RCU grace-period pre-initialization, that is,
+ the propagation of recent CPU-hotplug changes up
+ the rcu_node combining tree. This only has effect
+ when CONFIG_RCU_TORTURE_TEST_SLOW_PREINIT is set.
+
+ rcutree.rcu_fanout_exact= [KNL]
+ Disable autobalancing of the rcu_node combining
+ tree. This is used by rcutorture, and might
+ possibly be useful for architectures having high
+ cache-to-cache transfer latencies.
rcutree.rcu_fanout_leaf= [KNL]
Increase the number of CPUs assigned to each
@@ -3107,7 +3143,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
test, hence the "fake".
rcutorture.nreaders= [KNL]
- Set number of RCU readers.
+ Set number of RCU readers. The value -1 selects
+ N-1, where N is the number of CPUs. A value
+ "n" less than -1 selects N-n-2, where N is again
+ the number of CPUs. For example, -2 selects N
+ (the number of CPUs), -3 selects N+1, and so on.
rcutorture.object_debug= [KNL]
Enable debug-object double-call_rcu() testing.