As the result of bisection, it turned out that commit
f4bdb2697ccc9cecf1a9de86905c309ad901da4c on 5.3.y
("mm/filemap.c: don't initiate writeback if mapping has no dirty pages")
triggers the crash.
This patch was back ported from upstream kernel 5.4-rc1, and
applied to 4.19.84 as well.
Will look into the change further and why it doesn't hit latest
kernels (5.4-rc8, etc).
Regards,
Ryusuke Konishi
On Wed, Nov 20, 2019 at 12:46 AM Ryusuke Konishi
<konishi.ryusuke@xxxxxxxxx> wrote:
>
> Yeah, this looks a regression of the 5.3.11 stable kernel.
>
> I could reproduce the crash with 5.3.11.
>
> 5.3, 5.3.10 and 5.4-rc8 all worked fine.
>
> The regression would be identified by bisecting commits
> between kernel 5.3.10 and 5.3.11.
>
> Thanks,
> Ryusuke Konishi
>
> 2019年11月19日(火) 23:40 <linux-nilfs-ml.via.forwarder@xxxxxxxxxxxx>:
> >
> > I believe I have the same issue as Walton Hoops.
> >
> > I do not have a serial console, and all my filesystems are NILFS2,
> >
> > so I do not currently have an easy means to capture the crash.
> >
> > However, I experienced the same Kernel BUG on upgrading to kernel 5.11
> >
> > from 5.10. Reverting back to 5.10 results in a clean boot.
> >
> > The actual kernels I use are the Ubuntu 'mainline kernels'
> >
> > 5.3.10-050310-generic works
> >
> > 5.3.11-050311-generic crashes with Kernel BUG.
> >
> > So I suspect a change between those two versions has triggered the problem.
> >
> >
