On Wed, May 21, 2014 at 09:08:26AM -0400, Sasha Levin wrote: > On 05/20/2014 09:03 AM, Sasha Levin wrote: > > On 05/20/2014 07:04 AM, Peter Zijlstra wrote: > >> > On Mon, May 19, 2014 at 10:05:31PM -0400, Sasha Levin wrote: > >>> >> ping? It seems to be easy enough to reproduce on -next, I'd be happy > >>> >> to try > >>> >> debug patches/fixes. > >> > > >> > Does this fuzzing you do also include hotplug? If so, does disabling > >> > that make this problem go away? > >> > > > There were no hotplug operations going on when this happens, so it seems > > unrelated. > > I've added a small test: > > diff --git a/kernel/sched/core.c b/kernel/sched/core.c > index 927fa33..b5e11c7 100644 > --- a/kernel/sched/core.c > +++ b/kernel/sched/core.c > @@ -1154,6 +1156,7 @@ int migrate_swap(struct task_struct *cur, struct > task_struct *p) > goto out; > > trace_sched_swap_numa(cur, arg.src_cpu, p, arg.dst_cpu); > + BUG_ON(cur == p); > ret = stop_two_cpus(arg.dst_cpu, arg.src_cpu, migrate_swap_stop, > &arg); > > out: > > > Which seems to get hit. This sounds like a race with task moving to > other cpu maybe?
Oi, good call that, lemme go stare. -- 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/
