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-rw-r--r--Documentation/admin-guide/kernel-parameters.txt173
1 files changed, 157 insertions, 16 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 04545725f187..5c949c12ed07 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -50,7 +50,7 @@
CONFIG_ACPI_DEBUG must be enabled to produce any ACPI
debug output. Bits in debug_layer correspond to a
_COMPONENT in an ACPI source file, e.g.,
- #define _COMPONENT ACPI_PCI_COMPONENT
+ #define _COMPONENT ACPI_EVENTS
Bits in debug_level correspond to a level in
ACPI_DEBUG_PRINT statements, e.g.,
ACPI_DEBUG_PRINT((ACPI_DB_INFO, ...
@@ -60,8 +60,6 @@
Enable processor driver info messages:
acpi.debug_layer=0x20000000
- Enable PCI/PCI interrupt routing info messages:
- acpi.debug_layer=0x400000
Enable AML "Debug" output, i.e., stores to the Debug
object while interpreting AML:
acpi.debug_layer=0xffffffff acpi.debug_level=0x2
@@ -784,6 +782,16 @@
cs89x0_media= [HW,NET]
Format: { rj45 | aui | bnc }
+ csdlock_debug= [KNL] Enable debug add-ons of cross-CPU function call
+ handling. When switched on, additional debug data is
+ printed to the console in case a hanging CPU is
+ detected, and that CPU is pinged again in order to try
+ to resolve the hang situation.
+ 0: disable csdlock debugging (default)
+ 1: enable basic csdlock debugging (minor impact)
+ ext: enable extended csdlock debugging (more impact,
+ but more data)
+
dasd= [HW,NET]
See header of drivers/s390/block/dasd_devmap.c.
@@ -2279,8 +2287,7 @@
state is kept private from the host.
Not valid if the kernel is running in EL2.
- Defaults to VHE/nVHE based on hardware support and
- the value of CONFIG_ARM64_VHE.
+ Defaults to VHE/nVHE based on hardware support.
kvm-arm.vgic_v3_group0_trap=
[KVM,ARM] Trap guest accesses to GICv3 group-0
@@ -3472,7 +3479,8 @@
nr_uarts= [SERIAL] maximum number of UARTs to be registered.
- numa_balancing= [KNL,X86] Enable or disable automatic NUMA balancing.
+ numa_balancing= [KNL,ARM64,PPC,RISCV,S390,X86] Enable or disable automatic
+ NUMA balancing.
Allowed values are enable and disable
numa_zonelist_order= [KNL, BOOT] Select zonelist order for NUMA.
@@ -3592,6 +3600,96 @@
Currently this function knows 686a and 8231 chips.
Format: [spp|ps2|epp|ecp|ecpepp]
+ pata_legacy.all= [HW,LIBATA]
+ Format: <int>
+ Set to non-zero to probe primary and secondary ISA
+ port ranges on PCI systems where no PCI PATA device
+ has been found at either range. Disabled by default.
+
+ pata_legacy.autospeed= [HW,LIBATA]
+ Format: <int>
+ Set to non-zero if a chip is present that snoops speed
+ changes. Disabled by default.
+
+ pata_legacy.ht6560a= [HW,LIBATA]
+ Format: <int>
+ Set to 1, 2, or 3 for HT 6560A on the primary channel,
+ the secondary channel, or both channels respectively.
+ Disabled by default.
+
+ pata_legacy.ht6560b= [HW,LIBATA]
+ Format: <int>
+ Set to 1, 2, or 3 for HT 6560B on the primary channel,
+ the secondary channel, or both channels respectively.
+ Disabled by default.
+
+ pata_legacy.iordy_mask= [HW,LIBATA]
+ Format: <int>
+ IORDY enable mask. Set individual bits to allow IORDY
+ for the respective channel. Bit 0 is for the first
+ legacy channel handled by this driver, bit 1 is for
+ the second channel, and so on. The sequence will often
+ correspond to the primary legacy channel, the secondary
+ legacy channel, and so on, but the handling of a PCI
+ bus and the use of other driver options may interfere
+ with the sequence. By default IORDY is allowed across
+ all channels.
+
+ pata_legacy.opti82c46x= [HW,LIBATA]
+ Format: <int>
+ Set to 1, 2, or 3 for Opti 82c611A on the primary
+ channel, the secondary channel, or both channels
+ respectively. Disabled by default.
+
+ pata_legacy.opti82c611a= [HW,LIBATA]
+ Format: <int>
+ Set to 1, 2, or 3 for Opti 82c465MV on the primary
+ channel, the secondary channel, or both channels
+ respectively. Disabled by default.
+
+ pata_legacy.pio_mask= [HW,LIBATA]
+ Format: <int>
+ PIO mode mask for autospeed devices. Set individual
+ bits to allow the use of the respective PIO modes.
+ Bit 0 is for mode 0, bit 1 is for mode 1, and so on.
+ All modes allowed by default.
+
+ pata_legacy.probe_all= [HW,LIBATA]
+ Format: <int>
+ Set to non-zero to probe tertiary and further ISA
+ port ranges on PCI systems. Disabled by default.
+
+ pata_legacy.probe_mask= [HW,LIBATA]
+ Format: <int>
+ Probe mask for legacy ISA PATA ports. Depending on
+ platform configuration and the use of other driver
+ options up to 6 legacy ports are supported: 0x1f0,
+ 0x170, 0x1e8, 0x168, 0x1e0, 0x160, however probing
+ of individual ports can be disabled by setting the
+ corresponding bits in the mask to 1. Bit 0 is for
+ the first port in the list above (0x1f0), and so on.
+ By default all supported ports are probed.
+
+ pata_legacy.qdi= [HW,LIBATA]
+ Format: <int>
+ Set to non-zero to probe QDI controllers. By default
+ set to 1 if CONFIG_PATA_QDI_MODULE, 0 otherwise.
+
+ pata_legacy.winbond= [HW,LIBATA]
+ Format: <int>
+ Set to non-zero to probe Winbond controllers. Use
+ the standard I/O port (0x130) if 1, otherwise the
+ value given is the I/O port to use (typically 0x1b0).
+ By default set to 1 if CONFIG_PATA_WINBOND_VLB_MODULE,
+ 0 otherwise.
+
+ pata_platform.pio_mask= [HW,LIBATA]
+ Format: <int>
+ Supported PIO mode mask. Set individual bits to allow
+ the use of the respective PIO modes. Bit 0 is for
+ mode 0, bit 1 is for mode 1, and so on. Mode 0 only
+ allowed by default.
+
pause_on_oops=
Halt all CPUs after the first oops has been printed for
the specified number of seconds. This is to be used if
@@ -4061,6 +4159,17 @@
fully seed the kernel's CRNG. Default is controlled
by CONFIG_RANDOM_TRUST_CPU.
+ randomize_kstack_offset=
+ [KNL] Enable or disable kernel stack offset
+ randomization, which provides roughly 5 bits of
+ entropy, frustrating memory corruption attacks
+ that depend on stack address determinism or
+ cross-syscall address exposures. This is only
+ available on architectures that have defined
+ CONFIG_HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET.
+ Format: <bool> (1/Y/y=enable, 0/N/n=disable)
+ Default is CONFIG_RANDOMIZE_KSTACK_OFFSET_DEFAULT.
+
ras=option[,option,...] [KNL] RAS-specific options
cec_disable [X86]
@@ -4068,9 +4177,7 @@
see CONFIG_RAS_CEC help text.
rcu_nocbs= [KNL]
- The argument is a cpu list, as described above,
- except that the string "all" can be used to
- specify every CPU on the system.
+ The argument is a cpu list, as described above.
In kernels built with CONFIG_RCU_NOCB_CPU=y, set
the specified list of CPUs to be no-callback CPUs.
@@ -4259,6 +4366,18 @@
rcuscale.kfree_rcu_test= [KNL]
Set to measure performance of kfree_rcu() flooding.
+ rcuscale.kfree_rcu_test_double= [KNL]
+ Test the double-argument variant of kfree_rcu().
+ If this parameter has the same value as
+ rcuscale.kfree_rcu_test_single, both the single-
+ and double-argument variants are tested.
+
+ rcuscale.kfree_rcu_test_single= [KNL]
+ Test the single-argument variant of kfree_rcu().
+ If this parameter has the same value as
+ rcuscale.kfree_rcu_test_double, both the single-
+ and double-argument variants are tested.
+
rcuscale.kfree_nthreads= [KNL]
The number of threads running loops of kfree_rcu().
@@ -4725,7 +4844,7 @@
sbni= [NET] Granch SBNI12 leased line adapter
- sched_debug [KNL] Enables verbose scheduler debug messages.
+ sched_verbose [KNL] Enables verbose scheduler debug messages.
schedstats= [KNL,X86] Enable or disable scheduled statistics.
Allowed values are enable and disable. This feature
@@ -5100,27 +5219,37 @@
spia_peddr=
split_lock_detect=
- [X86] Enable split lock detection
+ [X86] Enable split lock detection or bus lock detection
When enabled (and if hardware support is present), atomic
instructions that access data across cache line
- boundaries will result in an alignment check exception.
+ boundaries will result in an alignment check exception
+ for split lock detection or a debug exception for
+ bus lock detection.
off - not enabled
- warn - the kernel will emit rate limited warnings
+ warn - the kernel will emit rate-limited warnings
about applications triggering the #AC
- exception. This mode is the default on CPUs
- that supports split lock detection.
+ exception or the #DB exception. This mode is
+ the default on CPUs that support split lock
+ detection or bus lock detection. Default
+ behavior is by #AC if both features are
+ enabled in hardware.
fatal - the kernel will send SIGBUS to applications
- that trigger the #AC exception.
+ that trigger the #AC exception or the #DB
+ exception. Default behavior is by #AC if
+ both features are enabled in hardware.
If an #AC exception is hit in the kernel or in
firmware (i.e. not while executing in user mode)
the kernel will oops in either "warn" or "fatal"
mode.
+ #DB exception for bus lock is triggered only when
+ CPL > 0.
+
srbds= [X86,INTEL]
Control the Special Register Buffer Data Sampling
(SRBDS) mitigation.
@@ -5462,6 +5591,18 @@
See Documentation/admin-guide/mm/transhuge.rst
for more details.
+ trusted.source= [KEYS]
+ Format: <string>
+ This parameter identifies the trust source as a backend
+ for trusted keys implementation. Supported trust
+ sources:
+ - "tpm"
+ - "tee"
+ If not specified then it defaults to iterating through
+ the trust source list starting with TPM and assigns the
+ first trust source as a backend which is initialized
+ successfully during iteration.
+
tsc= Disable clocksource stability checks for TSC.
Format: <string>
[x86] reliable: mark tsc clocksource as reliable, this