1 files changed, 32 insertions, 2 deletions

diff --git a/drivers/misc/sgi-xp/xpc_main.c b/drivers/misc/sgi-xp/xpc_main.c
index 8d082b46426b..d971817182f7 100644
--- a/drivers/misc/sgi-xp/xpc_main.c
+++ b/drivers/misc/sgi-xp/xpc_main.c
@@ -53,6 +53,10 @@
 #include <linux/kthread.h>
 #include "xpc.h"
 
+#ifdef CONFIG_X86_64
+#include <asm/traps.h>
+#endif
+
 /* define two XPC debug device structures to be used with dev_dbg() et al */
 
 struct device_driver xpc_dbg_name = {
@@ -1079,6 +1083,9 @@ xpc_system_reboot(struct notifier_block *nb, unsigned long event, void *unused)
         return NOTIFY_DONE;
 }
 
+/* Used to only allow one cpu to complete disconnect */
+static unsigned int xpc_die_disconnecting;
+
 /*
  * Notify other partitions to deactivate from us by first disengaging from all
  * references to our memory.
@@ -1092,6 +1099,9 @@ xpc_die_deactivate(void)
         long keep_waiting;
         long wait_to_print;
 
+        if (cmpxchg(&xpc_die_disconnecting, 0, 1))
+                return;
+
         /* keep xpc_hb_checker thread from doing anything (just in case) */
         xpc_exiting = 1;
 
@@ -1159,7 +1169,7 @@ xpc_die_deactivate(void)
  * about the lack of a heartbeat.
  */
 static int
-xpc_system_die(struct notifier_block *nb, unsigned long event, void *unused)
+xpc_system_die(struct notifier_block *nb, unsigned long event, void *_die_args)
 {
 #ifdef CONFIG_IA64              /* !!! temporary kludge */
         switch (event) {
@@ -1191,7 +1201,27 @@ xpc_system_die(struct notifier_block *nb, unsigned long event, void *unused)
                 break;
         }
 #else
-        xpc_die_deactivate();
+        struct die_args *die_args = _die_args;
+
+        switch (event) {
+        case DIE_TRAP:
+                if (die_args->trapnr == X86_TRAP_DF)
+                        xpc_die_deactivate();
+
+                if (((die_args->trapnr == X86_TRAP_MF) ||
+                     (die_args->trapnr == X86_TRAP_XF)) &&
+                    !user_mode_vm(die_args->regs))
+                        xpc_die_deactivate();
+
+                break;
+        case DIE_INT3:
+        case DIE_DEBUG:
+                break;
+        case DIE_OOPS:
+        case DIE_GPF:
+        default:
+                xpc_die_deactivate();
+        }
 #endif
 
         return NOTIFY_DONE;