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-rw-r--r--Documentation/kernel-parameters.txt72
1 files changed, 57 insertions, 15 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index f81afd315..ffad13fdf 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -167,7 +167,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
acpi= [HW,ACPI,X86,ARM64]
Advanced Configuration and Power Interface
- Format: { force | off | strict | noirq | rsdt }
+ Format: { force | off | strict | noirq | rsdt |
+ copy_dsdt }
force -- enable ACPI if default was off
off -- disable ACPI if default was on
noirq -- do not use ACPI for IRQ routing
@@ -789,8 +790,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
is passed, kernel could allocate physical memory region
above 4G, that cause second kernel crash on system
that require some amount of low memory, e.g. swiotlb
- requires at least 64M+32K low memory. Kernel would
- try to allocate 72M below 4G automatically.
+ requires at least 64M+32K low memory, also enough extra
+ low memory is needed to make sure DMA buffers for 32-bit
+ devices won't run out. Kernel would try to allocate at
+ at least 256M below 4G automatically.
This one let user to specify own low range under 4G
for second kernel instead.
0: to disable low allocation.
@@ -929,11 +932,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
The filter can be disabled or changed to another
driver later using sysfs.
- drm_kms_helper.edid_firmware=[<connector>:]<file>
- Broken monitors, graphic adapters and KVMs may
- send no or incorrect EDID data sets. This parameter
- allows to specify an EDID data set in the
- /lib/firmware directory that is used instead.
+ drm_kms_helper.edid_firmware=[<connector>:]<file>[,[<connector>:]<file>]
+ Broken monitors, graphic adapters, KVMs and EDIDless
+ panels may send no or incorrect EDID data sets.
+ This parameter allows to specify an EDID data sets
+ in the /lib/firmware directory that are used instead.
Generic built-in EDID data sets are used, if one of
edid/1024x768.bin, edid/1280x1024.bin,
edid/1680x1050.bin, or edid/1920x1080.bin is given
@@ -942,7 +945,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
available in Documentation/EDID/HOWTO.txt. An EDID
data set will only be used for a particular connector,
if its name and a colon are prepended to the EDID
- name.
+ name. Each connector may use a unique EDID data
+ set by separating the files with a comma. An EDID
+ data set with no connector name will be used for
+ any connectors not explicitly specified.
dscc4.setup= [NET]
@@ -971,6 +977,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
earlycon= [KNL] Output early console device and options.
+ When used with no options, the early console is
+ determined by the stdout-path property in device
+ tree's chosen node.
+
cdns,<addr>
Start an early, polled-mode console on a cadence serial
port at the specified address. The cadence serial port
@@ -1023,6 +1033,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
serial port must already be setup and configured.
Options are not yet supported.
+ lpuart,<addr>
+ lpuart32,<addr>
+ Use early console provided by Freescale LP UART driver
+ found on Freescale Vybrid and QorIQ LS1021A processors.
+ A valid base address must be provided, and the serial
+ port must already be setup and configured.
+
earlyprintk= [X86,SH,BLACKFIN,ARM,M68k]
earlyprintk=vga
earlyprintk=efi
@@ -1094,6 +1111,21 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
you are really sure that your UEFI does sane gc and
fulfills the spec otherwise your board may brick.
+ efi_fake_mem= nn[KMG]@ss[KMG]:aa[,nn[KMG]@ss[KMG]:aa,..] [EFI; X86]
+ Add arbitrary attribute to specific memory range by
+ updating original EFI memory map.
+ Region of memory which aa attribute is added to is
+ from ss to ss+nn.
+ If efi_fake_mem=2G@4G:0x10000,2G@0x10a0000000:0x10000
+ is specified, EFI_MEMORY_MORE_RELIABLE(0x10000)
+ attribute is added to range 0x100000000-0x180000000 and
+ 0x10a0000000-0x1120000000.
+
+ Using this parameter you can do debugging of EFI memmap
+ related feature. For example, you can do debugging of
+ Address Range Mirroring feature even if your box
+ doesn't support it.
+
eisa_irq_edge= [PARISC,HW]
See header of drivers/parisc/eisa.c.
@@ -1246,6 +1278,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
Format: <unsigned int> such that (rxsize & ~0x1fffc0) == 0.
Default: 1024
+ hardlockup_all_cpu_backtrace=
+ [KNL] Should the hard-lockup detector generate
+ backtraces on all cpus.
+ Format: <integer>
+
hashdist= [KNL,NUMA] Large hashes allocated during boot
are distributed across NUMA nodes. Defaults on
for 64-bit NUMA, off otherwise.
@@ -1553,6 +1590,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
nosid disable Source ID checking
no_x2apic_optout
BIOS x2APIC opt-out request will be ignored
+ nopost disable Interrupt Posting
iomem= Disable strict checking of access to MMIO memory
strict regions from userspace.
@@ -2314,11 +2352,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
nmi_watchdog= [KNL,BUGS=X86] Debugging features for SMP kernels
Format: [panic,][nopanic,][num]
Valid num: 0 or 1
- 0 - turn nmi_watchdog off
- 1 - turn nmi_watchdog on
+ 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).
+ default). 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.
@@ -3074,9 +3113,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
cache-to-cache transfer latencies.
rcutree.rcu_fanout_leaf= [KNL]
- Increase the number of CPUs assigned to each
- leaf rcu_node structure. Useful for very large
- systems.
+ Change the number of CPUs assigned to each
+ leaf rcu_node structure. Useful for very
+ large systems, which will choose the value 64,
+ and for NUMA systems with large remote-access
+ latencies, which will choose a value aligned
+ with the appropriate hardware boundaries.
rcutree.jiffies_till_sched_qs= [KNL]
Set required age in jiffies for a