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From:   Miklos Szeredi <miklos@szeredi.hu>
Date:   Tue, 15 Jan 2019 16:37:18 +0100
Message-ID: <CAJfpegvOgA+Wd3vTRqYQP7p_SJ11YCffquP_R=WRHwqYD4b=Ng@mail.gmail.com>
Subject: Re: [PATCH 1/2] fuse: Fix race in fuse_writepage_in_flight()
To:     Kirill Tkhai <ktkhai@virtuozzo.com>
Cc:     linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
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On Thu, Jan 10, 2019 at 12:03 PM Kirill Tkhai <ktkhai@virtuozzo.com> wrote:
>
> On 10.01.2019 14:00, Miklos Szeredi wrote:
> > On Thu, Jan 10, 2019 at 11:48 AM Kirill Tkhai <ktkhai@virtuozzo.com> wrote:
> >>
> >> Hi, Miklos,
> >>
> >> any comments about this?
> >
> > Is there a reproducer?  ISTR that fsx-linux with mmaps enabled was
> > good for stressing the writeback_cache code.
>
> There is no a reproducer, since I found that by eyes during preparation of another patchset.

That's good.  It would even better to have a reproducer, but it
doesn't look easy...

Completely redid this and reordered the patchset so this change is
made before the locking changes actually introduce the bug.  See
fuse.git#for-next.

Thanks,
Miklos