From: Tony Luck Date: Fri, 25 May 2018 21:41:39 +0000 (-0700) Subject: x86/mce: Improve error message when kernel cannot recover X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=c7d606f560e4c698884697fef503e4abacdd8c25;p=linux.git x86/mce: Improve error message when kernel cannot recover Since we added support to add recovery from some errors inside the kernel in: commit b2f9d678e28c ("x86/mce: Check for faults tagged in EXTABLE_CLASS_FAULT exception table entries") we have done a less than stellar job at reporting the cause of recoverable machine checks that occur in other parts of the kernel. The user just gets the unhelpful message: mce: [Hardware Error]: Machine check: Action required: unknown MCACOD doubly unhelpful when they check the manual for the reported IA32_MSR_STATUS.MCACOD and see that it is listed as one of the standard recoverable values. Add an extra rule to the MCE severity table to catch this case and report it as: mce: [Hardware Error]: Machine check: Data load in unrecoverable area of kernel Fixes: b2f9d678e28c ("x86/mce: Check for faults tagged in EXTABLE_CLASS_FAULT exception table entries") Signed-off-by: Tony Luck Signed-off-by: Thomas Gleixner Cc: Qiuxu Zhuo Cc: Ashok Raj Cc: stable@vger.kernel.org # 4.6+ Cc: Dan Williams Cc: Borislav Petkov Link: https://lkml.kernel.org/r/4cc7c465150a9a48b8b9f45d0b840278e77eb9b5.1527283897.git.tony.luck@intel.com --- diff --git a/arch/x86/kernel/cpu/mcheck/mce-severity.c b/arch/x86/kernel/cpu/mcheck/mce-severity.c index 5bbd06f38ff68..f34d89c01edc5 100644 --- a/arch/x86/kernel/cpu/mcheck/mce-severity.c +++ b/arch/x86/kernel/cpu/mcheck/mce-severity.c @@ -160,6 +160,11 @@ static struct severity { SER, MASK(MCI_STATUS_OVER|MCI_UC_SAR|MCI_ADDR|MCACOD, MCI_UC_SAR|MCI_ADDR|MCACOD_INSTR), USER ), + MCESEV( + PANIC, "Data load in unrecoverable area of kernel", + SER, MASK(MCI_STATUS_OVER|MCI_UC_SAR|MCI_ADDR|MCACOD, MCI_UC_SAR|MCI_ADDR|MCACOD_DATA), + KERNEL + ), #endif MCESEV( PANIC, "Action required: unknown MCACOD",