On 12/16/2016 02:14 PM, Vegard Nossum wrote:
On 12/16/2016 11:11 AM, Michal Hocko wrote:
On Fri 16-12-16 10:43:52, Vegard Nossum wrote:
[...]
I don't think it's a bug in the OOM reaper itself, but either of the
following two patches will fix the problem (without my understand how or
why):
What is the atual crash?
Annoyingly it doesn't seem to reproduce with the very latest
linus/master, so maybe it's been fixed recently after all and I missed it.
I've started a bisect to see what fixed it. Just in case, I added 4
different crashes I saw with various kernels. I think there may have
been a few others too (I remember seeing one in a page fault path), but
these were the most frequent ones.
The bisect points to:
commit 6b94780e45c17b83e3e75f8aaca5a328db583c74
Author: Vincent Guittot <vincent.guittot@xxxxxxxxxx>
Date: Thu Dec 8 17:56:54 2016 +0100
sched/core: Use load_avg for selecting idlest group
as fixing the crash, which seems odd to me. The only bit that sticks out
from the changelog to me:
"""
For use case like hackbench, this enable the scheduler to select
different CPUs during the fork sequence and to spread tasks across the
system.
"""
Reverting it from linus/master doesn't reintroduce the crash, but the
commit just before (6b94780e4^) does crash, so I'm not sure what's going
on. Maybe the crash is just really sensitive to scheduling decisions or
something.
Vegard
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>