Merge branch 'linus' into perf/core

Merge reason: Pick up upstream fixes.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 19 insertions, 0 deletions

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