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-rw-r--r--Documentation/kernel-parameters.txt73
1 files changed, 60 insertions, 13 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 742f69d..168fd79 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -472,6 +472,15 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
Change the amount of debugging information output
when initialising the APIC and IO-APIC components.
+ apic_extnmi= [APIC,X86] External NMI delivery setting
+ Format: { bsp (default) | all | none }
+ bsp: External NMI is delivered only to CPU 0
+ all: External NMIs are broadcast to all CPUs as a
+ backup of CPU 0
+ none: External NMI is masked for all CPUs. This is
+ useful so that a dump capture kernel won't be
+ shot down by NMI
+
autoconf= [IPV6]
See Documentation/networking/ipv6.txt.
@@ -599,6 +608,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
cut the overhead, others just disable the usage. So
only cgroup_disable=memory is actually worthy}
+ cgroup.memory= [KNL] Pass options to the cgroup memory controller.
+ Format: <string>
+ nosocket -- Disable socket memory accounting.
+
checkreqprot [SELINUX] Set initial checkreqprot flag value.
Format: { "0" | "1" }
See security/selinux/Kconfig help text.
@@ -721,16 +734,17 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
uart[8250],io,<addr>[,options]
uart[8250],mmio,<addr>[,options]
+ uart[8250],mmio16,<addr>[,options]
uart[8250],mmio32,<addr>[,options]
uart[8250],0x<addr>[,options]
Start an early, polled-mode console on the 8250/16550
UART at the specified I/O port or MMIO address,
switching to the matching ttyS device later.
MMIO inter-register address stride is either 8-bit
- (mmio) or 32-bit (mmio32).
- If none of [io|mmio|mmio32], <addr> is assumed to be
- equivalent to 'mmio'. 'options' are specified in the
- same format described for ttyS above; if unspecified,
+ (mmio), 16-bit (mmio16), or 32-bit (mmio32).
+ If none of [io|mmio|mmio16|mmio32], <addr> is assumed
+ to be equivalent to 'mmio'. 'options' are specified in
+ the same format described for ttyS above; if unspecified,
the h/w is not re-initialized.
hvc<n> Use the hypervisor console device <n>. This is for
@@ -1002,10 +1016,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
unspecified, the h/w is not initialized.
pl011,<addr>
+ pl011,mmio32,<addr>
Start an early, polled-mode console on a pl011 serial
port at the specified address. The pl011 serial port
must already be setup and configured. Options are not
- yet supported.
+ yet supported. If 'mmio32' is specified, then only
+ the driver will use only 32-bit accessors to read/write
+ the device registers.
msm_serial,<addr>
Start an early, polled-mode console on an msm serial
@@ -2575,8 +2592,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
notsc [BUGS=X86-32] Disable Time Stamp Counter
- nousb [USB] Disable the USB subsystem
-
nowatchdog [KNL] Disable both lockup detectors, i.e.
soft-lockup and NMI watchdog (hard-lockup).
@@ -3296,18 +3311,35 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
rcutorture.verbose= [KNL]
Enable additional printk() statements.
+ rcupdate.rcu_cpu_stall_suppress= [KNL]
+ Suppress RCU CPU stall warning messages.
+
+ rcupdate.rcu_cpu_stall_timeout= [KNL]
+ Set timeout for RCU CPU stall warning messages.
+
rcupdate.rcu_expedited= [KNL]
Use expedited grace-period primitives, for
example, synchronize_rcu_expedited() instead
of synchronize_rcu(). This reduces latency,
but can increase CPU utilization, degrade
real-time latency, and degrade energy efficiency.
-
- rcupdate.rcu_cpu_stall_suppress= [KNL]
- Suppress RCU CPU stall warning messages.
-
- rcupdate.rcu_cpu_stall_timeout= [KNL]
- Set timeout for RCU CPU stall warning messages.
+ No effect on CONFIG_TINY_RCU kernels.
+
+ rcupdate.rcu_normal= [KNL]
+ Use only normal grace-period primitives,
+ for example, synchronize_rcu() instead of
+ synchronize_rcu_expedited(). This improves
+ real-time latency, CPU utilization, and
+ energy efficiency, but can expose users to
+ increased grace-period latency. This parameter
+ overrides rcupdate.rcu_expedited. No effect on
+ CONFIG_TINY_RCU kernels.
+
+ rcupdate.rcu_normal_after_boot= [KNL]
+ Once boot has completed (that is, after
+ rcu_end_inkernel_boot() has been invoked), use
+ only normal grace-period primitives. No effect
+ on CONFIG_TINY_RCU kernels.
rcupdate.rcu_task_stall_timeout= [KNL]
Set timeout in jiffies for RCU task stall warning
@@ -3874,6 +3906,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
usbcore.usbfs_snoop=
[USB] Set to log all usbfs traffic (default 0 = off).
+ usbcore.usbfs_snoop_max=
+ [USB] Maximum number of bytes to snoop in each URB
+ (default = 65536).
+
usbcore.blinkenlights=
[USB] Set to cycle leds on hubs (default 0 = off).
@@ -3894,6 +3930,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
USB_REQ_GET_DESCRIPTOR request in milliseconds
(default 5000 = 5.0 seconds).
+ usbcore.nousb [USB] Disable the USB subsystem
+
usbhid.mousepoll=
[USBHID] The interval which mice are to be polled at.
@@ -4114,6 +4152,15 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
or other driver-specific files in the
Documentation/watchdog/ directory.
+ workqueue.watchdog_thresh=
+ If CONFIG_WQ_WATCHDOG is configured, workqueue can
+ warn stall conditions and dump internal state to
+ help debugging. 0 disables workqueue stall
+ detection; otherwise, it's the stall threshold
+ duration in seconds. The default value is 30 and
+ it can be updated at runtime by writing to the
+ corresponding sysfs file.
+
workqueue.disable_numa
By default, all work items queued to unbound
workqueues are affine to the NUMA nodes they're