From 32544f060326bffa60dade49ce4595652df4d3ab Mon Sep 17 00:00:00 2001 From: Yazen Ghannam Date: Wed, 11 May 2016 14:58:24 +0200 Subject: [PATCH] x86/mce/AMD: Disable LogDeferredInMcaStat for SMCA systems Disable Deferred Error logging in MCA_{STATUS,ADDR} additionally for SMCA systems as this information will retrieved from MCA_DE{STAT,ADDR} on those systems. Signed-off-by: Yazen Ghannam [ Simplify, drop SMCA_MCAX_EN_OFF define too. ] Signed-off-by: Borislav Petkov Cc: Andy Lutomirski Cc: Aravind Gopalakrishnan Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Tony Luck Cc: linux-edac Link: http://lkml.kernel.org/r/1462971509-3856-3-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/mcheck/mce_amd.c | 38 +++++++++++++++++++++++++++--------- 1 file changed, 29 insertions(+), 9 deletions(-) diff --git a/arch/x86/kernel/cpu/mcheck/mce_amd.c b/arch/x86/kernel/cpu/mcheck/mce_amd.c index d1b1e62..527ddae 100644 --- a/arch/x86/kernel/cpu/mcheck/mce_amd.c +++ b/arch/x86/kernel/cpu/mcheck/mce_amd.c @@ -54,14 +54,6 @@ /* Threshold LVT offset is at MSR0xC0000410[15:12] */ #define SMCA_THR_LVT_OFF 0xF000 -/* - * OS is required to set the MCAX bit to acknowledge that it is now using the - * new MSR ranges and new registers under each bank. It also means that the OS - * will configure deferred errors in the new MCx_CONFIG register. If the bit is - * not set, uncorrectable errors will cause a system panic. - */ -#define SMCA_MCAX_EN_OFF 0x1 - static const char * const th_names[] = { "load_store", "insn_fetch", @@ -374,7 +366,35 @@ prepare_threshold_block(unsigned int bank, unsigned int block, u32 addr, u32 smca_addr = MSR_AMD64_SMCA_MCx_CONFIG(bank); if (!rdmsr_safe(smca_addr, &smca_low, &smca_high)) { - smca_high |= SMCA_MCAX_EN_OFF; + /* + * OS is required to set the MCAX bit to acknowledge + * that it is now using the new MSR ranges and new + * registers under each bank. It also means that the OS + * will configure deferred errors in the new MCx_CONFIG + * register. If the bit is not set, uncorrectable errors + * will cause a system panic. + * + * MCA_CONFIG[MCAX] is bit 32 (0 in the high portion of + * the MSR.) + */ + smca_high |= BIT(0); + + /* + * SMCA logs Deferred Error information in + * MCA_DE{STAT,ADDR} registers with the option of + * additionally logging to MCA_{STATUS,ADDR} if + * MCA_CONFIG[LogDeferredInMcaStat] is set. + * + * This bit is usually set by BIOS to retain the old + * behavior for OSes that don't use the new registers. + * Linux supports the new registers so let's disable + * that additional logging here. + * + * MCA_CONFIG[LogDeferredInMcaStat] is bit 34 (bit 2 in + * the high portion of the MSR). + */ + smca_high &= ~BIT(2); + wrmsr(smca_addr, smca_low, smca_high); } -- 2.7.4