Re: mm, vmstat: kernel BUG at mm/vmstat.c:1408!

From: Sasha Levin
Date: Wed Jan 20 2016 - 10:50:06 EST


On 01/20/2016 10:20 AM, Christoph Lameter wrote:
> On Wed, 20 Jan 2016, Michal Hocko wrote:
>
>> > On Wed 20-01-16 09:56:26, Sasha Levin wrote:
>>> > > On 01/20/2016 09:37 AM, Michal Hocko wrote:
>>>> > > > I am just reading through this old discussion again because "vmstat:
>>>> > > > make vmstat_updater deferrable again and shut down on idle" which seems
>>>> > > > to be the culprit AFAIU has been merged as 0eb77e988032 and I do not see
>>>> > > > any follow up fix merged to linus tree
>>> > >
>>> > > So this isn't an "old" discussion - the bug is very much there and I can
>>> > > hit it easily. As a workaround I've "disabled" vmstat.
>> >
>> > Well the report is since 18th Dec which is over month old. Should we
>> > revert 0eb77e988032 as a pre caution and make sure this is done properly
>> > in -mm tree. AFAIR none of the proposed fix worked without other
>> > fallouts?
> Seems that we are unable to get enough information to reproduce the issue?

As I've mentioned - this reproduces frequently. I'd be happy to add in debug
information into the kernel that might help you reproduce it, but as it seems
like a timing issue, I can't provide a simple reproducer.


Thanks,
Sasha