5 files changed, 56 insertions, 1 deletions

diff --git a/arch/x86/include/asm/mce.h b/arch/x86/include/asm/mce.h
index 38d3a1a8830f..2dbc0bf2b9f3 100644
--- a/arch/x86/include/asm/mce.h
+++ b/arch/x86/include/asm/mce.h
@@ -151,10 +151,12 @@ extern int mce_p5_enabled;
 #ifdef CONFIG_X86_MCE
 int mcheck_init(void);
 void mcheck_cpu_init(struct cpuinfo_x86 *c);
+void mcheck_cpu_clear(struct cpuinfo_x86 *c);
 void mcheck_vendor_init_severity(void);
 #else
 static inline int mcheck_init(void) { return 0; }
 static inline void mcheck_cpu_init(struct cpuinfo_x86 *c) {}
+static inline void mcheck_cpu_clear(struct cpuinfo_x86 *c) {}
 static inline void mcheck_vendor_init_severity(void) {}
 #endif
 
@@ -181,12 +183,14 @@ DECLARE_PER_CPU(struct device *, mce_device);
 
 #ifdef CONFIG_X86_MCE_INTEL
 void mce_intel_feature_init(struct cpuinfo_x86 *c);
+void mce_intel_feature_clear(struct cpuinfo_x86 *c);
 void cmci_clear(void);
 void cmci_reenable(void);
 void cmci_rediscover(void);
 void cmci_recheck(void);
 #else
 static inline void mce_intel_feature_init(struct cpuinfo_x86 *c) { }
+static inline void mce_intel_feature_clear(struct cpuinfo_x86 *c) { }
 static inline void cmci_clear(void) {}
 static inline void cmci_reenable(void) {}
 static inline void cmci_rediscover(void) {}
diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index 32b586ee006a..ee5272d77a16 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -1606,6 +1606,17 @@ static void __mcheck_cpu_init_vendor(struct cpuinfo_x86 *c)
         }
 }
 
+static void __mcheck_cpu_clear_vendor(struct cpuinfo_x86 *c)
+{
+        switch (c->x86_vendor) {
+        case X86_VENDOR_INTEL:
+                mce_intel_feature_clear(c);
+                break;
+        default:
+                break;
+        }
+}
+
 static void mce_start_timer(unsigned int cpu, struct timer_list *t)
 {
         unsigned long iv = check_interval * HZ;
@@ -1673,6 +1684,25 @@ void mcheck_cpu_init(struct cpuinfo_x86 *c)
 }
 
 /*
+ * Called for each booted CPU to clear some machine checks opt-ins
+ */
+void mcheck_cpu_clear(struct cpuinfo_x86 *c)
+{
+        if (mca_cfg.disabled)
+                return;
+
+        if (!mce_available(c))
+                return;
+
+        /*
+         * Possibly to clear general settings generic to x86
+         * __mcheck_cpu_clear_generic(c);
+         */
+        __mcheck_cpu_clear_vendor(c);
+
+}
+
+/*
  * mce_chrdev: Character device /dev/mcelog to read and clear the MCE log.
  */
 
diff --git a/arch/x86/kernel/cpu/mcheck/mce_intel.c b/arch/x86/kernel/cpu/mcheck/mce_intel.c
index 70f567f774ed..c5c003291861 100644
--- a/arch/x86/kernel/cpu/mcheck/mce_intel.c
+++ b/arch/x86/kernel/cpu/mcheck/mce_intel.c
@@ -434,7 +434,7 @@ static void intel_init_cmci(void)
         cmci_recheck();
 }
 
-void intel_init_lmce(void)
+static void intel_init_lmce(void)
 {
         u64 val;
 
@@ -447,9 +447,26 @@ void intel_init_lmce(void)
                 wrmsrl(MSR_IA32_MCG_EXT_CTL, val | MCG_EXT_CTL_LMCE_EN);
 }
 
+static void intel_clear_lmce(void)
+{
+        u64 val;
+
+        if (!lmce_supported())
+                return;
+
+        rdmsrl(MSR_IA32_MCG_EXT_CTL, val);
+        val &= ~MCG_EXT_CTL_LMCE_EN;
+        wrmsrl(MSR_IA32_MCG_EXT_CTL, val);
+}
+
 void mce_intel_feature_init(struct cpuinfo_x86 *c)
 {
         intel_init_thermal(c);
         intel_init_cmci();
         intel_init_lmce();
 }
+
+void mce_intel_feature_clear(struct cpuinfo_x86 *c)
+{
+        intel_clear_lmce();
+}
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 397688beed4b..b20ef187ff41 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -29,6 +29,7 @@
 #include <asm/debugreg.h>
 #include <asm/nmi.h>
 #include <asm/tlbflush.h>
+#include <asm/mce.h>
 
 /*
  * per-CPU TSS segments. Threads are completely 'soft' on Linux,
@@ -319,6 +320,7 @@ void stop_this_cpu(void *dummy)
          */
         set_cpu_online(smp_processor_id(), false);
         disable_local_APIC();
+        mcheck_cpu_clear(this_cpu_ptr(&cpu_info));
 
         for (;;)
                 halt();
diff --git a/arch/x86/kernel/smp.c b/arch/x86/kernel/smp.c
index 15aaa69bbb5e..12c8286206ce 100644
--- a/arch/x86/kernel/smp.c
+++ b/arch/x86/kernel/smp.c
@@ -30,6 +30,7 @@
 #include <asm/proto.h>
 #include <asm/apic.h>
 #include <asm/nmi.h>
+#include <asm/mce.h>
 #include <asm/trace/irq_vectors.h>
 /*
  *      Some notes on x86 processor bugs affecting SMP operation:
@@ -243,6 +244,7 @@ static void native_stop_other_cpus(int wait)
 finish:
         local_irq_save(flags);
         disable_local_APIC();
+        mcheck_cpu_clear(this_cpu_ptr(&cpu_info));
         local_irq_restore(flags);
 }