ACPI_DEBUG_PRINT statements, e.g.,
ACPI_DEBUG_PRINT((ACPI_DB_INFO, ...
The debug_level mask defaults to "info". See
- Documentation/acpi/debug.txt for more information about
+ Documentation/firmware-guide/acpi/debug.rst for more information about
debug layers and levels.
Enable processor driver info messages:
others).
ccw_timeout_log [S390]
- See Documentation/s390/CommonIO for details.
+ See Documentation/s390/common_io.rst for details.
cgroup_disable= [KNL] Disable a particular controller
Format: {name of the controller(s) to disable}
/selinux/checkreqprot.
cio_ignore= [S390]
- See Documentation/s390/CommonIO for details.
+ See Documentation/s390/common_io.rst for details.
clk_ignore_unused
[CLK]
Prevents the clock framework from automatically gating
[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.txt for further details.
+ See Documentation/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.txt for an example.
+ Documentation/kdump/kdump.rst for an example.
crashkernel=size[KMG],high
[KNL, x86_64] range could be above 4G. Allow kernel
tracking down these problems.
debug_pagealloc=
- [KNL] When CONFIG_DEBUG_PAGEALLOC is set, this
- parameter enables the feature at boot time. In
- default, it is disabled. We can avoid allocating huge
- chunk of memory for debug pagealloc if we don't enable
- it at boot time and the system will work mostly same
- with the kernel built without CONFIG_DEBUG_PAGEALLOC.
+ [KNL] When CONFIG_DEBUG_PAGEALLOC is set, this parameter
+ enables the feature at boot time. By default, it is
+ disabled and the system will work mostly the same as a
+ kernel built without CONFIG_DEBUG_PAGEALLOC.
on: enable the feature
debugpat [X86] Enable PAT debugging
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.txt. An EDID
+ available in Documentation/EDID/howto.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
for details.
nompx [X86] Disables Intel Memory Protection Extensions.
- See Documentation/x86/intel_mpx.txt for more
+ See Documentation/x86/intel_mpx.rst for more
information about the feature.
nopku [X86] Disable Memory Protection Keys CPU feature found
that is to be dynamically loaded by Linux. If there are
multiple variables with the same name but with different
vendor GUIDs, all of them will be loaded. See
- Documentation/acpi/ssdt-overlays.txt for details.
+ Documentation/admin-guide/acpi/ssdt-overlays.rst for details.
eisa_irq_edge= [PARISC,HW]
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.txt for details.
+ See Documentation/kdump/kdump.rst for details.
enable_mtrr_cleanup [X86]
The kernel tries to adjust MTRR layout from continuous
Valid parameters: "on", "off"
Default: "on"
- hisax= [HW,ISDN]
- See Documentation/isdn/README.HiSax.
-
hlt [BUGS=ARM,SH]
hpet= [X86-32,HPET] option to control HPET usage
Format: =0.0 to prevent dma on hda, =0.1 hdb =1.0 hdc
.vlb_clock .pci_clock .noflush .nohpa .noprobe .nowerr
.cdrom .chs .ignore_cable are additional options
- See Documentation/ide/ide.txt.
+ See Documentation/ide/ide.rst.
ide-generic.probe-mask= [HW] (E)IDE subsystem
Format: <int>
mce [X86-32] Machine Check Exception
- mce=option [X86-64] See Documentation/x86/x86_64/boot-options.txt
+ mce=option [X86-64] See Documentation/x86/x86_64/boot-options.rst
md= [HW] RAID subsystems devices and level
See Documentation/admin-guide/md.rst.
set according to the
CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE kernel config
option.
- See Documentation/memory-hotplug.txt.
+ See Documentation/admin-guide/mm/memory-hotplug.rst.
memmap=exactmap [KNL,X86] Enable setting of an exact
E820 memory map, as specified by the user.
mem_encrypt=on: Activate SME
mem_encrypt=off: Do not activate SME
- Refer to Documentation/x86/amd-memory-encryption.txt
+ Refer to Documentation/virtual/kvm/amd-memory-encryption.rst
for details on when memory encryption can be activated.
mem_sleep_default= [SUSPEND] Default system suspend mode:
0 - turn hardlockup detector in nmi_watchdog off
1 - turn hardlockup detector in nmi_watchdog on
When panic is specified, panic when an NMI watchdog
- timeout occurs (or 'nopanic' to override the opposite
- default). To disable both hard and soft lockup detectors,
+ timeout occurs (or 'nopanic' to not panic on an NMI
+ watchdog, if CONFIG_BOOTPARAM_HARDLOCKUP_PANIC is set)
+ To disable both hard and soft lockup detectors,
please see 'nowatchdog'.
This is useful when you use a panic=... timeout and
need the box quickly up again.
See Documentation/blockdev/paride.txt.
pirq= [SMP,APIC] Manual mp-table setup
- See Documentation/x86/i386/IO-APIC.txt.
+ See Documentation/x86/i386/IO-APIC.rst.
plip= [PPT,NET] Parallel port network link
Format: { parport<nr> | timid | 0 }
the propagation of recent CPU-hotplug changes up
the rcu_node combining tree.
+ rcutree.use_softirq= [KNL]
+ If set to zero, move all RCU_SOFTIRQ processing to
+ per-CPU rcuc kthreads. Defaults to a non-zero
+ value, meaning that RCU_SOFTIRQ is used by default.
+ Specify rcutree.use_softirq=0 to use rcuc kthreads.
+
rcutree.rcu_fanout_exact= [KNL]
Disable autobalancing of the rcu_node combining
tree. This is used by rcutorture, and might
relax_domain_level=
[KNL, SMP] Set scheduler's default relax_domain_level.
- See Documentation/cgroup-v1/cpusets.txt.
+ See Documentation/cgroup-v1/cpusets.rst.
reserve= [KNL,BUGS] Force kernel to ignore I/O ports or memory
Format: <base1>,<size1>[,<base2>,<size2>,...]
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.txt)
+ it if 0 is given (See Documentation/cgroup-v1/memory.rst)
swiotlb= [ARM,IA-64,PPC,MIPS,X86]
Format: { <int> | force | noforce }
vector=percpu: enable percpu vector domain
video= [FB] Frame buffer configuration
- See Documentation/fb/modedb.txt.
+ See Documentation/fb/modedb.rst.
video.brightness_switch_enabled= [0,1]
If set to 1, on receiving an ACPI notify event
Can be used multiple times for multiple devices.
vga= [BOOT,X86-32] Select a particular video mode
- See Documentation/x86/boot.txt and
+ See Documentation/x86/boot.rst and
Documentation/svga.txt.
Use vga=ask for menu.
This is actually a boot loader parameter; the value is
targets for exploits that can control RIP.
emulate [default] Vsyscalls turn into traps and are
- emulated reasonably safely.
+ emulated reasonably safely. The vsyscall
+ page is readable.
- native Vsyscalls are native syscall instructions.
- This is a little bit faster than trapping
- and makes a few dynamic recompilers work
- better than they would in emulation mode.
- It also makes exploits much easier to write.
+ xonly Vsyscalls turn into traps and are
+ emulated reasonably safely. The vsyscall
+ page is not readable.
none Vsyscalls don't work at all. This makes
them quite hard to use for exploits but
Default: 3 = cyan.
watchdog timers [HW,WDT] For information on watchdog timers,
- see Documentation/watchdog/watchdog-parameters.txt
+ see Documentation/watchdog/watchdog-parameters.rst
or other driver-specific files in the
Documentation/watchdog/ directory.