From 45d4b7b9cb88526f6d5bd4c03efab88d75d10e4f Mon Sep 17 00:00:00 2001 From: Yazen Ghannam Date: Mon, 25 Mar 2019 16:34:22 +0000 Subject: [PATCH] x86/MCE: Add an MCE-record filtering function Some systems may report spurious MCA errors. In general, spurious MCA errors may be disabled by clearing a particular bit in MCA_CTL. However, clearing a bit in MCA_CTL may not be recommended for some errors, so the only option is to ignore them. An MCA error is printed and handled after it has been added to the MCE event pool. So an MCA error can be ignored by not adding it to that pool in the first place. Add such a filtering function. [ bp: Move function prototype to the internal header and massage. ] Signed-off-by: Yazen Ghannam Signed-off-by: Borislav Petkov Cc: Arnd Bergmann Cc: "clemej@gmail.com" Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: Pu Wen Cc: Qiuxu Zhuo Cc: "rafal@milecki.pl" Cc: Shirish S Cc: # 5.0.x Cc: Thomas Gleixner Cc: Tony Luck Cc: Vishal Verma Cc: x86-ml Link: https://lkml.kernel.org/r/20190325163410.171021-1-Yazen.Ghannam@amd.com --- arch/x86/kernel/cpu/mce/core.c | 5 +++++ arch/x86/kernel/cpu/mce/genpool.c | 3 +++ arch/x86/kernel/cpu/mce/internal.h | 3 +++ 3 files changed, 11 insertions(+) diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c index 3e08142..80b8c6bf 100644 --- a/arch/x86/kernel/cpu/mce/core.c +++ b/arch/x86/kernel/cpu/mce/core.c @@ -1775,6 +1775,11 @@ static void __mcheck_cpu_init_timer(void) mce_start_timer(t); } +bool filter_mce(struct mce *m) +{ + return false; +} + /* Handle unconfigured int18 (should never happen) */ static void unexpected_machine_check(struct pt_regs *regs, long error_code) { diff --git a/arch/x86/kernel/cpu/mce/genpool.c b/arch/x86/kernel/cpu/mce/genpool.c index 3395549..64d1d5a 100644 --- a/arch/x86/kernel/cpu/mce/genpool.c +++ b/arch/x86/kernel/cpu/mce/genpool.c @@ -99,6 +99,9 @@ int mce_gen_pool_add(struct mce *mce) { struct mce_evt_llist *node; + if (filter_mce(mce)) + return -EINVAL; + if (!mce_evt_pool) return -EINVAL; diff --git a/arch/x86/kernel/cpu/mce/internal.h b/arch/x86/kernel/cpu/mce/internal.h index af5eab1..b822a64 100644 --- a/arch/x86/kernel/cpu/mce/internal.h +++ b/arch/x86/kernel/cpu/mce/internal.h @@ -173,4 +173,7 @@ struct mca_msr_regs { extern struct mca_msr_regs msr_ops; +/* Decide whether to add MCE record to MCE event pool or filter it out. */ +extern bool filter_mce(struct mce *m); + #endif /* __X86_MCE_INTERNAL_H__ */ -- 2.7.4