mbox series

[GIT,PULL] gfs2 fix

Message ID 20230606124800.1151665-1-agruenba@redhat.com
State New
Headers
Series [GIT,PULL] gfs2 fix |

Pull-request

git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2.git tags/gfs2-v6.4-rc4-fix

Message

Andreas Gruenbacher June 6, 2023, 12:48 p.m. UTC 
  Hi Linus,

please consider pulling the following fix.

Thanks,
Andreas

The following changes since commit 48b1320a674e1ff5de2fad8606bee38f724594dc:

  Merge tag 'for-6.4-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux (2023-05-30 17:23:50 -0400)

are available in the Git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2.git tags/gfs2-v6.4-rc4-fix

for you to fetch changes up to fa58cc888d67e640e354d8b3ceef877ea167b0cf:

  gfs2: Don't get stuck writing page onto itself under direct I/O (2023-06-01 14:55:43 +0200)

----------------------------------------------------------------
gfs2 fix

- Don't get stuck writing page onto itself under direct I/O.

----------------------------------------------------------------
Andreas Gruenbacher (1):
      gfs2: Don't get stuck writing page onto itself under direct I/O

 fs/gfs2/file.c | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

Comments

Linus Torvalds June 6, 2023, 12:55 p.m. UTC | #1 
On Tue, Jun 6, 2023 at 5:48 AM 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
pr-tracker-bot@kernel.org June 6, 2023, 1:22 p.m. UTC | #2 
The pull request you sent on Tue,  6 Jun 2023 14:48:00 +0200:

> git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2.git tags/gfs2-v6.4-rc4-fix

has been merged into torvalds/linux.git:
https://git.kernel.org/torvalds/c/0bdd0f0bf17c5aac16f348ee4b1ebf23d1ec1649

Thank you!
Andreas Gruenbacher June 6, 2023, 1:32 p.m. UTC | #3 
On Tue, Jun 6, 2023 at 2:55 PM Linus Torvalds
<torvalds@linux-foundation.org> wrote:
> On Tue, Jun 6, 2023 at 5:48 AM 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?

The previous test case I wrote for these kinds of page faults is:

  "generic: Test page faults during read and write"
  https://git.kernel.org/pub/scm/fs/xfs/xfstests-dev.git/commit/?id=d3cbdabff

I've added a check for this specific case, but this change hasn't been
posted/merged yet:

  "generic/728: Add mmap + DIO write test"
  https://gitlab.com/agruenba/xfstests/-/commit/8c37de03

> 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?

Yes, this case wasn't covered so far. The other page fault issues are
covered since 2021, and were fixed in gfs2 back then.

Thanks,
Andreas