1 files changed, 33 insertions, 15 deletions

diff --git a/arch/x86/kernel/cpu/perf_event_p6.c b/arch/x86/kernel/cpu/perf_event_p6.c
index b1e2fe115323..7c1a0c07b607 100644
--- a/arch/x86/kernel/cpu/perf_event_p6.c
+++ b/arch/x86/kernel/cpu/perf_event_p6.c
@@ -231,31 +231,49 @@ static __initconst const struct x86_pmu p6_pmu = {
 
 };
 
+static __init void p6_pmu_rdpmc_quirk(void)
+{
+        if (boot_cpu_data.x86_mask < 9) {
+                /*
+                 * PPro erratum 26; fixed in stepping 9 and above.
+                 */
+                pr_warn("Userspace RDPMC support disabled due to a CPU erratum\n");
+                x86_pmu.attr_rdpmc_broken = 1;
+                x86_pmu.attr_rdpmc = 0;
+        }
+}
+
 __init int p6_pmu_init(void)
 {
+        x86_pmu = p6_pmu;
+
         switch (boot_cpu_data.x86_model) {
-        case 1:
-        case 3:  /* Pentium Pro */
-        case 5:
-        case 6:  /* Pentium II */
-        case 7:
-        case 8:
-        case 11: /* Pentium III */
-        case 9:
-        case 13:
-                /* Pentium M */
+        case  1: /* Pentium Pro */
+                x86_add_quirk(p6_pmu_rdpmc_quirk);
+                break;
+
+        case  3: /* Pentium II - Klamath */
+        case  5: /* Pentium II - Deschutes */
+        case  6: /* Pentium II - Mendocino */
                 break;
+
+        case  7: /* Pentium III - Katmai */
+        case  8: /* Pentium III - Coppermine */
+        case 10: /* Pentium III Xeon */
+        case 11: /* Pentium III - Tualatin */
+                break;
+
+        case  9: /* Pentium M - Banias */
+        case 13: /* Pentium M - Dothan */
+                break;
+
         default:
-                pr_cont("unsupported p6 CPU model %d ",
-                        boot_cpu_data.x86_model);
+                pr_cont("unsupported p6 CPU model %d ", boot_cpu_data.x86_model);
                 return -ENODEV;
         }
 
-        x86_pmu = p6_pmu;
-
         memcpy(hw_cache_event_ids, p6_hw_cache_event_ids,
                 sizeof(hw_cache_event_ids));
 
-
         return 0;
 }