From 72b12107dafda3698e822a830eca5c8dcf3bdba3 Mon Sep 17 00:00:00 2001
From: Hugh Dickins <hughd@google.com>
Date: Wed, 19 Dec 2012 17:42:16 -0800
Subject: [PATCH] --- yaml --- r: 347346 b: refs/heads/master c:
 2832bc19f6668fd00116f61f821105040599ef8b h: refs/heads/master v: v3

---
 [refs]                    | 2 +-
 trunk/kernel/sched/fair.c | 5 ++++-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/[refs] b/[refs]
index 0f6206a9763a..84855b4ce11d 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: cda73a10eb3f493871ed39f468db50a65ebeddce
+refs/heads/master: 2832bc19f6668fd00116f61f821105040599ef8b
diff --git a/trunk/kernel/sched/fair.c b/trunk/kernel/sched/fair.c
index 4603d6cb9e25..5eea8707234a 100644
--- a/trunk/kernel/sched/fair.c
+++ b/trunk/kernel/sched/fair.c
@@ -793,8 +793,11 @@ unsigned int sysctl_numa_balancing_scan_delay = 1000;
 
 static void task_numa_placement(struct task_struct *p)
 {
-	int seq = ACCESS_ONCE(p->mm->numa_scan_seq);
+	int seq;
 
+	if (!p->mm)	/* for example, ksmd faulting in a user's mm */
+		return;
+	seq = ACCESS_ONCE(p->mm->numa_scan_seq);
 	if (p->numa_scan_seq == seq)
 		return;
 	p->numa_scan_seq = seq;