diff options
| author | Li Zefan <lizf@cn.fujitsu.com> | 2010-04-22 17:30:00 +0800 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2010-05-04 09:25:00 -0700 |
| commit | fae9c791703606636c1220e47f6690660042ce7f (patch) | |
| tree | c4d1bf20f4b73ee438ae2c3168b9b7ead1418215 | |
| parent | 9a9686b634acc5cb6b7c601c171ae64af0318a24 (diff) | |
| download | linux-fae9c791703606636c1220e47f6690660042ce7f.tar.bz2 | |
cgroup: Fix an RCU warning in alloc_css_id()
With CONFIG_PROVE_RCU=y, a warning can be triggered:
# mount -t cgroup -o memory xxx /mnt
# mkdir /mnt/0
...
kernel/cgroup.c:4442 invoked rcu_dereference_check() without protection!
...
This is a false-positive. It's safe to directly access parent_css->id.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
| -rw-r--r-- | kernel/cgroup.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 4ca928db890c..3a53c771e503 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -4561,13 +4561,13 @@ static int alloc_css_id(struct cgroup_subsys *ss, struct cgroup *parent, { int subsys_id, i, depth = 0; struct cgroup_subsys_state *parent_css, *child_css; - struct css_id *child_id, *parent_id = NULL; + struct css_id *child_id, *parent_id; subsys_id = ss->subsys_id; parent_css = parent->subsys[subsys_id]; child_css = child->subsys[subsys_id]; - depth = css_depth(parent_css) + 1; parent_id = parent_css->id; + depth = parent_id->depth; child_id = get_new_cssid(ss, depth); if (IS_ERR(child_id)) |