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-rw-r--r--Documentation/admin-guide/kernel-parameters.txt92
1 files changed, 86 insertions, 6 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index ea81784be981..4943fc845a15 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -458,6 +458,9 @@
arm64.nomops [ARM64] Unconditionally disable Memory Copy and Memory
Set instructions support
+ arm64.nompam [ARM64] Unconditionally disable Memory Partitioning And
+ Monitoring support
+
arm64.nomte [ARM64] Unconditionally disable Memory Tagging Extension
support
@@ -2535,6 +2538,13 @@
requires the kernel to be built with
CONFIG_ARM64_PSEUDO_NMI.
+ irqchip.riscv_imsic_noipi
+ [RISC-V,EARLY]
+ Force the kernel to not use IMSIC software injected MSIs
+ as IPIs. Intended for system where IMSIC is trap-n-emulated,
+ and thus want to reduce MMIO traps when triggering IPIs
+ to multiple harts.
+
irqfixup [HW]
When an interrupt is not handled search all handlers
for it. Intended to get systems with badly broken
@@ -2749,6 +2759,31 @@
kgdbwait [KGDB,EARLY] Stop kernel execution and enter the
kernel debugger at the earliest opportunity.
+ kho= [KEXEC,EARLY]
+ Format: { "0" | "1" | "off" | "on" | "y" | "n" }
+ Enables or disables Kexec HandOver.
+ "0" | "off" | "n" - kexec handover is disabled
+ "1" | "on" | "y" - kexec handover is enabled
+
+ kho_scratch= [KEXEC,EARLY]
+ Format: ll[KMG],mm[KMG],nn[KMG] | nn%
+ Defines the size of the KHO scratch region. The KHO
+ scratch regions are physically contiguous memory
+ ranges that can only be used for non-kernel
+ allocations. That way, even when memory is heavily
+ fragmented with handed over memory, the kexeced
+ kernel will always have enough contiguous ranges to
+ bootstrap itself.
+
+ It is possible to specify the exact amount of
+ memory in the form of "ll[KMG],mm[KMG],nn[KMG]"
+ where the first parameter defines the size of a low
+ memory scratch area, the second parameter defines
+ the size of a global scratch area and the third
+ parameter defines the size of additional per-node
+ scratch areas. The form "nn%" defines scale factor
+ (in percents) of memory that was used during boot.
+
kmac= [MIPS] Korina ethernet MAC address.
Configure the RouterBoard 532 series on-chip
Ethernet adapter MAC address.
@@ -3762,6 +3797,10 @@
mmio_stale_data=full,nosmt [X86]
retbleed=auto,nosmt [X86]
+ [X86] After one of the above options, additionally
+ supports attack-vector based controls as documented in
+ Documentation/admin-guide/hw-vuln/attack_vector_controls.rst
+
mminit_loglevel=
[KNL,EARLY] When CONFIG_DEBUG_MEMORY_INIT is set, this
parameter allows control of the logging verbosity for
@@ -4972,6 +5011,18 @@
that number, otherwise (e.g., 'pmu_override=on'), MMCR1
remains 0.
+ pm_async= [PM]
+ Format: off
+ This parameter sets the initial value of the
+ /sys/power/pm_async sysfs knob at boot time.
+ If set to "off", disables asynchronous suspend and
+ resume of devices during system-wide power transitions.
+ This can be useful on platforms where device
+ dependencies are not well-defined, or for debugging
+ power management issues. Asynchronous operations are
+ enabled by default.
+
+
pm_debug_messages [SUSPEND,KNL]
Enable suspend/resume debug messages during boot up.
@@ -5457,7 +5508,8 @@
echo 1 > /sys/module/rcutree/parameters/rcu_normal_wake_from_gp
or pass a boot parameter "rcutree.rcu_normal_wake_from_gp=1"
- Default is 0.
+ Default is 1 if num_possible_cpus() <= 16 and it is not explicitly
+ disabled by the boot parameter passing 0.
rcuscale.gp_async= [KNL]
Measure performance of asynchronous
@@ -6359,6 +6411,11 @@
sa1100ir [NET]
See drivers/net/irda/sa1100_ir.c.
+ sched_proxy_exec= [KNL]
+ Enables or disables "proxy execution" style
+ solution to mutex-based priority inversion.
+ Format: <bool>
+
sched_verbose [KNL,EARLY] Enables verbose scheduler debug messages.
schedstats= [KNL,X86] Enable or disable scheduled statistics.
@@ -6530,14 +6587,14 @@
slab_debug can create guard zones around objects and
may poison objects when not in use. Also tracks the
last alloc / free. For more information see
- Documentation/mm/slub.rst.
+ Documentation/admin-guide/mm/slab.rst.
(slub_debug legacy name also accepted for now)
slab_max_order= [MM]
Determines the maximum allowed order for slabs.
A high setting may cause OOMs due to memory
fragmentation. For more information see
- Documentation/mm/slub.rst.
+ Documentation/admin-guide/mm/slab.rst.
(slub_max_order legacy name also accepted for now)
slab_merge [MM]
@@ -6552,13 +6609,14 @@
the number of objects indicated. The higher the number
of objects the smaller the overhead of tracking slabs
and the less frequently locks need to be acquired.
- For more information see Documentation/mm/slub.rst.
+ For more information see
+ Documentation/admin-guide/mm/slab.rst.
(slub_min_objects legacy name also accepted for now)
slab_min_order= [MM]
Determines the minimum page order for slabs. Must be
lower or equal to slab_max_order. For more information see
- Documentation/mm/slub.rst.
+ Documentation/admin-guide/mm/slab.rst.
(slub_min_order legacy name also accepted for now)
slab_nomerge [MM]
@@ -6572,7 +6630,8 @@
cache (risks via metadata attacks are mostly
unchanged). Debug options disable merging on their
own.
- For more information see Documentation/mm/slub.rst.
+ For more information see
+ Documentation/admin-guide/mm/slab.rst.
(slub_nomerge legacy name also accepted for now)
slab_strict_numa [MM]
@@ -7186,6 +7245,14 @@
causing a major performance hit, and the space where
machines are deployed is by other means guarded.
+ tpm_crb_ffa.busy_timeout_ms= [ARM64,TPM]
+ Maximum time in milliseconds to retry sending a message
+ to the TPM service before giving up. This parameter controls
+ how long the system will continue retrying when the TPM
+ service is busy.
+ Format: <unsigned int>
+ Default: 2000 (2 seconds)
+
tpm_suspend_pcr=[HW,TPM]
Format: integer pcr id
Specify that at suspend time, the tpm driver
@@ -7460,6 +7527,19 @@
having this key zero'ed is acceptable. E.g. in testing
scenarios.
+ tsa= [X86] Control mitigation for Transient Scheduler
+ Attacks on AMD CPUs. Search the following in your
+ favourite search engine for more details:
+
+ "Technical guidance for mitigating transient scheduler
+ attacks".
+
+ off - disable the mitigation
+ on - enable the mitigation (default)
+ user - mitigate only user/kernel transitions
+ vm - mitigate only guest/host transitions
+
+
tsc= Disable clocksource stability checks for TSC.
Format: <string>
[x86] reliable: mark tsc clocksource as reliable, this