X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=kernel%2Fcgroup.c;h=8c6e1c17e6d37faae0870c2d9ff5635c1e192037;hb=8cde1ad6683f8738ad71f788dca8ab4810cf5afe;hp=13932abde15914e36a0d4f33e10b4a9a653f8c31;hpb=67a077dca4e648a662e32cbeaaba8094d2e30229;p=linux-2.6-omap-h63xx.git

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 13932abde15..8c6e1c17e6d 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -2735,21 +2735,24 @@ void cgroup_fork_callbacks(struct task_struct *child)
  * Called on every change to mm->owner. mm_init_owner() does not
  * invoke this routine, since it assigns the mm->owner the first time
  * and does not change it.
+ *
+ * The callbacks are invoked with mmap_sem held in read mode.
  */
 void cgroup_mm_owner_callbacks(struct task_struct *old, struct task_struct *new)
 {
-	struct cgroup *oldcgrp, *newcgrp;
+	struct cgroup *oldcgrp, *newcgrp = NULL;
 
 	if (need_mm_owner_callback) {
 		int i;
 		for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
 			struct cgroup_subsys *ss = subsys[i];
 			oldcgrp = task_cgroup(old, ss->subsys_id);
-			newcgrp = task_cgroup(new, ss->subsys_id);
+			if (new)
+				newcgrp = task_cgroup(new, ss->subsys_id);
 			if (oldcgrp == newcgrp)
 				continue;
 			if (ss->mm_owner_changed)
-				ss->mm_owner_changed(ss, oldcgrp, newcgrp);
+				ss->mm_owner_changed(ss, oldcgrp, newcgrp, new);
 		}
 	}
 }