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-rw-r--r--Documentation/admin-guide/kernel-parameters.txt113
1 files changed, 66 insertions, 47 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 099c5a4be95b..46b826fcb5ad 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -13,7 +13,7 @@
For ARM64, ONLY "acpi=off", "acpi=on" or "acpi=force"
are available
- See also Documentation/power/runtime_pm.txt, pci=noacpi
+ See also Documentation/power/runtime_pm.rst, pci=noacpi
acpi_apic_instance= [ACPI, IOAPIC]
Format: <int>
@@ -223,7 +223,7 @@
acpi_sleep= [HW,ACPI] Sleep options
Format: { s3_bios, s3_mode, s3_beep, s4_nohwsig,
old_ordering, nonvs, sci_force_enable, nobl }
- See Documentation/power/video.txt for information on
+ See Documentation/power/video.rst for information on
s3_bios and s3_mode.
s3_beep is for debugging; it makes the PC's speaker beep
as soon as the kernel's real-mode entry point is called.
@@ -430,7 +430,7 @@
blkdevparts= Manual partition parsing of block device(s) for
embedded devices based on command line input.
- See Documentation/block/cmdline-partition.txt
+ See Documentation/block/cmdline-partition.rst
boot_delay= Milliseconds to delay each printk during boot.
Values larger than 10 seconds (10000) are changed to
@@ -708,14 +708,14 @@
[KNL, x86_64] select a region under 4G first, and
fall back to reserve region above 4G when '@offset'
hasn't been specified.
- See Documentation/kdump/kdump.rst for further details.
+ See Documentation/admin-guide/kdump/kdump.rst for further details.
crashkernel=range1:size1[,range2:size2,...][@offset]
[KNL] Same as above, but depends on the memory
in the running system. The syntax of range is
start-[end] where start and end are both
a memory unit (amount[KMG]). See also
- Documentation/kdump/kdump.rst for an example.
+ Documentation/admin-guide/kdump/kdump.rst for an example.
crashkernel=size[KMG],high
[KNL, x86_64] range could be above 4G. Allow kernel
@@ -930,7 +930,7 @@
edid/1680x1050.bin, or edid/1920x1080.bin is given
and no file with the same name exists. Details and
instructions how to build your own EDID data are
- available in Documentation/EDID/howto.rst. An EDID
+ available in Documentation/driver-api/edid.rst. An EDID
data set will only be used for a particular connector,
if its name and a colon are prepended to the EDID
name. Each connector may use a unique EDID data
@@ -1199,15 +1199,15 @@
elevator= [IOSCHED]
Format: { "mq-deadline" | "kyber" | "bfq" }
- See Documentation/block/deadline-iosched.txt,
- Documentation/block/kyber-iosched.txt and
- Documentation/block/bfq-iosched.txt for details.
+ See Documentation/block/deadline-iosched.rst,
+ Documentation/block/kyber-iosched.rst and
+ Documentation/block/bfq-iosched.rst for details.
elfcorehdr=[size[KMG]@]offset[KMG] [IA64,PPC,SH,X86,S390]
Specifies physical address of start of kernel core
image elf header and optionally the size. Generally
kexec loader will pass this option to capture kernel.
- See Documentation/kdump/kdump.rst for details.
+ See Documentation/admin-guide/kdump/kdump.rst for details.
enable_mtrr_cleanup [X86]
The kernel tries to adjust MTRR layout from continuous
@@ -1249,7 +1249,7 @@
See also Documentation/fault-injection/.
floppy= [HW]
- See Documentation/blockdev/floppy.txt.
+ See Documentation/admin-guide/blockdev/floppy.rst.
force_pal_cache_flush
[IA-64] Avoid check_sal_cache_flush which may hang on
@@ -2011,6 +2011,19 @@
Built with CONFIG_DEBUG_KMEMLEAK_DEFAULT_OFF=y,
the default is off.
+ kprobe_event=[probe-list]
+ [FTRACE] Add kprobe events and enable at boot time.
+ The probe-list is a semicolon delimited list of probe
+ definitions. Each definition is same as kprobe_events
+ interface, but the parameters are comma delimited.
+ For example, to add a kprobe event on vfs_read with
+ arg1 and arg2, add to the command line;
+
+ kprobe_event=p,vfs_read,$arg1,$arg2
+
+ See also Documentation/trace/kprobetrace.rst "Kernel
+ Boot Parameter" section.
+
kpti= [ARM64] Control page table isolation of user
and kernel address spaces.
Default: enabled on cores which need mitigation.
@@ -2234,7 +2247,7 @@
memblock=debug [KNL] Enable memblock debug messages.
load_ramdisk= [RAM] List of ramdisks to load from floppy
- See Documentation/blockdev/ramdisk.txt.
+ See Documentation/admin-guide/blockdev/ramdisk.rst.
lockd.nlm_grace_period=P [NFS] Assign grace period.
Format: <integer>
@@ -2877,6 +2890,17 @@
/sys/module/printk/parameters/console_suspend) to
turn on/off it dynamically.
+ novmcoredd [KNL,KDUMP]
+ Disable device dump. Device dump allows drivers to
+ append dump data to vmcore so you can collect driver
+ specified debug info. Drivers can append the data
+ without any limit and this data is stored in memory,
+ so this may cause significant memory stress. Disabling
+ device dump can help save memory but the driver debug
+ data will be no longer available. This parameter
+ is only available when CONFIG_PROC_VMCORE_DEVICE_DUMP
+ is set.
+
noaliencache [MM, NUMA, SLAB] Disables the allocation of alien
caches in the slab allocator. Saves per-node memory,
but will impact performance.
@@ -2932,7 +2956,7 @@
register save and restore. The kernel will only save
legacy floating-point registers on task switch.
- nohugeiomap [KNL,x86] Disable kernel huge I/O mappings.
+ nohugeiomap [KNL,x86,PPC] Disable kernel huge I/O mappings.
nosmt [KNL,S390] Disable symmetric multithreading (SMT).
Equivalent to smt=1.
@@ -3144,7 +3168,7 @@
numa_zonelist_order= [KNL, BOOT] Select zonelist order for NUMA.
'node', 'default' can be specified
This can be set from sysctl after boot.
- See Documentation/sysctl/vm.txt for details.
+ See Documentation/admin-guide/sysctl/vm.rst for details.
ohci1394_dma=early [HW] enable debugging via the ohci1394 driver.
See Documentation/debugging-via-ohci1394.txt for more
@@ -3268,7 +3292,7 @@
pcd. [PARIDE]
See header of drivers/block/paride/pcd.c.
- See also Documentation/blockdev/paride.txt.
+ See also Documentation/admin-guide/blockdev/paride.rst.
pci=option[,option...] [PCI] various PCI subsystem options.
@@ -3512,7 +3536,7 @@
needed on a platform with proper driver support.
pd. [PARIDE]
- See Documentation/blockdev/paride.txt.
+ See Documentation/admin-guide/blockdev/paride.rst.
pdcchassis= [PARISC,HW] Disable/Enable PDC Chassis Status codes at
boot time.
@@ -3527,10 +3551,10 @@
and performance comparison.
pf. [PARIDE]
- See Documentation/blockdev/paride.txt.
+ See Documentation/admin-guide/blockdev/paride.rst.
pg. [PARIDE]
- See Documentation/blockdev/paride.txt.
+ See Documentation/admin-guide/blockdev/paride.rst.
pirq= [SMP,APIC] Manual mp-table setup
See Documentation/x86/i386/IO-APIC.rst.
@@ -3642,7 +3666,7 @@
prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk
before loading.
- See Documentation/blockdev/ramdisk.txt.
+ See Documentation/admin-guide/blockdev/ramdisk.rst.
psi= [KNL] Enable or disable pressure stall information
tracking.
@@ -3664,7 +3688,7 @@
pstore.backend= Specify the name of the pstore backend to use
pt. [PARIDE]
- See Documentation/blockdev/paride.txt.
+ See Documentation/admin-guide/blockdev/paride.rst.
pti= [X86_64] Control Page Table Isolation of user and
kernel address spaces. Disabling this feature
@@ -3693,7 +3717,7 @@
See Documentation/admin-guide/md.rst.
ramdisk_size= [RAM] Sizes of RAM disks in kilobytes
- See Documentation/blockdev/ramdisk.txt.
+ See Documentation/admin-guide/blockdev/ramdisk.rst.
random.trust_cpu={on,off}
[KNL] Enable or disable trusting the use of the
@@ -4089,7 +4113,7 @@
relax_domain_level=
[KNL, SMP] Set scheduler's default relax_domain_level.
- See Documentation/cgroup-v1/cpusets.rst.
+ See Documentation/admin-guide/cgroup-v1/cpusets.rst.
reserve= [KNL,BUGS] Force kernel to ignore I/O ports or memory
Format: <base1>,<size1>[,<base2>,<size2>,...]
@@ -4119,7 +4143,7 @@
Specify the offset from the beginning of the partition
given by "resume=" at which the swap header is located,
in <PAGE_SIZE> units (needed only for swap files).
- See Documentation/power/swsusp-and-swap-files.txt
+ See Documentation/power/swsusp-and-swap-files.rst
resumedelay= [HIBERNATION] Delay (in seconds) to pause before attempting to
read the resume files
@@ -4347,7 +4371,7 @@
Format: <integer>
sonypi.*= [HW] Sony Programmable I/O Control Device driver
- See Documentation/laptops/sonypi.txt
+ See Documentation/admin-guide/laptops/sonypi.rst
spectre_v2= [X86] Control mitigation of Spectre variant 2
(indirect branch speculation) vulnerability.
@@ -4599,7 +4623,7 @@
swapaccount=[0|1]
[KNL] Enable accounting of swap in memory resource
controller if no parameter or 1 is given or disable
- it if 0 is given (See Documentation/cgroup-v1/memory.rst)
+ it if 0 is given (See Documentation/admin-guide/cgroup-v1/memory.rst)
swiotlb= [ARM,IA-64,PPC,MIPS,X86]
Format: { <int> | force | noforce }
@@ -4674,27 +4698,6 @@
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
@@ -5066,7 +5069,7 @@
vga= [BOOT,X86-32] Select a particular video mode
See Documentation/x86/boot.rst and
- Documentation/svga.txt.
+ Documentation/admin-guide/svga.rst.
Use vga=ask for menu.
This is actually a boot loader parameter; the value is
passed to the kernel using a special protocol.
@@ -5264,6 +5267,8 @@
xen_nopv [X86]
Disables the PV optimizations forcing the HVM guest to
run as generic HVM guest with no PV drivers.
+ This option is obsoleted by the "nopv" option, which
+ has equivalent effect for XEN platform.
xen_scrub_pages= [XEN]
Boolean option to control scrubbing pages before giving them back
@@ -5278,10 +5283,24 @@
improve timer resolution at the expense of processing
more timer interrupts.
+ nopv= [X86,XEN,KVM,HYPER_V,VMWARE]
+ Disables the PV optimizations forcing the guest to run
+ as generic guest with no PV drivers. Currently support
+ XEN HVM, KVM, HYPER_V and VMWARE guest.
+
xirc2ps_cs= [NET,PCMCIA]
Format:
<irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
+ xive= [PPC]
+ By default on POWER9 and above, the kernel will
+ natively use the XIVE interrupt controller. This option
+ allows the fallback firmware mode to be used:
+
+ off Fallback to firmware control of XIVE interrupt
+ controller on both pseries and powernv
+ platforms. Only useful on POWER9 and above.
+
xhci-hcd.quirks [USB,KNL]
A hex value specifying bitmask with supplemental xhci
host controller quirks. Meaning of each bit can be