lkml.org 
[lkml]   [2014]   [Feb]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH cgroup/for-3.14-fixes] cgroup: update cgroup_enable_task_cg_lists() to grab siglock
On 2014/2/14 2:29, Tejun Heo wrote:
> Currently, there's nothing preventing cgroup_enable_task_cg_lists()
> from missing set PF_EXITING and race against cgroup_exit(). Depending
> on the timing, cgroup_exit() may finish with the task still linked on
> css_set leading to list corruption. Fix it by grabbing siglock in
> cgroup_enable_task_cg_lists() so that PF_EXITING is guaranteed to be
> visible.
>
> This whole on-demand cg_list optimization is extremely fragile and has
> ample possibility to lead to bugs which can cause things like
> once-a-year oops during boot. I'm wondering whether the better
> approach would be just adding "cgroup_disable=all" handling which
> disables the whole cgroup rather than tempting fate with this
> on-demand craziness.
>
> Signed-off-by: Tejun Heo <tj@kernel.org>
> Cc: stable@vger.kernel.org

Acked-by: Li Zefan <lizefan@huawei.com>



\
 
 \ /
  Last update: 2014-02-15 05:21    [W:0.084 / U:0.208 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site