![Andi Kleen](/assets/img/avatar_default.png)
Don't log machine check events left over from boot. Too many BIOSes leave bogus events in there. This unfortunately also makes it impossible to log events that caused a reboot. For people with non broken BIOS there is mce=bootlog Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
191 lines
6.1 KiB
Plaintext
191 lines
6.1 KiB
Plaintext
AMD64 specific boot options
|
|
|
|
There are many others (usually documented in driver documentation), but
|
|
only the AMD64 specific ones are listed here.
|
|
|
|
Machine check
|
|
|
|
mce=off disable machine check
|
|
mce=bootlog Enable logging of machine checks left over from booting.
|
|
Disabled by default because some BIOS leave bogus ones.
|
|
If your BIOS doesn't do that it's a good idea to enable though
|
|
to make sure you log even machine check events that result
|
|
in a reboot.
|
|
|
|
nomce (for compatibility with i386): same as mce=off
|
|
|
|
Everything else is in sysfs now.
|
|
|
|
APICs
|
|
|
|
apic Use IO-APIC. Default
|
|
|
|
noapic Don't use the IO-APIC.
|
|
|
|
disableapic Don't use the local APIC
|
|
|
|
nolapic Don't use the local APIC (alias for i386 compatibility)
|
|
|
|
pirq=... See Documentation/i386/IO-APIC.txt
|
|
|
|
noapictimer Don't set up the APIC timer
|
|
|
|
no_timer_check Don't check the IO-APIC timer. This can work around
|
|
problems with incorrect timer initialization on some boards.
|
|
|
|
Early Console
|
|
|
|
syntax: earlyprintk=vga
|
|
earlyprintk=serial[,ttySn[,baudrate]]
|
|
|
|
The early console is useful when the kernel crashes before the
|
|
normal console is initialized. It is not enabled by
|
|
default because it has some cosmetic problems.
|
|
Append ,keep to not disable it when the real console takes over.
|
|
Only vga or serial at a time, not both.
|
|
Currently only ttyS0 and ttyS1 are supported.
|
|
Interaction with the standard serial driver is not very good.
|
|
The VGA output is eventually overwritten by the real console.
|
|
|
|
Timing
|
|
|
|
notsc
|
|
Don't use the CPU time stamp counter to read the wall time.
|
|
This can be used to work around timing problems on multiprocessor systems
|
|
with not properly synchronized CPUs.
|
|
|
|
report_lost_ticks
|
|
Report when timer interrupts are lost because some code turned off
|
|
interrupts for too long.
|
|
|
|
nmi_watchdog=NUMBER[,panic]
|
|
NUMBER can be:
|
|
0 don't use an NMI watchdog
|
|
1 use the IO-APIC timer for the NMI watchdog
|
|
2 use the local APIC for the NMI watchdog using a performance counter. Note
|
|
This will use one performance counter and the local APIC's performance
|
|
vector.
|
|
When panic is specified panic when an NMI watchdog timeout occurs.
|
|
This is useful when you use a panic=... timeout and need the box
|
|
quickly up again.
|
|
|
|
nohpet
|
|
Don't use the HPET timer.
|
|
|
|
Idle loop
|
|
|
|
idle=poll
|
|
Don't do power saving in the idle loop using HLT, but poll for rescheduling
|
|
event. This will make the CPUs eat a lot more power, but may be useful
|
|
to get slightly better performance in multiprocessor benchmarks. It also
|
|
makes some profiling using performance counters more accurate.
|
|
Please note that on systems with MONITOR/MWAIT support (like Intel EM64T
|
|
CPUs) this option has no performance advantage over the normal idle loop.
|
|
It may also interact badly with hyperthreading.
|
|
|
|
Rebooting
|
|
|
|
reboot=b[ios] | t[riple] | k[bd] [, [w]arm | [c]old]
|
|
bios Use the CPU reboto vector for warm reset
|
|
warm Don't set the cold reboot flag
|
|
cold Set the cold reboot flag
|
|
triple Force a triple fault (init)
|
|
kbd Use the keyboard controller. cold reset (default)
|
|
|
|
Using warm reset will be much faster especially on big memory
|
|
systems because the BIOS will not go through the memory check.
|
|
Disadvantage is that not all hardware will be completely reinitialized
|
|
on reboot so there may be boot problems on some systems.
|
|
|
|
reboot=force
|
|
|
|
Don't stop other CPUs on reboot. This can make reboot more reliable
|
|
in some cases.
|
|
|
|
Non Executable Mappings
|
|
|
|
noexec=on|off
|
|
|
|
on Enable(default)
|
|
off Disable
|
|
|
|
SMP
|
|
|
|
nosmp Only use a single CPU
|
|
|
|
maxcpus=NUMBER only use upto NUMBER CPUs
|
|
|
|
cpumask=MASK only use cpus with bits set in mask
|
|
|
|
NUMA
|
|
|
|
numa=off Only set up a single NUMA node spanning all memory.
|
|
|
|
numa=noacpi Don't parse the SRAT table for NUMA setup
|
|
|
|
numa=fake=X Fake X nodes and ignore NUMA setup of the actual machine.
|
|
|
|
ACPI
|
|
|
|
acpi=off Don't enable ACPI
|
|
acpi=ht Use ACPI boot table parsing, but don't enable ACPI
|
|
interpreter
|
|
acpi=force Force ACPI on (currently not needed)
|
|
|
|
acpi=strict Disable out of spec ACPI workarounds.
|
|
|
|
acpi_sci={edge,level,high,low} Set up ACPI SCI interrupt.
|
|
|
|
acpi=noirq Don't route interrupts
|
|
|
|
PCI
|
|
|
|
pci=off Don't use PCI
|
|
pci=conf1 Use conf1 access.
|
|
pci=conf2 Use conf2 access.
|
|
pci=rom Assign ROMs.
|
|
pci=assign-busses Assign busses
|
|
pci=irqmask=MASK Set PCI interrupt mask to MASK
|
|
pci=lastbus=NUMBER Scan upto NUMBER busses, no matter what the mptable says.
|
|
pci=noacpi Don't use ACPI to set up PCI interrupt routing.
|
|
|
|
IOMMU
|
|
|
|
iommu=[size][,noagp][,off][,force][,noforce][,leak][,memaper[=order]][,merge]
|
|
[,forcesac][,fullflush][,nomerge][,noaperture]
|
|
size set size of iommu (in bytes)
|
|
noagp don't initialize the AGP driver and use full aperture.
|
|
off don't use the IOMMU
|
|
leak turn on simple iommu leak tracing (only when CONFIG_IOMMU_LEAK is on)
|
|
memaper[=order] allocate an own aperture over RAM with size 32MB^order.
|
|
noforce don't force IOMMU usage. Default.
|
|
force Force IOMMU.
|
|
merge Do SG merging. Implies force (experimental)
|
|
nomerge Don't do SG merging.
|
|
forcesac For SAC mode for masks <40bits (experimental)
|
|
fullflush Flush IOMMU on each allocation (default)
|
|
nofullflush Don't use IOMMU fullflush
|
|
allowed overwrite iommu off workarounds for specific chipsets.
|
|
soft Use software bounce buffering (default for Intel machines)
|
|
noaperture Don't touch the aperture for AGP.
|
|
|
|
swiotlb=pages[,force]
|
|
|
|
pages Prereserve that many 128K pages for the software IO bounce buffering.
|
|
force Force all IO through the software TLB.
|
|
|
|
Debugging
|
|
|
|
oops=panic Always panic on oopses. Default is to just kill the process,
|
|
but there is a small probability of deadlocking the machine.
|
|
This will also cause panics on machine check exceptions.
|
|
Useful together with panic=30 to trigger a reboot.
|
|
|
|
kstack=N Print that many words from the kernel stack in oops dumps.
|
|
|
|
Misc
|
|
|
|
noreplacement Don't replace instructions with more appropiate ones
|
|
for the CPU. This may be useful on asymmetric MP systems
|
|
where some CPU have less capabilities than the others.
|