This facility can be used to prevent such uncontrolled
GPE floodings.
Format: <int>
- Support masking of GPEs numbered from 0x00 to 0x7f.
acpi_no_auto_serialize [HW,ACPI]
Disable auto-serialization of AML methods
acpi_sleep= [HW,ACPI] Sleep options
Format: { s3_bios, s3_mode, s3_beep, s4_nohwsig,
- old_ordering, nonvs, sci_force_enable }
+ old_ordering, nonvs, sci_force_enable, nobl }
See Documentation/power/video.txt for information on
s3_bios and s3_mode.
s3_beep is for debugging; it makes the PC's speaker beep
sci_force_enable causes the kernel to set SCI_EN directly
on resume from S1/S3 (which is against the ACPI spec,
but some broken systems don't work without it).
+ nobl causes the internal blacklist of systems known to
+ behave incorrectly in some ways with respect to system
+ suspend and resume to be ignored (use wisely).
acpi_use_timer_override [HW,ACPI]
Use timer override. For some broken Nvidia NF5 boards
console=brl,ttyS0
For now, only VisioBraille is supported.
+ console_msg_format=
+ [KNL] Change console messages format
+ default
+ By default we print messages on consoles in
+ "[time stamp] text\n" format (time stamp may not be
+ printed, depending on CONFIG_PRINTK_TIME or
+ `printk_time' param).
+ syslog
+ Switch to syslog format: "<%u>[time stamp] text\n"
+ IOW, each message will have a facility and loglevel
+ prefix. The format is similar to one used by syslog()
+ syscall, or to executing "dmesg -S --raw" or to reading
+ from /proc/kmsg.
+
consoleblank= [KNL] The console blank (screen saver) timeout in
seconds. A value of 0 disables the blank timer.
Defaults to 0.
It will be ignored when crashkernel=X,high is not used
or memory reserved is below 4G.
- crossrelease_fullstack
- [KNL] Allow to record full stack trace in cross-release
-
cryptomgr.notests
[KNL] Disable crypto self-tests
earlycon= [KNL] Output early console device and options.
- When used with no options, the early console is
- determined by the stdout-path property in device
- tree's chosen node.
+ [ARM64] The early console is determined by the
+ stdout-path property in device tree's chosen node,
+ or determined by the ACPI SPCR table.
+
+ [X86] When used with no options the early console is
+ determined by the ACPI SPCR table.
cdns,<addr>[,options]
Start an early, polled-mode console on a Cadence
This tests the locking primitive's ability to
transition abruptly to and from idle.
- locktorture.torture_runnable= [BOOT]
- Start locktorture running at boot time.
-
locktorture.torture_type= [KNL]
Specify the locking implementation to test.
This is useful when you use a panic=... timeout and
need the box quickly up again.
+ These settings can be accessed at runtime via
+ the nmi_watchdog and hardlockup_panic sysctls.
+
netpoll.carrier_timeout=
[NET] Specifies amount of time (in seconds) that
netpoll should wait for a carrier. By default netpoll
nosmt [KNL,S390] Disable symmetric multithreading (SMT).
Equivalent to smt=1.
+ nospectre_v2 [X86] Disable all mitigations for the Spectre variant 2
+ (indirect branch prediction) vulnerability. System may
+ allow data leaks with this option, which is equivalent
+ to spectre_v2=off.
+
noxsave [BUGS=X86] Disables x86 extended register state save
and restore using xsave. The kernel will fallback to
enabling legacy floating-point and sse state.
steal time is computed, but won't influence scheduler
behaviour
- nopti [X86-64] Disable kernel page table isolation
-
nolapic [X86-32,APIC] Do not enable or use the local APIC.
nolapic_timer [X86-32,APIC] Do not use the local APIC timer.
norandmaps Don't use address space randomization. Equivalent to
echo 0 > /proc/sys/kernel/randomize_va_space
- noreplace-paravirt [X86,IA-64,PV_OPS] Don't patch paravirt_ops
-
noreplace-smp [X86-32,SMP] Don't replace SMP instructions
with UP alternatives
pcie_scan_all Scan all possible PCIe devices. Otherwise we
only look for one device below a PCIe downstream
port.
+ big_root_window Try to add a big 64bit memory window to the PCIe
+ root complex on AMD CPUs. Some GFX hardware
+ can resize a BAR to allow access to all VRAM.
+ Adding the window is slightly risky (it may
+ conflict with unreported devices), so this
+ taints the kernel.
pcie_aspm= [PCIE] Forcibly enable or disable PCIe Active State Power
Management.
pt. [PARIDE]
See Documentation/blockdev/paride.txt.
- pti= [X86_64]
- Control user/kernel address space isolation:
- on - enable
- off - disable
- auto - default setting
+ pti= [X86_64] Control Page Table Isolation of user and
+ kernel address spaces. Disabling this feature
+ removes hardening, but improves performance of
+ system calls and interrupts.
+
+ on - unconditionally enable
+ off - unconditionally disable
+ auto - kernel detects whether your CPU model is
+ vulnerable to issues that PTI mitigates
+
+ Not specifying this option is equivalent to pti=auto.
+
+ nopti [X86_64]
+ Equivalent to pti=off
pty.legacy_count=
[KNL] Number of legacy pty's. Overwrites compiled-in
the same as for rcuperf.nreaders.
N, where N is the number of CPUs
- rcuperf.perf_runnable= [BOOT]
- Start rcuperf running at boot time.
-
rcuperf.perf_type= [KNL]
Specify the RCU implementation to test.
Test RCU's dyntick-idle handling. See also the
rcutorture.shuffle_interval parameter.
- rcutorture.torture_runnable= [BOOT]
- Start rcutorture running at boot time.
-
rcutorture.torture_type= [KNL]
Specify the RCU implementation to test.
rdt= [HW,X86,RDT]
Turn on/off individual RDT features. List is:
- cmt, mbmtotal, mbmlocal, l3cat, l3cdp, l2cat, mba.
+ cmt, mbmtotal, mbmlocal, l3cat, l3cdp, l2cat, l2cdp,
+ mba.
E.g. to turn on cmt and turn off mba use:
rdt=cmt,!mba
[KNL, SMP] Set scheduler's default relax_domain_level.
See Documentation/cgroup-v1/cpusets.txt.
- reserve= [KNL,BUGS] Force the kernel to ignore some iomem area
+ reserve= [KNL,BUGS] Force kernel to ignore I/O ports or memory
+ Format: <base1>,<size1>[,<base2>,<size2>,...]
+ Reserve I/O ports or memory so the kernel won't use
+ them. If <base> is less than 0x10000, the region
+ is assumed to be I/O ports; otherwise it is memory.
reservetop= [X86-32]
Format: nn[KMG]
sonypi.*= [HW] Sony Programmable I/O Control Device driver
See Documentation/laptops/sonypi.txt
+ spectre_v2= [X86] Control mitigation of Spectre variant 2
+ (indirect branch speculation) vulnerability.
+
+ on - unconditionally enable
+ off - unconditionally disable
+ auto - kernel detects whether your CPU model is
+ vulnerable
+
+ Selecting 'on' will, and 'auto' may, choose a
+ mitigation method at run time according to the
+ CPU, the available microcode, the setting of the
+ CONFIG_RETPOLINE configuration option, and the
+ compiler with which the kernel was built.
+
+ Specific mitigations can also be selected manually:
+
+ retpoline - replace indirect branches
+ retpoline,generic - google's original retpoline
+ retpoline,amd - AMD-specific minimal thunk
+
+ Not specifying this option is equivalent to
+ spectre_v2=auto.
+
spia_io_base= [HW,MTD]
spia_fio_base=
spia_pedr=
git.samba.org / sfrench / cifs-2.6.git / blobdiff