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-rw-r--r--Documentation/admin-guide/kernel-parameters.txt54
1 files changed, 53 insertions, 1 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index a827ec820f73..a76d83ed5262 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -1190,6 +1190,11 @@
This is designed to be used in conjunction with
the boot argument: earlyprintk=vga
+ This parameter works in place of the kgdboc parameter
+ but can only be used if the backing tty is available
+ very early in the boot process. For early debugging
+ via a serial port see kgdboc_earlycon instead.
+
edd= [EDD]
Format: {"off" | "on" | "skip[mbr]"}
@@ -1748,6 +1753,13 @@
initrd= [BOOT] Specify the location of the initial ramdisk
+ initrdmem= [KNL] Specify a physical address and size from which to
+ load the initrd. If an initrd is compiled in or
+ specified in the bootparams, it takes priority over this
+ setting.
+ Format: ss[KMG],nn[KMG]
+ Default is 0, 0
+
init_on_alloc= [MM] Fill newly allocated pages and heap objects with
zeroes.
Format: 0 | 1
@@ -2105,6 +2117,21 @@
kms, kbd format: kms,kbd
kms, kbd and serial format: kms,kbd,<ser_dev>[,baud]
+ kgdboc_earlycon= [KGDB,HW]
+ If the boot console provides the ability to read
+ characters and can work in polling mode, you can use
+ this parameter to tell kgdb to use it as a backend
+ until the normal console is registered. Intended to
+ be used together with the kgdboc parameter which
+ specifies the normal console to transition to.
+
+ The name of the early console should be specified
+ as the value of this parameter. Note that the name of
+ the early console might be different than the tty
+ name passed to kgdboc. It's OK to leave the value
+ blank and the first boot console that implements
+ read() will be picked.
+
kgdbwait [KGDB] Stop kernel execution and enter the
kernel debugger at the earliest opportunity.
@@ -3329,7 +3356,7 @@
See Documentation/admin-guide/sysctl/vm.rst for details.
ohci1394_dma=early [HW] enable debugging via the ohci1394 driver.
- See Documentation/debugging-via-ohci1394.txt for more
+ See Documentation/core-api/debugging-via-ohci1394.rst for more
info.
olpc_ec_timeout= [OLPC] ms delay when issuing EC commands
@@ -4210,12 +4237,24 @@
Duration of CPU stall (s) to test RCU CPU stall
warnings, zero to disable.
+ rcutorture.stall_cpu_block= [KNL]
+ Sleep while stalling if set. This will result
+ in warnings from preemptible RCU in addition
+ to any other stall-related activity.
+
rcutorture.stall_cpu_holdoff= [KNL]
Time to wait (s) after boot before inducing stall.
rcutorture.stall_cpu_irqsoff= [KNL]
Disable interrupts while stalling if set.
+ rcutorture.stall_gp_kthread= [KNL]
+ Duration (s) of forced sleep within RCU
+ grace-period kthread to test RCU CPU stall
+ warnings, zero to disable. If both stall_cpu
+ and stall_gp_kthread are specified, the
+ kthread is starved first, then the CPU.
+
rcutorture.stat_interval= [KNL]
Time (s) between statistics printk()s.
@@ -4286,6 +4325,13 @@
only normal grace-period primitives. No effect
on CONFIG_TINY_RCU kernels.
+ rcupdate.rcu_task_ipi_delay= [KNL]
+ Set time in jiffies during which RCU tasks will
+ avoid sending IPIs, starting with the beginning
+ of a given grace period. Setting a large
+ number avoids disturbing real-time workloads,
+ but lengthens grace periods.
+
rcupdate.rcu_task_stall_timeout= [KNL]
Set timeout in jiffies for RCU task stall warning
messages. Disable with a value less than or equal
@@ -5067,6 +5113,12 @@
interruptions from clocksource watchdog are not
acceptable).
+ tsc_early_khz= [X86] Skip early TSC calibration and use the given
+ value instead. Useful when the early TSC frequency discovery
+ procedure is not reliable, such as on overclocked systems
+ with CPUID.16h support and partial CPUID.15h support.
+ Format: <unsigned int>
+
tsx= [X86] Control Transactional Synchronization
Extensions (TSX) feature in Intel processors that
support TSX control.