Messages in this thread | | | Subject | Re: [PATCH] sched, cgroup: Use exit hook to avoid use-after-free crash | From | Mike Galbraith <> | Date | Fri, 24 Dec 2010 18:24:51 +0100 |
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On Fri, 2010-12-24 at 18:07 +0100, Peter Zijlstra wrote: > On Fri, 2010-12-24 at 17:48 +0100, Mike Galbraith wrote: > > On Fri, 2010-12-24 at 16:59 +0100, Peter Zijlstra wrote: > > > > > So cgroup moves a task without calling cgroup_subsys::attach() which is > > > odd, but it does have an ::exit method, sadly it calls that _before_ > > > re-assigning the task, which means we have to jump through some hoops. > > > > Could you do the move in cgroup_exit() in the CONFIG_PREEMPT case? > > I'm not really comfortable relying on that.. voluntary might just grow a > cond_resched() somewhere in the exit path and lead us down the same > path, also I think that !preempt smp might have the same race.
Yeah, good point.
-Mike
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