Merge tag 'ras-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull RAS fixes from Thomas Gleixner:
 "Two RAS related fixes:

   - Shut down the per CPU thermal throttling poll work properly when a
     CPU goes offline.

     The missing shutdown caused the poll work to be migrated to a
     unbound worker which triggered warnings about the usage of
     smp_processor_id() in preemptible context

   - Fix the PPIN feature initialization which missed to enable the
     functionality when PPIN_CTL was enabled but the MSR locked against
     updates"

* tag 'ras-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce: Fix logic and comments around MSR_PPIN_CTL
  x86/mce/therm_throt: Undo thermal polling properly on CPU offline

Author: torvalds

arch/x86/kernel/cpu/mce/intel.c

@@ -493,17 +493,18 @@ static void intel_ppin_init(struct cpuinfo_x86 *c)
 			return;
 
 		if ((val & 3UL) == 1UL) {
-			/* PPIN available but disabled: */
+			/* PPIN locked in disabled mode */
 			return;
 		}
 
-		/* If PPIN is disabled, but not locked, try to enable: */
-		if (!(val & 3UL)) {
+		/* If PPIN is disabled, try to enable */
+		if (!(val & 2UL)) {
 			wrmsrl_safe(MSR_PPIN_CTL,  val | 2UL);
 			rdmsrl_safe(MSR_PPIN_CTL, &val);
 		}
 
-		if ((val & 3UL) == 2UL)
+		/* Is the enable bit set? */
+		if (val & 2UL)
 			set_cpu_cap(c, X86_FEATURE_INTEL_PPIN);
 	}
 }

arch/x86/kernel/cpu/mce/therm_throt.c

@@ -486,9 +486,14 @@ static int thermal_throttle_offline(unsigned int cpu)
 {
 	struct thermal_state *state = &per_cpu(thermal_state, cpu);
 	struct device *dev = get_cpu_device(cpu);
+	u32 l;
+
+	/* Mask the thermal vector before draining evtl. pending work */
+	l = apic_read(APIC_LVTTHMR);
+	apic_write(APIC_LVTTHMR, l | APIC_LVT_MASKED);
 
-	cancel_delayed_work(&state->package_throttle.therm_work);
-	cancel_delayed_work(&state->core_throttle.therm_work);
+	cancel_delayed_work_sync(&state->package_throttle.therm_work);
+	cancel_delayed_work_sync(&state->core_throttle.therm_work);
 
 	state->package_throttle.rate_control_active = false;
 	state->core_throttle.rate_control_active = false;