ALSA ALSA sound support is enabled.
APIC APIC support is enabled.
APM Advanced Power Management support is enabled.
+ ARM ARM architecture is enabled.
AVR32 AVR32 architecture is enabled.
AX25 Appropriate AX.25 support is enabled.
BLACKFIN Blackfin architecture is enabled.
EDD BIOS Enhanced Disk Drive Services (EDD) is enabled
EFI EFI Partitioning (GPT) is enabled
EIDE EIDE/ATAPI support is enabled.
+ EVM Extended Verification Module
FB The frame buffer device is enabled.
+ FTRACE Function tracing enabled.
GCOV GCOV profiling is enabled.
HW Appropriate hardware is enabled.
IA-64 IA-64 architecture is enabled.
Documentation/m68k/kernel-options.txt.
MCA MCA bus support is enabled.
MDA MDA console support is enabled.
+ MIPS MIPS architecture is enabled.
MOUSE Appropriate mouse support is enabled.
MSI Message Signaled Interrupts (PCI).
MTD MTD (Memory Technology Device) support is enabled.
SPARC Sparc architecture is enabled.
SWSUSP Software suspend (hibernation) is enabled.
SUSPEND System suspend states are enabled.
- FTRACE Function tracing enabled.
TPM TPM drivers are enabled.
TS Appropriate touchscreen support is enabled.
UMS USB Mass Storage support is enabled.
X86-64 X86-64 architecture is enabled.
More X86-64 boot options can be found in
Documentation/x86/x86_64/boot-options.txt .
- X86 Either 32bit or 64bit x86 (same as X86-32+X86-64)
+ X86 Either 32-bit or 64-bit x86 (same as X86-32+X86-64)
XEN Xen support is enabled
In addition, the following text indicates that the option:
rsdt -- prefer RSDT over (default) XSDT
copy_dsdt -- copy DSDT to memory
- See also Documentation/power/pm.txt, pci=noacpi
+ 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>
behaviour to be specified. Bit 0 enables warnings,
bit 1 enables fixups, and bit 2 sends a segfault.
+ align_va_addr= [X86-64]
+ Align virtual addresses by clearing slice [14:12] when
+ allocating a VMA at process creation time. This option
+ gives you up to 3% performance improvement on AMD F15h
+ machines (where it is enabled by default) for a
+ CPU-intensive style benchmark, and it can vary highly in
+ a microbenchmark depending on workload and compiler.
+
+ 1: only for 32-bit processes
+ 2: only for 64-bit processes
+ on: enable for both 32- and 64-bit processes
+ off: disable for both 32- and 64-bit processes
+
amd_iommu= [HW,X86-84]
Pass parameters to the AMD IOMMU driver in the system.
Possible values are:
amijoy.map= [HW,JOY] Amiga joystick support
Map of devices attached to JOY0DAT and JOY1DAT
Format: <a>,<b>
- See also Documentation/kernel/input/joystick.txt
+ See also Documentation/input/joystick.txt
analog.map= [HW,JOY] Analog joystick and gamepad support
Specifies type or capabilities of an analog joystick
atkbd.softrepeat= [HW]
Use software keyboard repeat
- autotest [IA64]
+ autotest [IA-64]
baycom_epp= [HW,AX25]
Format: <io>,<mode>
bttv.radio= Most important insmod options are available as
kernel args too.
bttv.pll= See Documentation/video4linux/bttv/Insmod-options
- bttv.tuner= and Documentation/video4linux/bttv/CARDLIST
+ bttv.tuner=
bulk_remove=off [PPC] This parameter disables the use of the pSeries
firmware feature for flushing multiple hpte entries
/proc/<pid>/coredump_filter.
See also Documentation/filesystems/proc.txt.
+ cpuidle.off=1 [CPU_IDLE]
+ disable the cpuidle sub-system
+
cpcihp_generic= [HW,PCI] Generic port I/O CompactPCI driver
Format:
<first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>]
uart[8250],mmio32,<addr>[,options]
Start an early, polled-mode console on the 8250/16550
UART at the specified I/O port or MMIO address.
- MMIO inter-register address stride is either 8bit (mmio)
- or 32bit (mmio32).
+ MMIO inter-register address stride is either 8-bit
+ (mmio) or 32-bit (mmio32).
The options are the same as for ttyS, above.
earlyprintk= [X86,SH,BLACKFIN]
elevator= [IOSCHED]
Format: {"cfq" | "deadline" | "noop"}
- See Documentation/block/as-iosched.txt and
+ See Documentation/block/cfq-iosched.txt and
Documentation/block/deadline-iosched.txt for details.
- elfcorehdr= [IA64,PPC,SH,X86]
+ elfcorehdr= [IA-64,PPC,SH,X86]
Specifies physical address of start of kernel core
image elf header. Generally kexec loader will
pass this option to capture kernel.
This option is obsoleted by the "netdev=" option, which
has equivalent usage. See its documentation for details.
+ evm= [EVM]
+ Format: { "fix" }
+ Permit 'security.evm' to be updated regardless of
+ current integrity status.
+
failslab=
fail_page_alloc=
fail_make_request=[KNL]
General fault injection mechanism.
Format: <interval>,<probability>,<space>,<times>
- See also /Documentation/fault-injection/.
+ See also Documentation/fault-injection/.
floppy= [HW]
See Documentation/blockdev/floppy.txt.
tracer at boot up. function-list is a comma separated
list of functions. This list can be changed at run
time by the set_ftrace_filter file in the debugfs
- tracing directory.
+ tracing directory.
ftrace_notrace=[function-list]
[FTRACE] Do not trace the functions specified in
hashdist= [KNL,NUMA] Large hashes allocated during boot
are distributed across NUMA nodes. Defaults on
- for 64bit NUMA, off otherwise.
+ for 64-bit NUMA, off otherwise.
Format: 0 | 1 (for off | on)
hcl= [IA-64] SGI's Hardware Graph compatibility layer
DMA.
forcedac [x86_64]
With this option iommu will not optimize to look
- for io virtual address below 32 bit forcing dual
+ for io virtual address below 32-bit forcing dual
address cycle on pci bus for cards supporting greater
- than 32 bit addressing. The default is to look
- for translation below 32 bit and if not available
+ than 32-bit addressing. The default is to look
+ for translation below 32-bit and if not available
then look in the higher range.
strict [Default Off]
With this option on every unmap_single operation will
has the capability. With this option, super page will
not be supported.
intremap= [X86-64, Intel-IOMMU]
- Format: { on (default) | off | nosid }
on enable Interrupt Remapping (default)
off disable Interrupt Remapping
nosid disable Source ID checking
+ no_x2apic_optout
+ BIOS x2APIC opt-out request will be ignored
- inttest= [IA64]
+ inttest= [IA-64]
iomem= Disable strict checking of access to MMIO memory
strict regions from userspace.
nomerge
forcesac
soft
- pt [x86, IA64]
+ pt [x86, IA-64]
io7= [HW] IO7 for Marvel based alpha systems
See comment before marvel_specify_io7 in
kvm-amd.npt= [KVM,AMD] Disable nested paging (virtualized MMU)
for all guests.
- Default is 1 (enabled) if in 64bit or 32bit-PAE mode
-
- kvm-intel.bypass_guest_pf=
- [KVM,Intel] Disables bypassing of guest page faults
- on Intel chips. Default is 1 (enabled)
+ Default is 1 (enabled) if in 64-bit or 32-bit PAE mode.
kvm-intel.ept= [KVM,Intel] Disable extended page tables
(virtualized MMU) support on capable Intel chips.
libata.dma=0 Disable all PATA and SATA DMA
libata.dma=1 PATA and SATA Disk DMA only
libata.dma=2 ATAPI (CDROM) DMA only
- libata.dma=4 Compact Flash DMA only
+ libata.dma=4 Compact Flash DMA only
Combinations also work, so libata.dma=3 enables DMA
for disks and CDROMs, but not CFs.
-
+
libata.ignore_hpa= [LIBATA] Ignore HPA limit
libata.ignore_hpa=0 keep BIOS limits (default)
libata.ignore_hpa=1 ignore limits, using full disk
ltpc= [NET]
Format: <io>,<irq>,<dma>
- machvec= [IA64] Force the use of a particular machine-vector
+ machvec= [IA-64] Force the use of a particular machine-vector
(machvec) in a generic kernel.
Example: machvec=hpzx1_swiotlb
it is equivalent to "nosmp", which also disables
the IO APIC.
- max_loop= [LOOP] Maximum number of loopback devices that can
- be mounted
- Format: <1-256>
+ max_loop= [LOOP] The number of loop block devices that get
+ (loop.max_loop) unconditionally pre-created at init time. The default
+ number is configured by BLK_DEV_LOOP_MIN_COUNT. Instead
+ of statically allocating a predefined number, loop
+ devices can be requested on-demand with the
+ /dev/loop-control interface.
mcatest= [IA-64]
nointroute [IA-64]
- nojitter [IA64] Disables jitter checking for ITC timers.
+ nojitter [IA-64] Disables jitter checking for ITC timers.
no-kvmclock [X86,KVM] Disable paravirtualized KVM clock driver
no-kvmapf [X86,KVM] Disable paravirtualized asynchronous page
fault handling.
+ no-steal-acc [X86,KVM] Disable paravirtualized steal time accounting.
+ steal time is computed, but won't influence scheduler
+ behaviour
+
nolapic [X86-32,APIC] Do not enable or use the local APIC.
nolapic_timer [X86-32,APIC] Do not use the local APIC timer.
nox2apic [X86-64,APIC] Do not enable x2APIC mode.
- nptcg= [IA64] Override max number of concurrent global TLB
+ nptcg= [IA-64] Override max number of concurrent global TLB
purges which is reported from either PAL_VM_SUMMARY or
SAL PALO.
See Documentation/sound/oss/oss-parameters.txt
panic= [KNL] Kernel behaviour on panic: delay <timeout>
- seconds before rebooting
+ timeout > 0: seconds before rebooting
+ timeout = 0: wait forever
+ timeout < 0: reboot immediately
Format: <timeout>
parkbd.port= [HW] Parallel port number the keyboard adapter is
Format: { parport<nr> | timid | 0 }
See also Documentation/parport.txt.
- pmtmr= [X86] Manual setup of pmtmr I/O Port.
+ pmtmr= [X86] Manual setup of pmtmr I/O Port.
Override pmtimer IOPort with a hex value.
e.g. pmtmr=0x508
- pnp.debug [PNP]
- Enable PNP debug messages. This depends on the
- CONFIG_PNP_DEBUG_MESSAGES option.
+ pnp.debug=1 [PNP]
+ Enable PNP debug messages (depends on the
+ CONFIG_PNP_DEBUG_MESSAGES option). Change at run-time
+ via /sys/module/pnp/parameters/debug. We always show
+ current resource usage; turning this on also shows
+ possible settings and some assignment information.
pnpacpi= [ACPI]
{ off }
[HW,MOUSE] Controls Logitech smartscroll autorepeat.
0 = disabled, 1 = enabled (default).
+ pstore.backend= Specify the name of the pstore backend to use
+
pt. [PARIDE]
See Documentation/blockdev/paride.txt.
in <PAGE_SIZE> units (needed only for swap files).
See Documentation/power/swsusp-and-swap-files.txt
+ resumedelay= [HIBERNATION] Delay (in seconds) to pause before attempting to
+ read the resume files
+
+ resumewait [HIBERNATION] Wait (indefinitely) for resume device to show up.
+ Useful for devices that are detected asynchronously
+ (e.g. USB and MMC devices).
+
hibernate= [HIBERNATION]
noresume Don't check if there's a hibernation image
present during boot.
ro [KNL] Mount root device read-only on boot
root= [KNL] Root filesystem
+ See name_to_dev_t comment in init/do_mounts.c.
rootdelay= [KNL] Delay (in seconds) to pause before attempting to
mount the root filesystem
Format: <integer>
sonypi.*= [HW] Sony Programmable I/O Control Device driver
- See Documentation/sonypi.txt
+ See Documentation/laptops/sonypi.txt
specialix= [HW,SERIAL] Specialix multi-serial port adapter
See Documentation/serial/specialix.txt.
<port#>,<js1>,<js2>,<js3>,<js4>,<js5>,<js6>,<js7>
See also Documentation/input/joystick-parport.txt
+ udbg-immortal [PPC] When debugging early kernel crashes that
+ happen after console_init() and before a proper
+ console driver takes over, this boot options might
+ help "seeing" what's going on.
+
uhash_entries= [KNL,NET]
Set number of hash buckets for UDP/UDP-Lite connections
unknown_nmi_panic
[X86] Cause panic on unknown NMI.
+ usbcore.authorized_default=
+ [USB] Default USB device authorization:
+ (default -1 = authorized except for wireless USB,
+ 0 = not authorized, 1 = authorized)
+
usbcore.autosuspend=
[USB] The autosuspend time delay (in seconds) used
for newly-detected USB devices (default 2). This
medium is write-protected).
Example: quirks=0419:aaf5:rl,0421:0433:rc
+ user_debug= [KNL,ARM]
+ Format: <int>
+ See arch/arm/Kconfig.debug help text.
+ 1 - undefined instruction events
+ 2 - system calls
+ 4 - invalid data aborts
+ 8 - SIGSEGV faults
+ 16 - SIGBUS faults
+ Example: user_debug=31
+
userpte=
[X86] Flags controlling user PTE allocations.
vmpoff= [KNL,S390] Perform z/VM CP command after power off.
Format: <command>
+ vsyscall= [X86-64]
+ Controls the behavior of vsyscalls (i.e. calls to
+ fixed addresses of 0xffffffffff600x00 from legacy
+ code). Most statically-linked binaries and older
+ versions of glibc use these calls. Because these
+ functions are at fixed addresses, they make nice
+ targets for exploits that can control RIP.
+
+ emulate Vsyscalls turn into traps and are emulated
+ reasonably safely.
+
+ native [default] 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.
+
+ none Vsyscalls don't work at all. This makes
+ them quite hard to use for exploits but
+ might break your system.
+
vt.cur_default= [VT] Default cursor shape.
Format: 0xCCBBAA, where AA, BB, and CC are the same as
the parameters of the <Esc>[?A;B;Cc escape sequence;