2 files changed, 23 insertions, 0 deletions

diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
index fd5a1f365c95..3cce71413d0b 100644
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -96,11 +96,15 @@
 #define MSR_IA32_MC0_ADDR               0x00000402
 #define MSR_IA32_MC0_MISC               0x00000403
 
+#define MSR_AMD64_MC0_MASK              0xc0010044
+
 #define MSR_IA32_MCx_CTL(x)             (MSR_IA32_MC0_CTL + 4*(x))
 #define MSR_IA32_MCx_STATUS(x)          (MSR_IA32_MC0_STATUS + 4*(x))
 #define MSR_IA32_MCx_ADDR(x)            (MSR_IA32_MC0_ADDR + 4*(x))
 #define MSR_IA32_MCx_MISC(x)            (MSR_IA32_MC0_MISC + 4*(x))
 
+#define MSR_AMD64_MCx_MASK(x)           (MSR_AMD64_MC0_MASK + (x))
+
 /* These are consecutive and not in the normal 4er MCE bank block */
 #define MSR_IA32_MC0_CTL2               0x00000280
 #define MSR_IA32_MCx_CTL2(x)            (MSR_IA32_MC0_CTL2 + (x))
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 3ecece0217ef..3532d3bf8105 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -615,6 +615,25 @@ static void __cpuinit init_amd(struct cpuinfo_x86 *c)
         /* As a rule processors have APIC timer running in deep C states */
         if (c->x86 >= 0xf && !cpu_has_amd_erratum(amd_erratum_400))
                 set_cpu_cap(c, X86_FEATURE_ARAT);
+
+        /*
+         * Disable GART TLB Walk Errors on Fam10h. We do this here
+         * because this is always needed when GART is enabled, even in a
+         * kernel which has no MCE support built in.
+         */
+        if (c->x86 == 0x10) {
+                /*
+                 * BIOS should disable GartTlbWlk Errors themself. If
+                 * it doesn't do it here as suggested by the BKDG.
+                 *
+                 * Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=33012
+                 */
+                u64 mask;
+
+                rdmsrl(MSR_AMD64_MCx_MASK(4), mask);
+                mask |= (1 << 10);
+                wrmsrl(MSR_AMD64_MCx_MASK(4), mask);
+        }
 }
 
 #ifdef CONFIG_X86_32