From: Ashok Raj <ashok....@intel.com> Initialize and prepare for handling LMCEs. Add a boot-time option to disable LMCEs.
Signed-off-by: Ashok Raj <ashok....@intel.com> Cc: Tony Luck <tony.l...@intel.com> Cc: linux-edac <linux-e...@vger.kernel.org> Link: http://lkml.kernel.org/r/1433267394-10943-3-git-send-email-ashok....@intel.com [ Simplify stuff, align statements for better readability, reflow comments; kill unused lmce_clear(); save us an MSR write if LMCE is already enabled. ] Signed-off-by: Borislav Petkov <b...@suse.de> --- Documentation/x86/x86_64/boot-options.txt | 3 +++ arch/x86/include/asm/mce.h | 5 ++++ arch/x86/kernel/cpu/mcheck/mce.c | 3 +++ arch/x86/kernel/cpu/mcheck/mce_intel.c | 43 +++++++++++++++++++++++++++++++ 4 files changed, 54 insertions(+) diff --git a/Documentation/x86/x86_64/boot-options.txt b/Documentation/x86/x86_64/boot-options.txt index 5223479291a2..68ed3114c363 100644 --- a/Documentation/x86/x86_64/boot-options.txt +++ b/Documentation/x86/x86_64/boot-options.txt @@ -31,6 +31,9 @@ Machine check (e.g. BIOS or hardware monitoring applications), conflicting with OS's error handling, and you cannot deactivate the agent, then this option will be a help. + mce=no_lmce + Do not opt-in to Local MCE delivery. Use legacy method + to broadcast MCEs. mce=bootlog Enable logging of machine checks left over from booting. Disabled by default on AMD because some BIOS leave bogus ones. diff --git a/arch/x86/include/asm/mce.h b/arch/x86/include/asm/mce.h index ae2bfb895994..982dfc3679ad 100644 --- a/arch/x86/include/asm/mce.h +++ b/arch/x86/include/asm/mce.h @@ -109,6 +109,7 @@ struct mce_log { struct mca_config { bool dont_log_ce; bool cmci_disabled; + bool lmce_disabled; bool ignore_ce; bool disabled; bool ser; @@ -184,12 +185,16 @@ void cmci_clear(void); void cmci_reenable(void); void cmci_rediscover(void); void cmci_recheck(void); +void lmce_clear(void); +void lmce_enable(void); #else static inline void mce_intel_feature_init(struct cpuinfo_x86 *c) { } static inline void cmci_clear(void) {} static inline void cmci_reenable(void) {} static inline void cmci_rediscover(void) {} static inline void cmci_recheck(void) {} +static inline void lmce_clear(void) {} +static inline void lmce_enable(void) {} #endif #ifdef CONFIG_X86_MCE_AMD diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c index 0cbcd3183acf..c8c6577b4ada 100644 --- a/arch/x86/kernel/cpu/mcheck/mce.c +++ b/arch/x86/kernel/cpu/mcheck/mce.c @@ -1982,6 +1982,7 @@ void mce_disable_bank(int bank) /* * mce=off Disables machine check * mce=no_cmci Disables CMCI + * mce=no_lmce Disables LMCE * mce=dont_log_ce Clears corrected events silently, no log created for CEs. * mce=ignore_ce Disables polling and CMCI, corrected events are not cleared. * mce=TOLERANCELEVEL[,monarchtimeout] (number, see above) @@ -2005,6 +2006,8 @@ static int __init mcheck_enable(char *str) cfg->disabled = true; else if (!strcmp(str, "no_cmci")) cfg->cmci_disabled = true; + else if (!strcmp(str, "no_lmce")) + cfg->lmce_disabled = true; else if (!strcmp(str, "dont_log_ce")) cfg->dont_log_ce = true; else if (!strcmp(str, "ignore_ce")) diff --git a/arch/x86/kernel/cpu/mcheck/mce_intel.c b/arch/x86/kernel/cpu/mcheck/mce_intel.c index b4a41cf030ed..2d872deb2c50 100644 --- a/arch/x86/kernel/cpu/mcheck/mce_intel.c +++ b/arch/x86/kernel/cpu/mcheck/mce_intel.c @@ -91,6 +91,36 @@ static int cmci_supported(int *banks) return !!(cap & MCG_CMCI_P); } +static bool lmce_supported(void) +{ + u64 tmp; + + if (mca_cfg.lmce_disabled) + return false; + + rdmsrl(MSR_IA32_MCG_CAP, tmp); + + /* + * LMCE depends on recovery support in the processor. Hence both + * MCG_SER_P and MCG_LMCE_P should be present in MCG_CAP. + */ + if ((tmp & (MCG_SER_P | MCG_LMCE_P)) != + (MCG_SER_P | MCG_LMCE_P)) + return false; + + /* + * BIOS should indicate support for LMCE by setting bit 20 in + * IA32_FEATURE_CONTROL without which touching MCG_EXT_CTL will + * generate a #GP fault. + */ + rdmsrl(MSR_IA32_FEATURE_CONTROL, tmp); + if ((tmp & (FEATURE_CONTROL_LOCKED | FEATURE_CONTROL_LMCE)) == + (FEATURE_CONTROL_LOCKED | FEATURE_CONTROL_LMCE)) + return true; + + return false; +} + bool mce_intel_cmci_poll(void) { if (__this_cpu_read(cmci_storm_state) == CMCI_STORM_NONE) @@ -405,6 +435,19 @@ static void intel_init_cmci(void) cmci_recheck(); } +void intel_init_lmce(void) +{ + u64 val; + + if (!lmce_supported()) + return; + + rdmsrl(MSR_IA32_MCG_EXT_CTL, val); + + if (!(val & MCG_EXT_CTL_LMCE_EN)) + wrmsrl(MSR_IA32_MCG_EXT_CTL, val | MCG_EXT_CTL_LMCE_EN); +} + void mce_intel_feature_init(struct cpuinfo_x86 *c) { intel_init_thermal(c); -- 2.3.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
