Re: PANIC: mm: memcg/slab: percpu_ref_put_many - Unable to handle kernel paging request at virtual address ffff80096d78f000

From: Naresh Kamboju
Date: Thu Jul 02 2020 - 11:58:20 EST


On Wed, 1 Jul 2020 at 13:49, Michal Hocko <mhocko@xxxxxxxxxx> wrote:
>
> On Wed 01-07-20 13:24:54, Naresh Kamboju wrote:
> > While running LTP mm test suite on arm64 Juno device the kernel panic
> > noticed on linux-next 20200630 tag.
>
> Can you try to bisect? The new memcg slab allocator series sounds like a
> potential candidate. One of the patches has changed the memcg reference
> counting which is showing up on the stack. This might be a side effect
> of something else of course but bisection would tell us more.

The reported problem is fixed by a patch proposed in this email thread.
https://lore.kernel.org/linux-mm/20200701184552.GA61684@xxxxxxxxxxxxxxxxxxxxxxxxxxx/

- Naresh

>
> Thanks
>
> --
> Michal Hocko
> SUSE Labs