3 files changed, 10 insertions, 4 deletions

diff --git a/include/linux/oom.h b/include/linux/oom.h
index f209b683e118..5e3aa8311c5e 100644
--- a/include/linux/oom.h
+++ b/include/linux/oom.h
@@ -66,6 +66,8 @@ static inline void oom_killer_enable(void)
 extern unsigned long badness(struct task_struct *p, struct mem_cgroup *mem,
                       const nodemask_t *nodemask, unsigned long uptime);
 
+extern struct task_struct *find_lock_task_mm(struct task_struct *p);
+
 /* sysctls */
 extern int sysctl_oom_dump_tasks;
 extern int sysctl_oom_kill_allocating_task;
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index ea5f5edf00b7..f52b0a1861c4 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -47,6 +47,7 @@
 #include <linux/mm_inline.h>
 #include <linux/page_cgroup.h>
 #include <linux/cpu.h>
+#include <linux/oom.h>
 #include "internal.h"
 
 #include <asm/uaccess.h>
@@ -838,10 +839,13 @@ int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *mem)
 {
         int ret;
         struct mem_cgroup *curr = NULL;
+        struct task_struct *p;
 
-        task_lock(task);
-        curr = try_get_mem_cgroup_from_mm(task->mm);
-        task_unlock(task);
+        p = find_lock_task_mm(task);
+        if (!p)
+                return 0;
+        curr = try_get_mem_cgroup_from_mm(p->mm);
+        task_unlock(p);
         if (!curr)
                 return 0;
         /*
diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index d3def05a33d9..5014e50644d1 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -106,7 +106,7 @@ static void boost_dying_task_prio(struct task_struct *p,
  * pointer.  Return p, or any of its subthreads with a valid ->mm, with
  * task_lock() held.
  */
-static struct task_struct *find_lock_task_mm(struct task_struct *p)
+struct task_struct *find_lock_task_mm(struct task_struct *p)
 {
         struct task_struct *t = p;