From 6aded17f7f47cb4ee10776c54372841b21170ae4 Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Mon, 18 May 2015 10:07:17 +0200 Subject: x86/mce: Fix MCE severity messages [ Upstream commit 17fea54bf0ab34fa09a06bbde2f58ed7bbdf9299 ] Derek noticed that a critical MCE gets reported with the wrong error type description: [Hardware Error]: CPU 34: Machine Check Exception: 5 Bank 9: f200003f000100b0 [Hardware Error]: RIP !INEXACT! 10: {intel_idle+0xb1/0x170} [Hardware Error]: TSC 49587b8e321cb [Hardware Error]: PROCESSOR 0:306e4 TIME 1431561296 SOCKET 1 APIC 29 [Hardware Error]: Some CPUs didn't answer in synchronization [Hardware Error]: Machine check: Invalid ^^^^^^^ The last line with 'Invalid' should have printed the high level MCE error type description we get from mce_severity, i.e. something like: [Hardware Error]: Machine check: Action required: data load error in a user process this happens due to the fact that mce_no_way_out() iterates over all MCA banks and possibly overwrites the @msg argument which is used in the panic printing later. Change behavior to take the message of only and the (last) critical MCE it detects. Reported-by: Derek Signed-off-by: Borislav Petkov Cc: Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Tony Luck Link: http://lkml.kernel.org/r/1431936437-25286-3-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin --- arch/x86/kernel/cpu/mcheck/mce.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'arch/x86') diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c index 453e9bf90968..b5c2276317e2 100644 --- a/arch/x86/kernel/cpu/mcheck/mce.c +++ b/arch/x86/kernel/cpu/mcheck/mce.c @@ -660,6 +660,7 @@ static int mce_no_way_out(struct mce *m, char **msg, unsigned long *validp, struct pt_regs *regs) { int i, ret = 0; + char *tmp; for (i = 0; i < mca_cfg.banks; i++) { m->status = mce_rdmsrl(MSR_IA32_MCx_STATUS(i)); @@ -668,9 +669,11 @@ static int mce_no_way_out(struct mce *m, char **msg, unsigned long *validp, if (quirk_no_way_out) quirk_no_way_out(i, m, regs); } - if (mce_severity(m, mca_cfg.tolerant, msg, true) >= - MCE_PANIC_SEVERITY) + + if (mce_severity(m, mca_cfg.tolerant, &tmp, true) >= MCE_PANIC_SEVERITY) { + *msg = tmp; ret = 1; + } } return ret; } -- cgit v1.2.3