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

Pull RAS fix from Borislav Petkov:
 "One urgent fix for the thermal throttling machinery: the recent change
  reworking the thermal notifications forgot to mask out read-only and
  reserved bits in the thermal status MSRs, leading to exceptions while
  writing those MSRs.

  The fix takes care of masking out those bits first"

* 'ras-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce/therm_throt: Mask out read-only and reserved MSR bits

diff --git a/arch/x86/kernel/cpu/mce/therm_throt.c b/arch/x86/kernel/cpu/mce/therm_throt.c
index d01e0da..b38010b 100644 (file)
--- a/arch/x86/kernel/cpu/mce/therm_throt.c
+++ b/arch/x86/kernel/cpu/mce/therm_throt.c
@@ -195,17 +195,24 @@ static const struct attribute_group thermal_attr_group = {
 #define THERM_THROT_POLL_INTERVAL      HZ
 #define THERM_STATUS_PROCHOT_LOG       BIT(1)
 
+#define THERM_STATUS_CLEAR_CORE_MASK (BIT(1) | BIT(3) | BIT(5) | BIT(7) | BIT(9) | BIT(11) | BIT(13) | BIT(15))
+#define THERM_STATUS_CLEAR_PKG_MASK  (BIT(1) | BIT(3) | BIT(5) | BIT(7) | BIT(9) | BIT(11))
+
 static void clear_therm_status_log(int level)
 {
        int msr;
-       u64 msr_val;
+       u64 mask, msr_val;
 
-       if (level == CORE_LEVEL)
-               msr = MSR_IA32_THERM_STATUS;
-       else
-               msr = MSR_IA32_PACKAGE_THERM_STATUS;
+       if (level == CORE_LEVEL) {
+               msr  = MSR_IA32_THERM_STATUS;
+               mask = THERM_STATUS_CLEAR_CORE_MASK;
+       } else {
+               msr  = MSR_IA32_PACKAGE_THERM_STATUS;
+               mask = THERM_STATUS_CLEAR_PKG_MASK;
+       }
 
        rdmsrl(msr, msr_val);
+       msr_val &= mask;
        wrmsrl(msr, msr_val & ~THERM_STATUS_PROCHOT_LOG);
 }