[PATCH] x86_64: Don't run NMI watchdog during machine checks

Machine checks can stall the machine for a long time and
it's not good to trigger the nmi watchdog during that.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 7 insertions, 0 deletions

diff --git a/arch/x86_64/kernel/nmi.c b/arch/x86_64/kernel/nmi.c
index d9e4067faf05..4e6357fe0ec3 100644
--- a/arch/x86_64/kernel/nmi.c
+++ b/arch/x86_64/kernel/nmi.c
@@ -34,6 +34,7 @@
 #include <asm/proto.h>
 #include <asm/kdebug.h>
 #include <asm/local.h>
+#include <asm/mce.h>
 
 /*
  * lapic_nmi_owner tracks the ownership of the lapic NMI hardware:
@@ -480,6 +481,12 @@ void __kprobes nmi_watchdog_tick(struct pt_regs * regs, unsigned reason)
                 __get_cpu_var(nmi_touch) = 0;
                 touched = 1;
         }
+#ifdef CONFIG_X86_MCE
+        /* Could check oops_in_progress here too, but it's safer
+           not too */
+        if (atomic_read(&mce_entry) > 0)
+                touched = 1;
+#endif
         if (!touched && __get_cpu_var(last_irq_sum) == sum) {
                 /*
                  * Ayiee, looks like this CPU is stuck ...