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-rw-r--r--Documentation/admin-guide/kernel-parameters.txt62
1 files changed, 45 insertions, 17 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index f2633dd87a97..31b3a25680d0 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -1,3 +1,14 @@
+ accept_memory= [MM]
+ Format: { eager | lazy }
+ default: lazy
+ By default, unaccepted memory is accepted lazily to
+ avoid prolonged boot times. The lazy option will add
+ some runtime overhead until all memory is eventually
+ accepted. In most cases the overhead is negligible.
+ For some workloads or for debugging purposes
+ accept_memory=eager can be used to accept all memory
+ at once during boot.
+
acpi= [HW,ACPI,X86,ARM64,RISCV64]
Advanced Configuration and Power Interface
Format: { force | on | off | strict | noirq | rsdt |
@@ -972,17 +983,17 @@
buddy allocator. Bigger value increase the probability
of catching random memory corruption, but reduce the
amount of memory for normal system use. The maximum
- possible value is MAX_ORDER/2. Setting this parameter
- to 1 or 2 should be enough to identify most random
- memory corruption problems caused by bugs in kernel or
- driver code when a CPU writes to (or reads from) a
- random memory location. Note that there exists a class
- of memory corruptions problems caused by buggy H/W or
- F/W or by drivers badly programming DMA (basically when
- memory is written at bus level and the CPU MMU is
- bypassed) which are not detectable by
- CONFIG_DEBUG_PAGEALLOC, hence this option will not help
- tracking down these problems.
+ possible value is MAX_PAGE_ORDER/2. Setting this
+ parameter to 1 or 2 should be enough to identify most
+ random memory corruption problems caused by bugs in
+ kernel or driver code when a CPU writes to (or reads
+ from) a random memory location. Note that there exists
+ a class of memory corruptions problems caused by buggy
+ H/W or F/W or by drivers badly programming DMA
+ (basically when memory is written at bus level and the
+ CPU MMU is bypassed) which are not detectable by
+ CONFIG_DEBUG_PAGEALLOC, hence this option will not
+ help tracking down these problems.
debug_pagealloc=
[KNL] When CONFIG_DEBUG_PAGEALLOC is set, this parameter
@@ -2440,7 +2451,7 @@
between unregistering the boot console and initializing
the real console.
- keepinitrd [HW,ARM]
+ keepinitrd [HW,ARM] See retain_initrd.
kernelcore= [KNL,X86,IA-64,PPC]
Format: nn[KMGTPE] | nn% | "mirror"
@@ -3987,9 +3998,9 @@
vulnerability. System may allow data leaks with this
option.
- no-steal-acc [X86,PV_OPS,ARM64,PPC/PSERIES] Disable paravirtualized
- steal time accounting. steal time is computed, but
- won't influence scheduler behaviour
+ no-steal-acc [X86,PV_OPS,ARM64,PPC/PSERIES,RISCV] Disable
+ paravirtualized steal time accounting. steal time is
+ computed, but won't influence scheduler behaviour
nosync [HW,M68K] Disables sync negotiation for all devices.
@@ -4138,7 +4149,7 @@
[KNL] Minimal page reporting order
Format: <integer>
Adjust the minimal page reporting order. The page
- reporting is disabled when it exceeds MAX_ORDER.
+ reporting is disabled when it exceeds MAX_PAGE_ORDER.
panic= [KNL] Kernel behaviour on panic: delay <timeout>
timeout > 0: seconds before rebooting
@@ -5304,6 +5315,12 @@
Dump ftrace buffer after reporting RCU CPU
stall warning.
+ rcupdate.rcu_cpu_stall_notifiers= [KNL]
+ Provide RCU CPU stall notifiers, but see the
+ warnings in the RCU_CPU_STALL_NOTIFIER Kconfig
+ option's help text. TL;DR: You almost certainly
+ do not want rcupdate.rcu_cpu_stall_notifiers.
+
rcupdate.rcu_cpu_stall_suppress= [KNL]
Suppress RCU CPU stall warning messages.
@@ -5546,6 +5563,13 @@
print every Nth verbose statement, where N is the value
specified.
+ regulator_ignore_unused
+ [REGULATOR]
+ Prevents regulator framework from disabling regulators
+ that are unused, due no driver claiming them. This may
+ be useful for debug and development, but should not be
+ needed on a platform with proper driver support.
+
relax_domain_level=
[KNL, SMP] Set scheduler's default relax_domain_level.
See Documentation/admin-guide/cgroup-v1/cpusets.rst.
@@ -5582,7 +5606,8 @@
Useful for devices that are detected asynchronously
(e.g. USB and MMC devices).
- retain_initrd [RAM] Keep initrd memory after extraction
+ retain_initrd [RAM] Keep initrd memory after extraction. After boot, it will
+ be accessible via /sys/firmware/initrd.
retbleed= [X86] Control mitigation of RETBleed (Arbitrary
Speculative Code Execution with Return Instructions)
@@ -6910,6 +6935,9 @@
pause after every control message);
o = USB_QUIRK_HUB_SLOW_RESET (Hub needs extra
delay after resetting its port);
+ p = USB_QUIRK_SHORT_SET_ADDRESS_REQ_TIMEOUT
+ (Reduce timeout of the SET_ADDRESS
+ request from 5000 ms to 500 ms);
Example: quirks=0781:5580:bk,0a5c:5834:gij
usbhid.mousepoll=