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-rw-r--r--Documentation/kernel-parameters.txt132
1 files changed, 122 insertions, 10 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index f3a89fac2202..fcc48bf722a8 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -89,7 +89,9 @@ parameter is applicable:
SPARC Sparc architecture is enabled.
SWSUSP Software suspend (hibernation) is enabled.
SUSPEND System suspend states are enabled.
+ FTRACE Function tracing enabled.
TS Appropriate touchscreen support is enabled.
+ UMS USB Mass Storage support is enabled.
USB USB support is enabled.
USBHID USB Human Interface Device support is enabled.
V4L Video For Linux support is enabled.
@@ -473,8 +475,8 @@ and is between 256 and 4096 characters. It is defined in the file
clearcpuid=BITNUM [X86]
Disable CPUID feature X for the kernel. See
- include/asm-x86/cpufeature.h for the valid bit numbers.
- Note the Linux specific bits are not necessarily
+ arch/x86/include/asm/cpufeature.h for the valid bit
+ numbers. Note the Linux specific bits are not necessarily
stable over kernel options, but the vendor specific
ones should be.
Also note that user programs calling CPUID directly
@@ -555,6 +557,11 @@ and is between 256 and 4096 characters. It is defined in the file
not work reliably with all consoles, but is known
to work with serial and VGA consoles.
+ coredump_filter=
+ [KNL] Change the default value for
+ /proc/<pid>/coredump_filter.
+ See also Documentation/filesystems/proc.txt.
+
cpcihp_generic= [HW,PCI] Generic port I/O CompactPCI driver
Format:
<first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>]
@@ -758,6 +765,14 @@ and is between 256 and 4096 characters. It is defined in the file
parameter will force ia64_sal_cache_flush to call
ia64_pal_cache_flush instead of SAL_CACHE_FLUSH.
+ ftrace=[tracer]
+ [ftrace] will set and start the specified tracer
+ as early as possible in order to facilitate early
+ boot debugging.
+
+ ftrace_dump_on_oops
+ [ftrace] will dump the trace buffers on oops.
+
gamecon.map[2|3]=
[HW,JOY] Multisystem joystick and NES/SNES/PSX pad
support via parallel port (up to 5 devices per port)
@@ -819,6 +834,9 @@ and is between 256 and 4096 characters. It is defined in the file
hlt [BUGS=ARM,SH]
+ hvc_iucv= [S390] Number of z/VM IUCV Hypervisor console (HVC)
+ back-ends. Valid parameters: 0..8
+
i8042.debug [HW] Toggle i8042 debug mode
i8042.direct [HW] Put keyboard port into non-translated mode
i8042.dumbkbd [HW] Pretend that controller can only read data from
@@ -908,6 +926,10 @@ and is between 256 and 4096 characters. It is defined in the file
inttest= [IA64]
+ iomem= Disable strict checking of access to MMIO memory
+ strict regions from userspace.
+ relaxed
+
iommu= [x86]
off
force
@@ -1112,6 +1134,8 @@ and is between 256 and 4096 characters. It is defined in the file
If there are multiple matching configurations changing
the same attribute, the last one is used.
+ lmb=debug [KNL] Enable lmb debug messages.
+
load_ramdisk= [RAM] List of ramdisks to load from floppy
See Documentation/blockdev/ramdisk.txt.
@@ -1403,7 +1427,20 @@ and is between 256 and 4096 characters. It is defined in the file
when a NMI is triggered.
Format: [state][,regs][,debounce][,die]
- nmi_watchdog= [KNL,BUGS=X86-32] Debugging features for SMP kernels
+ nmi_watchdog= [KNL,BUGS=X86-32,X86-64] Debugging features for SMP kernels
+ Format: [panic,][num]
+ Valid num: 0,1,2
+ 0 - turn nmi_watchdog off
+ 1 - use the IO-APIC timer for the NMI watchdog
+ 2 - use the local APIC for the NMI watchdog using
+ a performance counter. Note: This will use one performance
+ counter and the local APIC's performance vector.
+ When panic is specified panic when an NMI watchdog timeout occurs.
+ This is useful when you use a panic=... timeout and need the box
+ quickly up again.
+ Instead of 1 and 2 it is possible to use the following
+ symbolic names: lapic and ioapic
+ Example: nmi_watchdog=2 or nmi_watchdog=panic,lapic
no387 [BUGS=X86-32] Tells the kernel to use the 387 maths
emulation library even if a 387 maths coprocessor
@@ -1459,6 +1496,10 @@ and is between 256 and 4096 characters. It is defined in the file
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.
+
nohalt [IA-64] Tells the kernel not to use the power saving
function PAL_HALT_LIGHT when idle. This increases
power-consumption. On the positive side, it reduces
@@ -1528,6 +1569,9 @@ and is between 256 and 4096 characters. It is defined in the file
nosoftlockup [KNL] Disable the soft-lockup detector.
+ noswapaccount [KNL] Disable accounting of swap in memory resource
+ controller. (See Documentation/controllers/memory.txt)
+
nosync [HW,M68K] Disables sync negotiation for all devices.
notsc [BUGS=X86-32] Disable Time Stamp Counter
@@ -1547,6 +1591,10 @@ and is between 256 and 4096 characters. It is defined in the file
nr_uarts= [SERIAL] maximum number of UARTs to be registered.
+ ohci1394_dma=early [HW] enable debugging via the ohci1394 driver.
+ See Documentation/debugging-via-ohci1394.txt for more
+ info.
+
olpc_ec_timeout= [OLPC] ms delay when issuing EC commands
Rather than timing out after 20 ms if an EC
command is not properly ACKed, override the length
@@ -1636,6 +1684,17 @@ and is between 256 and 4096 characters. It is defined in the file
nomsi [MSI] If the PCI_MSI kernel config parameter is
enabled, this kernel boot option can be used to
disable the use of MSI interrupts system-wide.
+ noioapicquirk [APIC] Disable all boot interrupt quirks.
+ Safety option to keep boot IRQs enabled. This
+ should never be necessary.
+ ioapicreroute [APIC] Enable rerouting of boot IRQs to the
+ primary IO-APIC for bridges that cannot disable
+ boot IRQs. This fixes a source of spurious IRQs
+ when the system masks IRQs.
+ noioapicreroute [APIC] Disable workaround that uses the
+ boot IRQ equivalent of an IRQ that connects to
+ a chipset where boot IRQs cannot be disabled.
+ The opposite of ioapicreroute.
biosirq [X86-32] Use PCI BIOS calls to get the interrupt
routing table. These calls are known to be buggy
on several machines and they hang the machine
@@ -1760,10 +1819,10 @@ and is between 256 and 4096 characters. It is defined in the file
autoconfiguration.
Ranges are in pairs (memory base and size).
- dynamic_printk
- Enables pr_debug()/dev_dbg() calls if
- CONFIG_DYNAMIC_PRINTK_DEBUG has been enabled. These can also
- be switched on/off via <debugfs>/dynamic_printk/modules
+ dynamic_printk Enables pr_debug()/dev_dbg() calls if
+ CONFIG_DYNAMIC_PRINTK_DEBUG has been enabled.
+ These can also be switched on/off via
+ <debugfs>/dynamic_printk/modules
print-fatal-signals=
[KNL] debug: print fatal signals
@@ -1851,7 +1910,7 @@ and is between 256 and 4096 characters. It is defined in the file
reboot= [BUGS=X86-32,BUGS=ARM,BUGS=IA-64] Rebooting mode
Format: <reboot_mode>[,<reboot_mode2>[,...]]
- See arch/*/kernel/reboot.c or arch/*/kernel/process.c
+ See arch/*/kernel/reboot.c or arch/*/kernel/process.c
relax_domain_level=
[KNL, SMP] Set scheduler's default relax_domain_level.
@@ -2175,6 +2234,9 @@ and is between 256 and 4096 characters. It is defined in the file
st= [HW,SCSI] SCSI tape parameters (buffers, etc.)
See Documentation/scsi/st.txt.
+ stacktrace [FTRACE]
+ Enabled the stack tracer on boot up.
+
sti= [PARISC,HW]
Format: <num>
Set the STI (builtin display/keyboard on the HP-PARISC
@@ -2260,12 +2322,27 @@ and is between 256 and 4096 characters. It is defined in the file
See comment before function dc390_setup() in
drivers/scsi/tmscsim.c.
+ topology= [S390]
+ Format: {off | on}
+ Specify if the kernel should make use of the cpu
+ topology informations if the hardware supports these.
+ The scheduler will make use of these informations and
+ e.g. base its process migration decisions on it.
+ Default is off.
+
tp720= [HW,PS2]
trix= [HW,OSS] MediaTrix AudioTrix Pro
Format:
<io>,<irq>,<dma>,<dma2>,<sb_io>,<sb_irq>,<sb_dma>,<mpu_io>,<mpu_irq>
+ tsc= Disable clocksource-must-verify flag for TSC.
+ Format: <string>
+ [x86] reliable: mark tsc clocksource as reliable, this
+ disables clocksource verification at runtime.
+ Used to enable high-resolution timer mode on older
+ hardware, and in virtualized environment.
+
turbografx.map[2|3]= [HW,JOY]
TurboGraFX parallel port interface
Format:
@@ -2322,6 +2399,41 @@ and is between 256 and 4096 characters. It is defined in the file
usbhid.mousepoll=
[USBHID] The interval which mice are to be polled at.
+ usb-storage.delay_use=
+ [UMS] The delay in seconds before a new device is
+ scanned for Logical Units (default 5).
+
+ usb-storage.quirks=
+ [UMS] A list of quirks entries to supplement or
+ override the built-in unusual_devs list. List
+ entries are separated by commas. Each entry has
+ the form VID:PID:Flags where VID and PID are Vendor
+ and Product ID values (4-digit hex numbers) and
+ Flags is a set of characters, each corresponding
+ to a common usb-storage quirk flag as follows:
+ a = SANE_SENSE (collect more than 18 bytes
+ of sense data);
+ c = FIX_CAPACITY (decrease the reported
+ device capacity by one sector);
+ h = CAPACITY_HEURISTICS (decrease the
+ reported device capacity by one
+ sector if the number is odd);
+ i = IGNORE_DEVICE (don't bind to this
+ device);
+ l = NOT_LOCKABLE (don't try to lock and
+ unlock ejectable media);
+ m = MAX_SECTORS_64 (don't transfer more
+ than 64 sectors = 32 KB at a time);
+ o = CAPACITY_OK (accept the capacity
+ reported by the device);
+ r = IGNORE_RESIDUE (the device reports
+ bogus residue values);
+ s = SINGLE_LUN (the device has only one
+ Logical Unit);
+ w = NO_WP_DETECT (don't test whether the
+ medium is write-protected).
+ Example: quirks=0419:aaf5:rl,0421:0433:rc
+
add_efi_memmap [EFI; x86-32,X86-64] Include EFI memory map in
kernel's map of available physical RAM.
@@ -2382,8 +2494,8 @@ and is between 256 and 4096 characters. It is defined in the file
Format:
<irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
- norandmaps Don't use address space randomization
- Equivalent to echo 0 > /proc/sys/kernel/randomize_va_space
+ norandmaps Don't use address space randomization. Equivalent to
+ echo 0 > /proc/sys/kernel/randomize_va_space
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