Messages in this thread | | | Date | Thu, 8 Sep 2005 10:09:05 +0800 | From | Coywolf Qi Hunt <> | Subject | Re: A couple of OOM killer races |
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On 9/2/05, Richard Hayden <rahaydenuk@yahoo.co.uk> wrote: > Hi all, > > It appears there is no protection in badness() (called by > out_of_memory() for each process) when it reads p->mm->total_vm. Another > processor (or a kernel preemption) could presumably run do_exit and then > exit_mm, freeing the process in question's reference to its mm just > after the (!p->mm) check but before it reads p->mm->total_vm, making the > latter reference a null pointer reference.
We have read_lock(&tasklist_lock); .
> > Also there appears to be no protection when we set p->time_slice in > __oom_kill_task(). Am I right in thinking that this field should be > protected by the appropriate runqueue lock, at least this is what > scheduler_tick() seems to use?
ditto
-- Coywolf Qi Hunt http://sosdg.org/~coywolf/ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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