On 04/19/2012 07:53 PM, Tejun Heo wrote:
On Thu, Apr 19, 2012 at 07:49:16PM -0300, Glauber Costa wrote:Not all external callers of cgroup_attach_task() test to see if the cgroup is still live - the internal callers at cgroup.c does. With this test in cgroup_attach_task, we can assure that no tasks are ever moved to a cgroup that is past its destruction point and was already marked as dead. Signed-off-by: Glauber Costa<glommer@xxxxxxxxxxxxx> CC: Tejun Heo<tj@xxxxxxxxxx> CC: Li Zefan<lizefan@xxxxxxxxxx> CC: Kamezawa Hiroyuki<kamezawa.hiroyu@xxxxxxxxxxxxxx> --- kernel/cgroup.c | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-) diff --git a/kernel/cgroup.c b/kernel/cgroup.c index b61b938..932c318 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -1927,6 +1927,9 @@ int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk) struct cgroup_taskset tset = { }; struct css_set *newcg; + if (cgroup_is_removed(cgrp)) + return -ENODEV; +Isn't the test in cgroup_lock_live_group() enough?
Yes, when it is done. Not all callers take it, specially the external ones. -- To unsubscribe from this list: send the line "unsubscribe cgroups" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
