Re: [Bug 199931] New: systemd/rtorrent file data corruption when using echo 3 >/proc/sys/vm/drop_caches

Andrew Morton
2018-06-05T21:38:47Z

On Wed, 6 Jun 2018 06:22:25 +0900 Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> wrote:

> On 2018/06/06 5:03, Andrew Morton wrote:
> >
> > (switched to email. Please respond via emailed reply-to-all, not via the
> > bugzilla web interface).
> >
> > On Tue, 05 Jun 2018 18:01:36 +0000 bugzilla-daemon@bugzilla.kernel.org wrote:
> >
> >> https://bugzilla.kernel.org/show_bug.cgi?id=199931
> >>
> >> Bug ID: 199931
> >> Summary: systemd/rtorrent file data corruption when using echo
> >> 3 >/proc/sys/vm/drop_caches
> >
> > A long tale of woe here. Chris, do you think the pagecache corruption
> > is a general thing, or is it possible that btrfs is contributing?
>
> According to timestamp of my testcases, I was observing corrupted-bytes issue upon OOM-kill
> (without using btrfs) as of 2017 Aug 11. Thus, I don't think that this is specific to btrfs.
> But I can't find which patch fixed this issue.

That sounds different. Here, the corruption is caused by performing
drop_caches, not by an oom-killing.