From 3403189a98fbb04357d7ec080d8c5f2350163fa7 Mon Sep 17 00:00:00 2001
From: Robin Holt <holt@sgi.com>
Date: Thu, 20 Dec 2012 15:05:50 -0800
Subject: [PATCH] --- yaml --- r: 347889 b: refs/heads/master c:
 891348ca0f66206f1dc0e30d63757e3df1ae2d15 h: refs/heads/master i:   347887:
 7e1a77266f080e719b60a5071773340b7784a3c1 v: v3

---
 [refs]                               |  2 +-
 trunk/drivers/misc/sgi-xp/xpc_main.c | 34 ++++++++++++++++++++++++++--
 2 files changed, 33 insertions(+), 3 deletions(-)

diff --git a/[refs] b/[refs]
index 227af49fe776..80d031fcb495 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: c39540c6d1add1d0ad843b3d2437311924193359
+refs/heads/master: 891348ca0f66206f1dc0e30d63757e3df1ae2d15
diff --git a/trunk/drivers/misc/sgi-xp/xpc_main.c b/trunk/drivers/misc/sgi-xp/xpc_main.c
index 8d082b46426b..d971817182f7 100644
--- a/trunk/drivers/misc/sgi-xp/xpc_main.c
+++ b/trunk/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;