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From:   Miklos Szeredi <mszeredi@redhat.com>
Date:   Wed, 24 Nov 2021 10:23:06 +0100
Message-ID: <CAOssrKez1mnF4rWRvWgk4LJ2iDfX8xkpMKvgprFt+-ARs83=nA@mail.gmail.com>
Subject: Re: [PATCH 5.15 056/917] fuse: fix page stealing
To:     Justin Forbes <jmforbes@linuxtx.org>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Stable <stable@vger.kernel.org>,
        Frank Dinoff <fdinoff@google.com>
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On Wed, Nov 24, 2021 at 1:40 AM Justin Forbes <jmforbes@linuxtx.org> wrote:
> Thanks, did a scratch build for that and dropped it in the bug. Only
> one user has reported back, but the report was that it did not fix the
> issue.  I have also gotten confirmation now that the issue is occuring
> with 5.16-rc2.

Okay.

Morning light brings clarity to the mind.  Here's a patch that should
definitely fix this bug, as well as the very unlikely race of the page
being truncated from the page cache before pipe_buf_release() is
called.

Please test.

Thanks,
Miklos

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