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.
+ Disabled by default on AMD 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.
+ in a reboot. On Intel systems it is enabled by default.
+ mce=nobootlog
+ Disable boot machine check logging.
+ mce=tolerancelevel (number)
+ 0: always panic, 1: panic if deadlock possible,
+ 2: try to avoid panic, 3: never panic or exit (for testing)
+ default is 1
+ Can be also set using sysfs which is preferable.
nomce (for compatibility with i386): same as mce=off
no_timer_check Don't check the IO-APIC timer. This can work around
problems with incorrect timer initialization on some boards.
+ apicmaintimer Run time keeping from the local APIC timer instead
+ of using the PIT/HPET interrupt for this. This is useful
+ when the PIT/HPET interrupts are unreliable.
+
+ noapicmaintimer Don't do time keeping using the APIC timer.
+ Useful when this option was auto selected, but doesn't work.
+
+ apicpmtimer
+ Do APIC timer calibration using the pmtimer. Implies
+ apicmaintimer. Useful when your PIT timer is totally
+ broken.
+
+ disable_8254_timer / enable_8254_timer
+ Enable interrupt 0 timer routing over the 8254 in addition to over
+ the IO-APIC. The kernel tries to set a sensible default.
+
Early Console
syntax: earlyprintk=vga
cpumask=MASK only use cpus with bits set in mask
+ additional_cpus=NUM Allow NUM more CPUs for hotplug
+ (defaults are specified by the BIOS, see Documentation/x86_64/cpu-hotplug-spec)
+
NUMA
numa=off Only set up a single NUMA node spanning all memory.
numa=fake=X Fake X nodes and ignore NUMA setup of the actual machine.
+ numa=hotadd=percent
+ Only allow hotadd memory to preallocate page structures upto
+ percent of already available memory.
+ numa=hotadd=0 will disable hotadd memory.
+
ACPI
acpi=off Don't enable ACPI
pages Prereserve that many 128K pages for the software IO bounce buffering.
force Force all IO through the software TLB.
+ calgary=[64k,128k,256k,512k,1M,2M,4M,8M]
+ calgary=[translate_empty_slots]
+ calgary=[disable=<PCI bus number>]
+
+ 64k,...,8M - Set the size of each PCI slot's translation table
+ when using the Calgary IOMMU. This is the size of the translation
+ table itself in main memory. The smallest table, 64k, covers an IO
+ space of 32MB; the largest, 8MB table, can cover an IO space of
+ 4GB. Normally the kernel will make the right choice by itself.
+
+ translate_empty_slots - Enable translation even on slots that have
+ no devices attached to them, in case a device will be hotplugged
+ in the future.
+
+ disable=<PCI bus number> - Disable translation on a given PHB. For
+ example, the built-in graphics adapter resides on the first bridge
+ (PCI bus number 0); if translation (isolation) is enabled on this
+ bridge, X servers that access the hardware directly from user
+ space might stop working. Use this option if you have devices that
+ are accessed from userspace directly on some PCI host bridge.
+
Debugging
oops=panic Always panic on oopses. Default is to just kill the process,
kstack=N Print that many words from the kernel stack in oops dumps.
+ pagefaulttrace Dump all page faults. Only useful for extreme debugging
+ and will create a lot of output.
+
+ call_trace=[old|both|newfallback|new]
+ old: use old inexact backtracer
+ new: use new exact dwarf2 unwinder
+ both: print entries from both
+ newfallback: use new unwinder but fall back to old if it gets
+ stuck (default)
+
Misc
- noreplacement Don't replace instructions with more appropiate ones
+ noreplacement Don't replace instructions with more appropriate ones
for the CPU. This may be useful on asymmetric MP systems
where some CPU have less capabilities than the others.
git.openpandora.org / pandora-kernel.git / blobdiff