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From:   David Howells <dhowells@redhat.com>
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To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     dhowells@redhat.com, David Sterba <dsterba@suse.cz>,
        Eric Biggers <ebiggers@kernel.org>,
        Al Viro <viro@zeniv.linux.org.uk>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 0/2] pipe: Fixes [ver #2]
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Date:   Fri, 06 Dec 2019 21:26:12 +0000
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Linus Torvalds <torvalds@linux-foundation.org> wrote:

> I think I found it.
>=20
> TOTALLY UNTESTED patch appended. It's whitespace-damaged and may be
> completely wrong. And might not fix it.
>=20
> The first hunk is purely syntactic sugar - use the normal head/tail
> order. The second/third hunk is what I think fixes the problem:
> iter_file_splice_write() had the same buggy "let's cache
> head/tail/mask" pattern as pipe_write() had.
>=20
> You can't cache them over  a 'pipe_wait()' that drops the pipe lock,
> and there's one in splice_from_pipe_next().

That seems to fix it.

Tested-by: David Howells <dhowells@redhat.com>