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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Tue, 6 Jun 2023 05:55:19 -0700
Message-ID: <CAHk-=wi_P4tOWCbZYo11u5vbB+tTxCSGwKC9m71y-QdbZP8zKA@mail.gmail.com>
Subject: Re: [GIT PULL] gfs2 fix
To:     Andreas Gruenbacher <agruenba@redhat.com>
Cc:     cluster-devel@redhat.com, linux-kernel@vger.kernel.org
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On Tue, Jun 6, 2023 at 5:48=E2=80=AFAM Andreas Gruenbacher <agruenba@redhat=
.com> wrote:
>
> - Don't get stuck writing page onto itself under direct I/O.

Btw, is there a test for this DIO case?

We've had the deadlock issue on t page lock (or for inode locks or
whatever) for normal IO when faulting in the same page that is written
to, and we have as pattern for solving that and I think there are
filesystem tests that trigger this.

But the DIO pattern is a bit different, with the whole "invalidate
page cache: issue, and the fact that you send this patch now (rather
than years ago) makes me wonder about test coverage for this all?

                Linus