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Reply-To: fdmanana@gmail.com
From:   Filipe Manana <fdmanana@gmail.com>
Date:   Fri, 2 Nov 2018 12:04:39 +0000
Message-ID: <CAL3q7H5ofBmjh0DmbPH6Rmm523JV9byuBiYj=Jxpc44Kbh+Haw@mail.gmail.com>
Subject: Re: [PATCH 05/25] vfs: avoid problematic remapping requests into
 partial EOF block
To:     Dave Chinner <david@fromorbit.com>
Cc:     "Darrick J. Wong" <darrick.wong@oracle.com>,
        Eric Sandeen <sandeen@redhat.com>, linux-nfs@vger.kernel.org,
        linux-cifs@vger.kernel.org, linux-unionfs@vger.kernel.org,
        linux-xfs@vger.kernel.org, linux-mm@kvack.org,
        linux-btrfs <linux-btrfs@vger.kernel.org>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        ocfs2-devel@oss.oracle.com
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On Mon, Oct 15, 2018 at 1:31 AM Dave Chinner <david@fromorbit.com> wrote:
>
> On Fri, Oct 12, 2018 at 09:22:18PM +0100, Filipe Manana wrote:
> > On Thu, Oct 11, 2018 at 5:13 AM Darrick J. Wong <darrick.wong@oracle.co=
m> wrote:
> > >
> > > From: Darrick J. Wong <darrick.wong@oracle.com>
> > >
> > > A deduplication data corruption is exposed by fstests generic/505 on
> > > XFS.
> >
> > (and btrfs)
> >
> > Btw, the generic test I wrote was indeed numbered 505, however it was
> > never committed and there's now a generic/505 which has nothing to do
> > with deduplication.
> > So you should update the changelog to avoid confusion.
>
> What test is it now? And if it hasn't been committed, are you going
> to update it and repost as it clearly had value....

Sorry, I lost track of this.

So what was the conclusion of the thread where discussion about this
problem started?
It wasn't clear to me if a consensus was reached and got lost on that
long user space dedupe tools discussion between you and Zygo.

The test assumed a fix of rounding down the range and deduping less
bytes then requested (which ended up included in 4.19 for btrfs).

From this vfs patch it seems it was decided to return errno -EDADE instead.
Is this the final decision?

>
> Cheers,
>
> Dave.
> --
> Dave Chinner
> david@fromorbit.com


--=20
Filipe David Manana,

=E2=80=9CWhether you think you can, or you think you can't =E2=80=94 you're=
 right.=E2=80=9D