aboutsummaryrefslogtreecommitdiffstats
path: root/Documentation/admin-guide/kernel-parameters.txt
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/admin-guide/kernel-parameters.txt')
-rw-r--r--Documentation/admin-guide/kernel-parameters.txt80
1 files changed, 70 insertions, 10 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index ade4e6ec23e0..c07815d230bc 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -136,6 +136,10 @@
dynamic table installation which will install SSDT
tables to /sys/firmware/acpi/tables/dynamic.
+ acpi_no_watchdog [HW,ACPI,WDT]
+ Ignore the ACPI-based watchdog interface (WDAT) and let
+ a native driver control the watchdog device instead.
+
acpi_rsdp= [ACPI,EFI,KEXEC]
Pass the RSDP address to the kernel, mostly used
on machines running EFI runtime service to boot the
@@ -437,6 +441,12 @@
no delay (0).
Format: integer
+ bootconfig [KNL]
+ Extended command line options can be added to an initrd
+ and this will cause the kernel to look for it.
+
+ See Documentation/admin-guide/bootconfig.rst
+
bert_disable [ACPI]
Disable BERT OS support on buggy BIOSes.
@@ -511,7 +521,7 @@
1 -- check protection requested by application.
Default value is set via a kernel config option.
Value can be changed at runtime via
- /selinux/checkreqprot.
+ /sys/fs/selinux/checkreqprot.
cio_ignore= [S390]
See Documentation/s390/common_io.rst for details.
@@ -834,6 +844,18 @@
dump out devices still on the deferred probe list after
retrying.
+ dfltcc= [HW,S390]
+ Format: { on | off | def_only | inf_only | always }
+ on: s390 zlib hardware support for compression on
+ level 1 and decompression (default)
+ off: No s390 zlib hardware support
+ def_only: s390 zlib hardware support for deflate
+ only (compression on level 1)
+ inf_only: s390 zlib hardware support for inflate
+ only (decompression)
+ always: Same as 'on' but ignores the selected compression
+ level always using hardware support (used for debugging)
+
dhash_entries= [KNL]
Set number of hash buckets for dentry cache.
@@ -1165,10 +1187,10 @@
efi= [EFI]
Format: { "old_map", "nochunk", "noruntime", "debug",
- "nosoftreserve" }
+ "nosoftreserve", "disable_early_pci_dma",
+ "no_disable_early_pci_dma" }
old_map [X86-64]: switch to the old ioremap-based EFI
- runtime services mapping. 32-bit still uses this one by
- default.
+ runtime services mapping. [Needs CONFIG_X86_UV=y]
nochunk: disable reading files in "chunks" in the EFI
boot stub, as chunking can cause problems with some
firmware implementations.
@@ -1180,6 +1202,10 @@
claim. Specify efi=nosoftreserve to disable this
reservation and treat the memory by its base type
(i.e. EFI_CONVENTIONAL_MEMORY / "System RAM").
+ disable_early_pci_dma: Disable the busmaster bit on all
+ PCI bridges while in the EFI boot stub
+ no_disable_early_pci_dma: Leave the busmaster bit set
+ on all PCI bridges while in the EFI boot stub
efi_no_storage_paranoia [EFI; X86]
Using this parameter you can use more than 50% of
@@ -1245,7 +1271,8 @@
0 -- permissive (log only, no denials).
1 -- enforcing (deny and log).
Default value is 0.
- Value can be changed at runtime via /selinux/enforce.
+ Value can be changed at runtime via
+ /sys/fs/selinux/enforce.
erst_disable [ACPI]
Disable Error Record Serialization Table (ERST)
@@ -1933,9 +1960,31 @@
<cpu number> begins at 0 and the maximum value is
"number of CPUs in system - 1".
- The format of <cpu-list> is described above.
-
+ managed_irq
+
+ Isolate from being targeted by managed interrupts
+ which have an interrupt mask containing isolated
+ CPUs. The affinity of managed interrupts is
+ handled by the kernel and cannot be changed via
+ the /proc/irq/* interfaces.
+
+ This isolation is best effort and only effective
+ if the automatically assigned interrupt mask of a
+ device queue contains isolated and housekeeping
+ CPUs. If housekeeping CPUs are online then such
+ interrupts are directed to the housekeeping CPU
+ so that IO submitted on the housekeeping CPU
+ cannot disturb the isolated CPU.
+
+ If a queue's affinity mask contains only isolated
+ CPUs then this parameter has no effect on the
+ interrupt routing decision, though interrupts are
+ only delivered when tasks running on those
+ isolated CPUs submit IO. IO submitted on
+ housekeeping CPUs has no influence on those
+ queues.
+ The format of <cpu-list> is described above.
iucv= [HW,NET]
@@ -3978,6 +4027,19 @@
test until boot completes in order to avoid
interference.
+ rcuperf.kfree_rcu_test= [KNL]
+ Set to measure performance of kfree_rcu() flooding.
+
+ rcuperf.kfree_nthreads= [KNL]
+ The number of threads running loops of kfree_rcu().
+
+ rcuperf.kfree_alloc_num= [KNL]
+ Number of allocations and frees done in an iteration.
+
+ rcuperf.kfree_loops= [KNL]
+ Number of loops doing rcuperf.kfree_alloc_num number
+ of allocations and frees.
+
rcuperf.nreaders= [KNL]
Set number of RCU readers. The value -1 selects
N, where N is the number of CPUs. A value
@@ -4348,9 +4410,7 @@
See security/selinux/Kconfig help text.
0 -- disable.
1 -- enable.
- Default value is set via kernel config option.
- If enabled at boot time, /selinux/disable can be used
- later to disable prior to initial policy load.
+ Default value is 1.
apparmor= [APPARMOR] Disable or enable AppArmor at boot time
Format: { "0" | "1" }