On 02/07/2014 03:13 PM, Steven Rostedt wrote: > On Fri, 7 Feb 2014 09:08:34 -0500 > Steven Rostedt <[email protected]> wrote: > > >>> could you please tell me which two locks are invovled here? > > I should have also stated that it was only one lock that was involved. > But the lock owner was doing a msleep() that requires a wakeup by > ksoftirqd to continue. If ksoftirqd happens to be blocked on a lock > held by the msleep() caller, then you have your deadlock.
That makes sense. > It's best not to have any softirqs going to sleep requiring another > softirq to wake it up. Note, if we ever require a timer softirq to do a > cpu_chill() it will most definitely hit this deadlock. Yes. And that sleep in softirq is also not really nice but this isn't new. Thanks for the patch & explanation. > > -- Steve Sebastian -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
