[SCSI] fix netlink kernel-doc

[linux-2.6-omap-h63xx.git] / kernel / cgroup.c

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 13932abde15914e36a0d4f33e10b4a9a653f8c31..8c6e1c17e6d37faae0870c2d9ff5635c1e192037 100644 (file)
--- 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);
                }
        }
 }