4 files changed, 20 insertions, 3 deletions

diff --git a/arch/x86/kernel/kgdb.c b/arch/x86/kernel/kgdb.c
index 37194d6374d8..5d7a21119bf8 100644
--- a/arch/x86/kernel/kgdb.c
+++ b/arch/x86/kernel/kgdb.c
@@ -41,6 +41,7 @@
 #include <linux/kgdb.h>
 #include <linux/init.h>
 #include <linux/smp.h>
+#include <linux/nmi.h>
 
 #include <asm/apicdef.h>
 #include <asm/system.h>
@@ -290,6 +291,8 @@ single_step_cont(struct pt_regs *regs, struct die_args *args)
         return NOTIFY_STOP;
 }
 
+static int was_in_debug_nmi[NR_CPUS];
+
 static int __kgdb_notify(struct die_args *args, unsigned long cmd)
 {
         struct pt_regs *regs = args->regs;
@@ -299,15 +302,24 @@ static int __kgdb_notify(struct die_args *args, unsigned long cmd)
                 if (atomic_read(&kgdb_active) != -1) {
                         /* KGDB CPU roundup */
                         kgdb_nmicallback(raw_smp_processor_id(), regs);
+                        was_in_debug_nmi[raw_smp_processor_id()] = 1;
+                        touch_nmi_watchdog();
                         return NOTIFY_STOP;
                 }
                 return NOTIFY_DONE;
 
         case DIE_NMI_IPI:
                 if (atomic_read(&kgdb_active) != -1) {
-                        /* KGDB CPU roundup: */
-                        if (kgdb_nmicallback(raw_smp_processor_id(), regs))
-                                return NOTIFY_DONE;
+                        /* KGDB CPU roundup */
+                        kgdb_nmicallback(raw_smp_processor_id(), regs);
+                        was_in_debug_nmi[raw_smp_processor_id()] = 1;
+                        touch_nmi_watchdog();
+                }
+                return NOTIFY_DONE;
+
+        case DIE_NMIUNKNOWN:
+                if (was_in_debug_nmi[raw_smp_processor_id()]) {
+                        was_in_debug_nmi[raw_smp_processor_id()] = 0;
                         return NOTIFY_STOP;
                 }
                 return NOTIFY_DONE;
diff --git a/arch/x86/kernel/traps_32.c b/arch/x86/kernel/traps_32.c
index b22c01e05a18..c5421f30d678 100644
--- a/arch/x86/kernel/traps_32.c
+++ b/arch/x86/kernel/traps_32.c
@@ -708,6 +708,8 @@ io_check_error(unsigned char reason, struct pt_regs * regs)
 static __kprobes void
 unknown_nmi_error(unsigned char reason, struct pt_regs * regs)
 {
+        if (notify_die(DIE_NMIUNKNOWN, "nmi", regs, reason, 2, SIGINT) == NOTIFY_STOP)
+                return;
 #ifdef CONFIG_MCA
         /* Might actually be able to figure out what the guilty party
         * is. */
diff --git a/arch/x86/kernel/traps_64.c b/arch/x86/kernel/traps_64.c
index 045466681911..055b1650c69d 100644
--- a/arch/x86/kernel/traps_64.c
+++ b/arch/x86/kernel/traps_64.c
@@ -806,6 +806,8 @@ io_check_error(unsigned char reason, struct pt_regs * regs)
 static __kprobes void
 unknown_nmi_error(unsigned char reason, struct pt_regs * regs)
 {
+        if (notify_die(DIE_NMIUNKNOWN, "nmi", regs, reason, 2, SIGINT) == NOTIFY_STOP)
+                return;
         printk(KERN_EMERG "Uhhuh. NMI received for unknown reason %02x.\n",
                 reason);
         printk(KERN_EMERG "Do you have a strange power saving mode enabled?\n");
diff --git a/include/asm-x86/kdebug.h b/include/asm-x86/kdebug.h
index 99dcbafa1511..35231240ebdc 100644
--- a/include/asm-x86/kdebug.h
+++ b/include/asm-x86/kdebug.h
@@ -20,6 +20,7 @@ enum die_val {
         DIE_CALL,
         DIE_NMI_IPI,
         DIE_PAGE_FAULT,
+        DIE_NMIUNKNOWN,
 };
 
 extern void printk_address(unsigned long address, int reliable);