Re: ext4 corruption on alpha with 4.20.0-09062-gd8372ba8ce28

From: Jan Kara
Date: Tue Feb 19 2019 - 08:20:30 EST


On Tue 19-02-19 14:17:09, Meelis Roos wrote:
> > > > > The result of the bisection is
> > > > > [88dbcbb3a4847f5e6dfeae952d3105497700c128] blkdev: avoid migration stalls for blkdev pages
> > > > >
> > > > > Is that result relevant for the problem or should I continue bisecting between 4.20.0 and the so far first bad commit?
> > > >
> > > > Can you try reverting the commit and see if it makes the problem go away?
> > >
> > > Tried reverting it on top of 5.0.0-rc6-00153-g5ded5871030e and it seems
> > > to make the kernel work - emerge --sync succeeded.
> There is more to it.
>
> After running 5.0.0-rc6-00153-g5ded5871030e-dirty (with the revert of
> that patch) successfully for Gentoo update, I upgraded the kernel to
> 5.0.0-rc7-00011-gb5372fe5dc84-dirty (todays git + revert of this patch)
> and it broke on rsync again:
>
> RepoStorageException: command exited with status -6: rsync -a --link-dest /usr/portage --exclude=/distfiles --exclude=/local --exclude=/lost+found --exclude=/packages --exclude /.tmp-unverified-download-quarantine /usr/portage/ /usr/portage/.tmp-unverified-download-quarantine/
>
> Nothing in dmesg.
>
> This means the real root reason is somewhere deeper and reverting this
> commit just made it less likely to happen.

Thanks for information. Yeah, that makes somewhat more sense. Can you ever
see the failure if you disable CONFIG_TRANSPARENT_HUGEPAGE? Because your
findings still seem to indicate that there' some problem with page
migration and Alpha (added MM list to CC).

Honza
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR