[Devel] [PATCH cgroup/for-3.13-fixes] cgroup: fix oops in cgroup init failure path

[Vladimir Davydov]

On 12/06/2013 08:13 PM, Tejun Heo wrote:
> Hello, Vladimir.
>
> On Fri, Dec 06, 2013 at 11:02:07AM +0400, Vladimir Davydov wrote:
>> This patch fixes this bug, but I have a couple of questions regarding it.
>>
>> First, cgroup_load_subsys() also calls css_online(), and if it fails, it
>> calls cgroup_unload_subsys() to rollback. The latter function executes
>> the following command:
>>
>>     offline_css(cgroup_css(cgroup_dummy_top, ss));
>>
>> But since we failed to online_css(), cgroup_css() will return NULL
>> resulting in another oops.
> I don't think the root css onlining fails for any existing controllers
> but yeah that looks wrong.  Can you please send a patch?

Sure, I will send it soon.

Thanks.