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-rw-r--r--Documentation/kernel-parameters.txt56
1 files changed, 46 insertions, 10 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 89835a4..c357a31 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -144,6 +144,11 @@ a fixed number of characters. This limit depends on the architecture
and is between 256 and 4096 characters. It is defined in the file
./include/asm/setup.h as COMMAND_LINE_SIZE.
+Finally, the [KMG] suffix is commonly described after a number of kernel
+parameter values. These 'K', 'M', and 'G' letters represent the _binary_
+multipliers 'Kilo', 'Mega', and 'Giga', equalling 2^10, 2^20, and 2^30
+bytes respectively. Such letter suffixes can also be entirely omitted.
+
acpi= [HW,ACPI,X86]
Advanced Configuration and Power Interface
@@ -545,16 +550,20 @@ and is between 256 and 4096 characters. It is defined in the file
Format:
<first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>]
- crashkernel=nn[KMG]@ss[KMG]
- [KNL] Reserve a chunk of physical memory to
- hold a kernel to switch to with kexec on panic.
+ crashkernel=size[KMG][@offset[KMG]]
+ [KNL] Using kexec, Linux can switch to a 'crash kernel'
+ upon panic. This parameter reserves the physical
+ memory region [offset, offset + size] for that kernel
+ image. If '@offset' is omitted, then a suitable offset
+ is selected automatically. Check
+ Documentation/kdump/kdump.txt 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 a example.
+ Documentation/kdump/kdump.txt for an example.
cs89x0_dma= [HW,NET]
Format: <dma>
@@ -617,6 +626,10 @@ and is between 256 and 4096 characters. It is defined in the file
disable= [IPV6]
See Documentation/networking/ipv6.txt.
+ disable_ddw [PPC/PSERIES]
+ Disable Dynamic DMA Window support. Use this if
+ to workaround buggy firmware.
+
disable_ipv6= [IPV6]
See Documentation/networking/ipv6.txt.
@@ -859,6 +872,12 @@ and is between 256 and 4096 characters. It is defined in the file
If specified, z/VM IUCV HVC accepts connections
from listed z/VM user IDs only.
+ keep_bootcon [KNL]
+ Do not unregister boot console at start. This is only
+ useful for debugging when something happens in the window
+ between unregistering the boot console and initializing
+ the real console.
+
i2c_bus= [HW] Override the default board specific I2C bus speed
or register an additional I2C bus that is not
registered from board initialization code.
@@ -1262,10 +1281,9 @@ and is between 256 and 4096 characters. It is defined in the file
6 (KERN_INFO) informational
7 (KERN_DEBUG) debug-level messages
- log_buf_len=n Sets the size of the printk ring buffer, in bytes.
- Format: { n | nk | nM }
- n must be a power of two. The default size
- is set in the kernel config file.
+ log_buf_len=n[KMG] Sets the size of the printk ring buffer,
+ in bytes. n must be a power of two. The default
+ size is set in the kernel config file.
logo.nologo [FB] Disables display of the built-in Linux logo.
This may be used to provide more screen space for
@@ -1572,16 +1590,25 @@ and is between 256 and 4096 characters. It is defined in the file
of returning the full 64-bit number.
The default is to return 64-bit inode numbers.
+ nfs.nfs4_disable_idmapping=
+ [NFSv4] When set, this option disables the NFSv4
+ idmapper on the client, but only if the mount
+ is using the 'sec=sys' security flavour. This may
+ make migration from legacy NFSv2/v3 systems easier
+ provided that the server has the appropriate support.
+ The default is to always enable NFSv4 idmapping.
+
nmi_debug= [KNL,AVR32,SH] Specify one or more actions to take
when a NMI is triggered.
Format: [state][,regs][,debounce][,die]
nmi_watchdog= [KNL,BUGS=X86] Debugging features for SMP kernels
- Format: [panic,][num]
+ Format: [panic,][nopanic,][num]
Valid num: 0
0 - turn nmi_watchdog off
When panic is specified, panic when an NMI watchdog
- timeout occurs.
+ timeout occurs (or 'nopanic' to override the opposite
+ default).
This is useful when you use a panic=... timeout and
need the box quickly up again.
@@ -1805,6 +1832,11 @@ and is between 256 and 4096 characters. It is defined in the file
perfmon on Intel CPUs instead of the
CPU specific event set.
+ oops=panic Always panic on oopses. Default is to just kill the process,
+ but there is a small probability of deadlocking the machine.
+ This will also cause panics on machine check exceptions.
+ Useful together with panic=30 to trigger a reboot.
+
OSS [HW,OSS]
See Documentation/sound/oss/oss-parameters.txt
@@ -2436,6 +2468,10 @@ and is between 256 and 4096 characters. It is defined in the file
<deci-seconds>: poll all this frequency
0: no polling (default)
+ threadirqs [KNL]
+ Force threading of all interrupt handlers except those
+ marked explicitely IRQF_NO_THREAD.
+
topology= [S390]
Format: {off | on}
Specify if the kernel should make use of the cpu