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-rw-r--r--Documentation/kernel-parameters.txt78
1 files changed, 67 insertions, 11 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 363e348bff9..1da94654877 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -594,6 +594,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
is selected automatically. Check
Documentation/kdump/kdump.txt for further details.
+ crashkernel_low=size[KMG]
+ [KNL, x86] parts under 4G.
+
crashkernel=range1:size1[,range2:size2,...][@offset]
[KNL] Same as above, but depends on the memory
in the running system. The syntax of range is
@@ -1039,16 +1042,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
Claim all unknown PCI IDE storage controllers.
idle= [X86]
- Format: idle=poll, idle=mwait, idle=halt, idle=nomwait
+ Format: idle=poll, idle=halt, idle=nomwait
Poll forces a polling idle loop that can slightly
improve the performance of waking up a idle CPU, but
will use a lot of power and make the system run hot.
Not recommended.
- idle=mwait: On systems which support MONITOR/MWAIT but
- the kernel chose to not use it because it doesn't save
- as much power as a normal idle loop, use the
- MONITOR/MWAIT idle loop anyways. Performance should be
- the same as idle=poll.
idle=halt: Halt is forced to be used for CPU idle.
In such case C2/C3 won't be used again.
idle=nomwait: Disable mwait for CPU C-states
@@ -1131,6 +1129,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
0 disables intel_idle and fall back on acpi_idle.
1 to 6 specify maximum depth of C-state.
+ intel_pstate= [X86]
+ disable
+ Do not enable intel_pstate as the default
+ scaling driver for the supported processors
+
intremap= [X86-64, Intel-IOMMU]
on enable Interrupt Remapping (default)
off disable Interrupt Remapping
@@ -1637,6 +1640,42 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
that the amount of memory usable for all allocations
is not too small.
+ movablemem_map=acpi
+ [KNL,X86,IA-64,PPC] This parameter is similar to
+ memmap except it specifies the memory map of
+ ZONE_MOVABLE.
+ This option inform the kernel to use Hot Pluggable bit
+ in flags from SRAT from ACPI BIOS to determine which
+ memory devices could be hotplugged. The corresponding
+ memory ranges will be set as ZONE_MOVABLE.
+ NOTE: Whatever node the kernel resides in will always
+ be un-hotpluggable.
+
+ movablemem_map=nn[KMG]@ss[KMG]
+ [KNL,X86,IA-64,PPC] This parameter is similar to
+ memmap except it specifies the memory map of
+ ZONE_MOVABLE.
+ If user specifies memory ranges, the info in SRAT will
+ be ingored. And it works like the following:
+ - If more ranges are all within one node, then from
+ lowest ss to the end of the node will be ZONE_MOVABLE.
+ - If a range is within a node, then from ss to the end
+ of the node will be ZONE_MOVABLE.
+ - If a range covers two or more nodes, then from ss to
+ the end of the 1st node will be ZONE_MOVABLE, and all
+ the rest nodes will only have ZONE_MOVABLE.
+ If memmap is specified at the same time, the
+ movablemem_map will be limited within the memmap
+ areas. If kernelcore or movablecore is also specified,
+ movablemem_map will have higher priority to be
+ satisfied. So the administrator should be careful that
+ the amount of movablemem_map areas are not too large.
+ Otherwise kernel won't have enough memory to start.
+ NOTE: We don't stop users specifying the node the
+ kernel resides in as hotpluggable so that this
+ option can be used as a workaround of firmware
+ bugs.
+
MTD_Partition= [MTD]
Format: <name>,<region-number>,<size>,<offset>
@@ -1886,10 +1925,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
wfi(ARM) instruction doesn't work correctly and not to
use it. This is also useful when using JTAG debugger.
- no-hlt [BUGS=X86-32] Tells the kernel that the hlt
- instruction doesn't work correctly and not to
- use it.
-
no_file_caps Tells the kernel not to honor file capabilities. The
only way then for a file to be executed with privilege
is to be setuid root or executed by root.
@@ -2227,6 +2262,21 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
This sorting is done to get a device
order compatible with older (<= 2.4) kernels.
nobfsort Don't sort PCI devices into breadth-first order.
+ pcie_bus_tune_off Disable PCIe MPS (Max Payload Size)
+ tuning and use the BIOS-configured MPS defaults.
+ pcie_bus_safe Set every device's MPS to the largest value
+ supported by all devices below the root complex.
+ pcie_bus_perf Set device MPS to the largest allowable MPS
+ based on its parent bus. Also set MRRS (Max
+ Read Request Size) to the largest supported
+ value (no larger than the MPS that the device
+ or bus can support) for best performance.
+ pcie_bus_peer2peer Set every device's MPS to 128B, which
+ every device is guaranteed to support. This
+ configuration allows peer-to-peer DMA between
+ any pair of devices, possibly at the cost of
+ reduced performance. This also guarantees
+ that hot-added devices will work.
cbiosize=nn[KMG] The fixed amount of bus space which is
reserved for the CardBus bridge's IO window.
The default value is 256 bytes.
@@ -2248,6 +2298,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
the default.
off: Turn ECRC off
on: Turn ECRC on.
+ hpiosize=nn[KMG] The fixed amount of bus space which is
+ reserved for hotplug bridge's IO window.
+ Default size is 256 bytes.
+ hpmemsize=nn[KMG] The fixed amount of bus space which is
+ reserved for hotplug bridge's memory window.
+ Default size is 2 megabytes.
realloc= Enable/disable reallocating PCI bridge resources
if allocations done by BIOS are too small to
accommodate resources required by all child
@@ -2438,7 +2494,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
real-time workloads. It can also improve energy
efficiency for asymmetric multiprocessors.
- rcu_nocbs_poll [KNL,BOOT]
+ rcu_nocb_poll [KNL,BOOT]
Rather than requiring that offloaded CPUs
(specified by rcu_nocbs= above) explicitly
awaken the corresponding "rcuoN" kthreads,