Comment 8 for bug 1497428

Dan,

  Just checking in with a status update. Our main system experiencing the issue is a production system, so loading the custom kernel wasn’t an option at the time. I have since created a clone of our production server and am trying to reproduce the issue now.

  I will let you know once the issue reoccurs on our cloned environment.

Dave Muysson | Cloud Architect
dave.muysson@360pi.com <mailto:dave.muysson@360pi.com> |​ (613) 562-2525 x 510 <tel:6135622525,510> |​ 360pi.com <http://360pi.com/>

> On Oct 13, 2015, at 9:37 AM, Dave Muysson <dave.muysson@360pi.com> wrote:
>
> Dan,
>
> I haven’t tried to directly reproduce the bug, but I have a few ideas. If I can free up some time I’ll see if I can reproduce it.
>
>
> Dave Muysson | Cloud Architect
> dave.muysson@360pi.com <mailto:dave.muysson@360pi.com> |​ (613) 562-2525 x 510 <tel:6135622525,510> |​ 360pi.com <http://360pi.com/>
>
>
>
>> On Oct 13, 2015, at 9:20 AM, Dan Streetman <<email address hidden> <mailto:<email address hidden>>> wrote:
>>
>> Hi Dave,
>>
>> are you able to reproduce the bug? The trace by itself isn't terribly helpful, all it really says is the pageblock spans zones, which means move_freepages_block() logic for detecting that failed for some reason. I have a debug kernel ppa here:
>> pad.lv/ppa/ddstreet/lp1497428
>>
>> that includes additional debug if the problem happens (it also should
>> prevent the BUG()). If you can use that kernel to trigger this and send
>> the resulting debug output it would help very much :-)
>>
>> when the problem reproduces, in the system log you should see:
>> page_zone(start_page) !=page_zone(end_page)
>>
>> and more debug following that. It should not trigger BUG() though, so
>> you may need to check the logs periodically.
>>
>> Thanks!
>>
>> --
>> You received this bug notification because you are subscribed to the bug
>> report.
>> https://bugs.launchpad.net/bugs/1497428 <https://bugs.launchpad.net/bugs/1497428>
>>
>> Title:
>> kernel BUG at /build/buildd/linux-3.13.0/mm/page_alloc.c:968
>>
>> Status in linux package in Ubuntu:
>> In Progress
>> Status in linux source package in Trusty:
>> In Progress
>>
>> Bug description:
>> The kernel triggers a BUG when it finds it is in move_freepages() but
>> the start and end pfns for the move are in different zones.
>>
>> To manage notifications about this bug go to:
>> https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1497428/+subscriptions
>