Ingo Molnar e412cd257e x86, mce: Don't initialize MCEs on unknown CPUs ... An older test-box started hanging at the following point during bootup: [ 0.022996] Mount-cache hash table entries: 512 [ 0.024996] Initializing cgroup subsys debug [ 0.025996] Initializing cgroup subsys cpuacct [ 0.026995] Initializing cgroup subsys devices [ 0.027995] Initializing cgroup subsys freezer [ 0.028995] mce: CPU supports 5 MCE banks I've bisected it down to commit 4efc0670 ("x86, mce: use 64bit machine check code on 32bit"), which utilizes the MCE code on 32-bit systems too. The problem is caused by this detail in my config: # CONFIG_CPU_SUP_INTEL is not set This disables the quirks in mce_cpu_quirks() but still enables MCE support - which then hangs due to the missing quirk workaround needed on this CPU: if (c->x86 == 6 && c->x86_model < 0x1A && banks > 0) mce_banks[0].init = 0; The safe solution is to not initialize MCEs if we dont know on what CPU we are running (or if that CPU's support code got disabled in the config). Also be a bit more defensive on 32-bit systems: dont do a boot-time dump of pending MCEs not just on the specific system that we found a problem with (Pentium-M), but earlier ones as well. Now this problem is probably not common and disabling CPU support is rare - but still being more defensive in something we turned on for a wide range of CPUs is prudent. Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> LKML-Reference: Message-ID: <4A88E3E4.40506@jp.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>		2009-08-17 13:28:25 +02:00
..
cpufreq	Remove multiple KERN_ prefixes from printk formats	2009-07-08 10:30:03 -07:00
mcheck	x86, mce: Don't initialize MCEs on unknown CPUs	2009-08-17 13:28:25 +02:00
mtrr	Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2009-06-10 15:49:36 -07:00
.gitignore
addon_cpuid_features.c	x86 ACPI: Add support for Always Running APIC timer	2009-04-07 18:17:51 -04:00
amd.c	x86: Clear incorrectly forced X86_FEATURE_LAHF_LM flag	2009-08-11 13:34:54 +02:00
bugs.c
bugs_64.c
centaur.c
cmpxchg.c
common.c	x86: Fix oops in identify_cpu() on CPUs without CPUID	2009-08-12 11:49:41 +02:00
cpu.h
cpu_debug.c	Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2009-06-10 15:51:15 -07:00
cyrix.c
hypervisor.c
intel.c	x86: add hooks for kmemcheck	2009-06-15 12:40:02 +02:00
intel_cacheinfo.c	x86: cacheinfo: complete L2/L3 Cache and TLB associativity field definitions	2009-04-10 15:41:18 +02:00
Makefile	Merge branch 'linus' into perfcounters/core-v2	2009-04-06 09:02:57 +02:00
mkcapflags.pl
perf_counter.c	perf_counter, x86: Fix/improve apic fallback	2009-08-12 14:12:49 +02:00
perfctr-watchdog.c	x86: Remove unused function lapic_watchdog_ok()	2009-07-03 14:34:31 +02:00
powerflags.c
proc.c	x86: show number of core_siblings instead of thread_siblings in /proc/cpuinfo	2009-05-04 20:36:49 +02:00
transmeta.c
umc.c
vmware.c