Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fix from Thomas Gleixner:
 "A single fix for an AMD erratum so machines without a BIOS fix work"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/AMD: Apply erratum 665 on machines without a BIOS fix

1 files changed, 12 insertions, 0 deletions

diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index f5c69d8974e1..b81fe2d63e15 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -669,6 +669,17 @@ static void init_amd_gh(struct cpuinfo_x86 *c)
                 set_cpu_bug(c, X86_BUG_AMD_TLB_MMATCH);
 }
 
+#define MSR_AMD64_DE_CFG        0xC0011029
+
+static void init_amd_ln(struct cpuinfo_x86 *c)
+{
+        /*
+         * Apply erratum 665 fix unconditionally so machines without a BIOS
+         * fix work.
+         */
+        msr_set_bit(MSR_AMD64_DE_CFG, 31);
+}
+
 static void init_amd_bd(struct cpuinfo_x86 *c)
 {
         u64 value;
@@ -726,6 +737,7 @@ static void init_amd(struct cpuinfo_x86 *c)
         case 6:    init_amd_k7(c); break;
         case 0xf:  init_amd_k8(c); break;
         case 0x10: init_amd_gh(c); break;
+        case 0x12: init_amd_ln(c); break;
         case 0x15: init_amd_bd(c); break;
         }