diff options
| author | Tejun Heo <tj@kernel.org> | 2012-11-19 17:13:37 +0100 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2012-11-19 17:13:37 +0100 |
| commit | 02ae7486d05ae6df8395409a4945b2420f1e35c2 (patch) | |
| tree | 18d3f09250a850d9d6dfe3f62dfe13f4f6353374 /kernel | |
| parent | cgroup: lock cgroup_mutex in cgroup_init_subsys() (diff) | |
| download | linux-02ae7486d05ae6df8395409a4945b2420f1e35c2.tar.xz linux-02ae7486d05ae6df8395409a4945b2420f1e35c2.zip | |
cgroup: fix harmless bugs in cgroup_load_subsys() fail path and cgroup_unload_subsys()
* If idr init fails, cgroup_load_subsys() cleared dummytop->subsys[]
before calilng ->destroy() making CSS inaccessible to the callback,
and didn't unlink ss->sibling. As no modular controller uses
->use_id, this doesn't cause any actual problems.
* cgroup_unload_subsys() was forgetting to free idr, call
->pre_destroy() and clear ->active. As there currently is no
modular controller which uses ->use_id, ->pre_destroy() or ->active,
this doesn't cause any actual problems.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/cgroup.c | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 09751657abdc..5679cb1ce43f 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -4420,9 +4420,10 @@ int __init_or_module cgroup_load_subsys(struct cgroup_subsys *ss) if (ss->use_id) { int ret = cgroup_init_idr(ss, css); if (ret) { - dummytop->subsys[ss->subsys_id] = NULL; ss->destroy(dummytop); + dummytop->subsys[ss->subsys_id] = NULL; subsys[ss->subsys_id] = NULL; + list_del_init(&ss->sibling); mutex_unlock(&cgroup_mutex); return ret; } @@ -4490,7 +4491,19 @@ void cgroup_unload_subsys(struct cgroup_subsys *ss) */ BUG_ON(ss->root != &rootnode); + /* ->pre_destroy() should be called outside cgroup_mutex for now */ + if (ss->pre_destroy) + ss->pre_destroy(dummytop); + mutex_lock(&cgroup_mutex); + + ss->active = 0; + + if (ss->use_id) { + idr_remove_all(&ss->idr); + idr_destroy(&ss->idr); + } + /* deassign the subsys_id */ subsys[ss->subsys_id] = NULL; |