On Thu, Jan 23, 2014 at 10:38:33AM -0800, Frank Mayhar wrote: > On Wed, 2014-01-22 at 07:46 -0800, Frank Mayhar wrote: > > On Tue, 2014-01-21 at 07:58 -0800, Frank Mayhar wrote: > > > Replacing? Or adding to? Is BYPASS always set when DYING is set? (My > > > guess is not but I haven't done an exhaustive analysis.) So the > > > relevant code snippet in __elv_next_request() would be: > > > if (unlikely(blk_queue_dying(q)) || > > > unlikely(blk_queue_bypass(q)) || > > > !q->elevator->type->ops.elevator_dispatch_fn(q, 0)) > > > return NULL; > > > > FYI, I've made this change and tested it. I can't say for certain that > > it fixes the crash (since it's one of those races that's difficult to > > reproduce), but it does seem to pass all the tests I've thrown at it so > > far. > > Um, does anyone care about this? Tejun? Jens? Anyone? > > This is a real crash; it would be nice if someone would weigh in.
Yeah, we're gonna fix this and I *think* replacing dying with bypass is the right thing to do as a queue is always bypassing when killed. It's probably just that we're in the earlier part of the merge window and I have some other things on my plate. Will post a patch in a couple days. Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
