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authorScott Wood <scottwood@freescale.com>2013-11-01 21:17:16 (GMT)
committerScott Wood <scottwood@freescale.com>2013-11-03 22:47:10 (GMT)
commit31110de40dca4d4aeff4f253b3def948b88fa590 (patch)
tree0d811783836d52f15e37b4244de54f44ed4f93ad /Documentation/kernel-parameters.txt
parentae60d5d27c429b13cf28a09ab8b9d30682433c5a (diff)
parent8bb495e3f02401ee6f76d1b1d77f3ac9f079e376 (diff)
downloadlinux-fsl-qoriq-31110de40dca4d4aeff4f253b3def948b88fa590.tar.xz
Merge tag 'v3.10' into sdk-kernel-3.10
git rebase --continue Linux 3.10 Conflicts: Documentation/virtual/kvm/api.txt arch/ia64/kvm/Makefile arch/powerpc/Kconfig arch/powerpc/Makefile arch/powerpc/boot/dts/b4420qds.dts arch/powerpc/boot/dts/b4860qds.dts arch/powerpc/boot/dts/b4qds.dts arch/powerpc/boot/dts/fsl/b4420si-post.dtsi arch/powerpc/boot/dts/fsl/b4420si-pre.dtsi arch/powerpc/boot/dts/fsl/b4860si-post.dtsi arch/powerpc/boot/dts/fsl/b4860si-pre.dtsi arch/powerpc/boot/dts/fsl/b4si-post.dtsi arch/powerpc/boot/dts/fsl/p1010si-post.dtsi arch/powerpc/boot/dts/fsl/p2041si-post.dtsi arch/powerpc/boot/dts/fsl/p3041si-post.dtsi arch/powerpc/boot/dts/fsl/p4080si-post.dtsi arch/powerpc/boot/dts/fsl/p5020si-post.dtsi arch/powerpc/boot/dts/fsl/p5040si-post.dtsi arch/powerpc/boot/dts/fsl/qonverge-usb2-dr-0.dtsi arch/powerpc/boot/dts/fsl/qoriq-sec5.0-0.dtsi arch/powerpc/boot/dts/fsl/t4240si-post.dtsi arch/powerpc/boot/dts/fsl/t4240si-pre.dtsi arch/powerpc/boot/dts/p1025rdb_36b.dts arch/powerpc/boot/dts/t4240qds.dts arch/powerpc/configs/corenet64_smp_defconfig arch/powerpc/configs/mpc85xx_defconfig arch/powerpc/configs/mpc85xx_smp_defconfig arch/powerpc/include/asm/cputable.h arch/powerpc/include/asm/kvm_host.h arch/powerpc/include/asm/kvm_ppc.h arch/powerpc/include/asm/machdep.h arch/powerpc/include/uapi/asm/kvm.h arch/powerpc/kernel/cpu_setup_fsl_booke.S arch/powerpc/kernel/cputable.c arch/powerpc/kernel/idle.c arch/powerpc/kernel/pci-common.c arch/powerpc/kvm/Kconfig arch/powerpc/kvm/book3s.c arch/powerpc/kvm/booke.c arch/powerpc/kvm/e500.c arch/powerpc/kvm/e500_mmu.c arch/powerpc/kvm/e500_mmu_host.c arch/powerpc/kvm/e500mc.c arch/powerpc/kvm/emulate.c arch/powerpc/kvm/irq.h arch/powerpc/kvm/mpic.c arch/powerpc/kvm/powerpc.c arch/powerpc/mm/tlb_nohash.c arch/powerpc/platforms/85xx/Kconfig arch/powerpc/platforms/85xx/b4_qds.c arch/powerpc/platforms/85xx/t4240_qds.c arch/powerpc/platforms/pseries/smp.c arch/powerpc/sysdev/fsl_85xx_l2ctlr.c arch/powerpc/sysdev/fsl_msi.c arch/powerpc/sysdev/fsl_pci.c arch/powerpc/sysdev/fsl_pci.h arch/powerpc/sysdev/mpic.c arch/x86/kvm/Makefile arch/x86/kvm/x86.c drivers/Kconfig drivers/clk/Kconfig drivers/cpufreq/Makefile drivers/crypto/caam/caamalg.c drivers/crypto/caam/intern.h drivers/crypto/caam/jr.c drivers/crypto/caam/regs.h drivers/infiniband/ulp/ipoib/ipoib_ethtool.c drivers/iommu/Makefile drivers/iommu/amd_iommu.c drivers/iommu/exynos-iommu.c drivers/iommu/intel-iommu.c drivers/iommu/iommu.c drivers/iommu/msm_iommu.c drivers/iommu/omap-iommu.c drivers/iommu/tegra-gart.c drivers/iommu/tegra-smmu.c drivers/misc/Makefile drivers/mmc/card/block.c drivers/mmc/card/queue.c drivers/mmc/core/core.c drivers/mtd/nand/fsl_ifc_nand.c drivers/net/ethernet/3com/3c501.c drivers/net/ethernet/8390/3c503.c drivers/net/ethernet/dec/ewrk3.c drivers/net/ethernet/freescale/fec.c drivers/net/ethernet/freescale/gianfar.c drivers/net/ethernet/freescale/gianfar.h drivers/net/ethernet/i825xx/3c505.c drivers/net/ethernet/i825xx/3c507.c drivers/rtc/rtc-ds3232.c drivers/s390/net/qeth_core_main.c drivers/staging/Kconfig drivers/staging/Makefile drivers/staging/ccg/u_ether.c drivers/usb/gadget/fsl_udc_core.c drivers/usb/otg/fsl_otg.c drivers/vfio/vfio.c drivers/watchdog/Kconfig include/linux/iommu.h include/linux/kvm_host.h include/linux/mmc/sdhci.h include/linux/msi.h include/linux/netdev_features.h include/linux/pci.h include/linux/skbuff.h include/net/ip6_route.h include/net/sch_generic.h include/net/xfrm.h include/uapi/linux/kvm.h net/core/netpoll.c virt/kvm/irqchip.c virt/kvm/kvm_main.c
Diffstat (limited to 'Documentation/kernel-parameters.txt')
-rw-r--r--Documentation/kernel-parameters.txt203
1 files changed, 174 insertions, 29 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 2f04b62..614a89c 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -44,6 +44,8 @@ parameter is applicable:
AVR32 AVR32 architecture is enabled.
AX25 Appropriate AX.25 support is enabled.
BLACKFIN Blackfin architecture is enabled.
+ CLK Common clock infrastructure is enabled.
+ CMA Contiguous Memory Area support is enabled.
DRM Direct Rendering Management support is enabled.
DYNAMIC_DEBUG Build in debug messages and enable them at runtime
EDD BIOS Enhanced Disk Drive Services (EDD) is enabled
@@ -320,6 +322,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
on: enable for both 32- and 64-bit processes
off: disable for both 32- and 64-bit processes
+ alloc_snapshot [FTRACE]
+ Allocate the ftrace snapshot buffer on boot up when the
+ main buffer is allocated. This is handy if debugging
+ and you need to use tracing_snapshot() on boot up, and
+ do not want to use tracing_snapshot_alloc() as it needs
+ to be done where GFP_KERNEL allocations are allowed.
+
amd_iommu= [HW,X86-64]
Pass parameters to the AMD IOMMU driver in the system.
Possible values are:
@@ -468,6 +477,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
cio_ignore= [S390]
See Documentation/s390/CommonIO for details.
+ clk_ignore_unused
+ [CLK]
+ Keep all clocks 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.
+ For more information, see Documentation/clk.txt.
clock= [BUGS=X86-32, HW] gettimeofday clocksource override.
[Deprecated]
@@ -567,6 +583,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
UART at the specified I/O port or MMIO address,
switching to the matching ttyS device later. The
options are the same as for ttyS, above.
+ hvc<n> Use the hypervisor console device <n>. This is for
+ both Xen and PowerPC hypervisors.
If the device connected to the port is not a TTY but a braille
device, prepend "brl," before the device type, for instance
@@ -604,6 +622,26 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
a memory unit (amount[KMG]). See also
Documentation/kdump/kdump.txt for an example.
+ crashkernel=size[KMG],high
+ [KNL, x86_64] range could be above 4G. Allow kernel
+ to allocate physical memory region from top, so could
+ be above 4G if system have more than 4G ram installed.
+ Otherwise memory region will be allocated below 4G, if
+ available.
+ It will be ignored if crashkernel=X is specified.
+ crashkernel=size[KMG],low
+ [KNL, x86_64] range under 4G. When crashkernel=X,high
+ is passed, kernel could allocate physical memory region
+ above 4G, that cause second kernel crash on system
+ that require some amount of low memory, e.g. swiotlb
+ requires at least 64M+32K low memory. Kernel would
+ try to allocate 72M below 4G automatically.
+ This one let user to specify own low range under 4G
+ for second kernel instead.
+ 0: to disable low allocation.
+ It will be ignored when crashkernel=X,high is not used
+ or memory reserved is below 4G.
+
cs89x0_dma= [HW,NET]
Format: <dma>
@@ -755,18 +793,31 @@ 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]
+ earlyprintk= [X86,SH,BLACKFIN,ARM]
earlyprintk=vga
+ earlyprintk=xen
earlyprintk=serial[,ttySn[,baudrate]]
+ earlyprintk=serial[,0x...[,baudrate]]
earlyprintk=ttySn[,baudrate]
earlyprintk=dbgp[debugController#]
+ earlyprintk is useful when the kernel crashes before
+ the normal console is initialized. It is not enabled by
+ default because it has some cosmetic problems.
+
Append ",keep" to not disable it when the real console
takes over.
Only vga or serial or usb debug port at a time.
- Currently only ttyS0 and ttyS1 are supported.
+ Currently only ttyS0 and ttyS1 may be specified by
+ name. Other I/O ports may be explicitly specified
+ on some architectures (x86 and arm at least) by
+ replacing ttySn with an I/O port address, like this:
+ earlyprintk=serial,0x1008,115200
+ You can find the port for a given device in
+ /proc/tty/driver/serial:
+ 2: uart:ST16650V2 port:00001008 irq:18 ...
Interaction with the standard serial driver is not
very good.
@@ -774,6 +825,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
The VGA output is eventually overwritten by the real
console.
+ The xen output can only be used by Xen PV guests.
+
ekgdboc= [X86,KGDB] Allow early kernel console debugging
ekgdboc=kbd
@@ -783,6 +836,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
edd= [EDD]
Format: {"off" | "on" | "skip[mbr]"}
+ efi_no_storage_paranoia [EFI; X86]
+ Using this parameter you can use more than 50% of
+ your efi variable storage. Use this parameter only if
+ you are really sure that your UEFI does sane gc and
+ fulfills the spec otherwise your board may brick.
+
eisa_irq_edge= [PARISC,HW]
See header of drivers/parisc/eisa.c.
@@ -973,6 +1032,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
If specified, z/VM IUCV HVC accepts connections
from listed z/VM user IDs only.
+ hwthread_map= [METAG] Comma-separated list of Linux cpu id to
+ hardware thread id mappings.
+ Format: <cpu>:<hwthread>
+
keep_bootcon [KNL]
Do not unregister boot console at start. This is only
useful for debugging when something happens in the window
@@ -1042,16 +1105,11 @@ 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
@@ -1134,6 +1192,11 @@ 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
@@ -1217,6 +1280,20 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
iucv= [HW,NET]
+ ivrs_ioapic [HW,X86_64]
+ Provide an override to the IOAPIC-ID<->DEVICE-ID
+ mapping provided in the IVRS ACPI table. For
+ example, to map IOAPIC-ID decimal 10 to
+ PCI device 00:14.0 write the parameter as:
+ ivrs_ioapic[10]=00:14.0
+
+ ivrs_hpet [HW,X86_64]
+ Provide an override to the HPET-ID<->DEVICE-ID
+ mapping provided in the IVRS ACPI table. For
+ example, to map HPET-ID decimal 0 to
+ PCI device 00:14.0 write the parameter as:
+ ivrs_hpet[0]=00:14.0
+
js= [HW,JOY] Analog joystick
See Documentation/input/joystick.txt.
@@ -1616,7 +1693,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
module.sig_enforce
[KNL] When CONFIG_MODULE_SIG is set, this means that
modules without (valid) signatures will fail to load.
- Note that if CONFIG_MODULE_SIG_ENFORCE is set, that
+ Note that if CONFIG_MODULE_SIG_FORCE is set, that
is always true, so this option does nothing.
mousedev.tap_time=
@@ -1889,10 +1966,6 @@ 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.
@@ -1908,6 +1981,14 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
Valid arguments: on, off
Default: on
+ nohz_full= [KNL,BOOT]
+ In kernels built with CONFIG_NO_HZ_FULL=y, set
+ the specified list of CPUs whose tick will be stopped
+ whenever possible. The boot CPU will be forced outside
+ the range to maintain the timekeeping.
+ The CPUs in this range must also be included in the
+ rcu_nocbs= set.
+
noiotrap [SH] Disables trapped I/O port accesses.
noirqdebug [X86-32] Disables the code which attempts to detect and
@@ -1969,8 +2050,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
noreplace-smp [X86-32,SMP] Don't replace SMP instructions
with UP alternatives
- noresidual [PPC] Don't use residual data on PReP machines.
-
nordrand [X86] Disable the direct use of the RDRAND
instruction even if it is supported by the
processor. RDRAND is still available to user
@@ -2230,6 +2309,21 @@ 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.
@@ -2251,6 +2345,12 @@ 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
@@ -2435,9 +2535,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
In kernels built with CONFIG_RCU_NOCB_CPU=y, set
the specified list of CPUs to be no-callback CPUs.
Invocation of these CPUs' RCU callbacks will
- be offloaded to "rcuoN" kthreads created for
- that purpose. This reduces OS jitter on the
+ be offloaded to "rcuox/N" kthreads created for
+ that purpose, where "x" is "b" for RCU-bh, "p"
+ for RCU-preempt, and "s" for RCU-sched, and "N"
+ is the CPU number. This reduces OS jitter on the
offloaded CPUs, which can be useful for HPC and
+
real-time workloads. It can also improve energy
efficiency for asymmetric multiprocessors.
@@ -2461,6 +2564,17 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
leaf rcu_node structure. Useful for very large
systems.
+ rcutree.jiffies_till_first_fqs= [KNL,BOOT]
+ Set delay from grace-period initialization to
+ first attempt to force quiescent states.
+ Units are jiffies, minimum value is zero,
+ and maximum value is HZ.
+
+ rcutree.jiffies_till_next_fqs= [KNL,BOOT]
+ Set delay between subsequent attempts to force
+ quiescent states. Units are jiffies, minimum
+ value is one, and maximum value is HZ.
+
rcutree.qhimark= [KNL,BOOT]
Set threshold of queued
RCU callbacks over which batch limiting is disabled.
@@ -2475,16 +2589,15 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
rcutree.rcu_cpu_stall_timeout= [KNL,BOOT]
Set timeout for RCU CPU stall warning messages.
- rcutree.jiffies_till_first_fqs= [KNL,BOOT]
- Set delay from grace-period initialization to
- first attempt to force quiescent states.
- Units are jiffies, minimum value is zero,
- and maximum value is HZ.
+ rcutree.rcu_idle_gp_delay= [KNL,BOOT]
+ Set wakeup interval for idle CPUs that have
+ RCU callbacks (RCU_FAST_NO_HZ=y).
- rcutree.jiffies_till_next_fqs= [KNL,BOOT]
- Set delay between subsequent attempts to force
- quiescent states. Units are jiffies, minimum
- value is one, and maximum value is HZ.
+ rcutree.rcu_idle_lazy_gp_delay= [KNL,BOOT]
+ Set wakeup interval for idle CPUs that have
+ only "lazy" RCU callbacks (RCU_FAST_NO_HZ=y).
+ Lazy RCU callbacks are those which RCU can
+ prove do nothing more than free memory.
rcutorture.fqs_duration= [KNL,BOOT]
Set duration of force_quiescent_state bursts.
@@ -2637,6 +2750,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
Useful for devices that are detected asynchronously
(e.g. USB and MMC devices).
+ rproc_mem=nn[KMG][@address]
+ [KNL,ARM,CMA] Remoteproc physical memory block.
+ Memory area to be used by remote processor image,
+ managed by CMA.
+
rw [KNL] Mount root device read-write on boot
S [KNL] Run init in single mode
@@ -2890,6 +3008,27 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
Force threading of all interrupt handlers except those
marked explicitly IRQF_NO_THREAD.
+ tmem [KNL,XEN]
+ Enable the Transcendent memory driver if built-in.
+
+ tmem.cleancache=0|1 [KNL, XEN]
+ Default is on (1). Disable the usage of the cleancache
+ API to send anonymous pages to the hypervisor.
+
+ tmem.frontswap=0|1 [KNL, XEN]
+ Default is on (1). Disable the usage of the frontswap
+ API to send swap pages to the hypervisor. If disabled
+ the selfballooning and selfshrinking are force disabled.
+
+ tmem.selfballooning=0|1 [KNL, XEN]
+ Default is on (1). Disable the driving of swap pages
+ to the hypervisor.
+
+ tmem.selfshrinking=0|1 [KNL, XEN]
+ Default is on (1). Partial swapoff that immediately
+ transfers pages from Xen hypervisor back to the
+ kernel based on different criteria.
+
topology= [S390]
Format: {off | on}
Specify if the kernel should make use of the cpu
@@ -3196,6 +3335,15 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
or other driver-specific files in the
Documentation/watchdog/ directory.
+ workqueue.disable_numa
+ By default, all work items queued to unbound
+ workqueues are affine to the NUMA nodes they're
+ issued on, which results in better behavior in
+ general. If NUMA affinity needs to be disabled for
+ whatever reason, this option can be used. Note
+ that this also can be controlled per-workqueue for
+ workqueues visible under /sys/bus/workqueue/.
+
x2apic_phys [X86-64,APIC] Use x2apic physical mode instead of
default x2apic cluster mode on platforms
supporting x2apic.
@@ -3206,9 +3354,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
plus one apbt timer for broadcast timer.
x86_mrst_timer=apbt_only | lapic_and_apbt
- xd= [HW,XT] Original XT pre-IDE (RLL encoded) disks.
- xd_geo= See header of drivers/block/xd.c.
-
xen_emul_unplug= [HW,X86,XEN]
Unplug Xen emulated devices
Format: [unplug0,][unplug1]