All of lore.kernel.org
 help / color / mirror / Atom feed
From: Matthew Wilcox <willy@infradead.org>
To: Bob Peterson <rpeterso@redhat.com>
Cc: Dave Chinner <david@fromorbit.com>,
	Andreas Gruenbacher <agruenba@redhat.com>,
	Christoph Hellwig <hch@infradead.org>,
	"Darrick J . Wong" <darrick.wong@oracle.com>,
	linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH] iomap: Make sure iomap_end is called after iomap_begin
Date: Tue, 16 Jun 2020 06:23:18 -0700	[thread overview]
Message-ID: <20200616132318.GZ8681@bombadil.infradead.org> (raw)
In-Reply-To: <315900873.34076732.1592309848873.JavaMail.zimbra@redhat.com>

On Tue, Jun 16, 2020 at 08:17:28AM -0400, Bob Peterson wrote:
> ----- Original Message -----
> > > I'd assume Andreas is looking at converting a filesystem to use iomap,
> > > since this problem only occurs for filesystems which have returned an
> > > invalid extent.
> > 
> > Well, I can assume it's gfs2, but you know what happens when you
> > assume something....
> 
> Yes, it's gfs2, which already has iomap. I found the bug while just browsing
> the code: gfs2 takes a lock in the begin code. If there's an error,
> however unlikely, the end code is never called, so we would never unlock.
> It doesn't matter to me whether the error is -EIO because it's very unlikely
> in the first place. I haven't looked back to see where the problem was
> introduced, but I suspect it should be ported back to stable releases.

It shouldn't just be "unlikely", it should be impossible.  This is the
iomap code checking whether you've returned an extent which doesn't cover
the range asked for.  I don't think it needs to be backported, and I'm
pretty neutral on whether it needs to be applied.

  reply	other threads:[~2020-06-16 13:23 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-06-15 16:02 [PATCH] iomap: Make sure iomap_end is called after iomap_begin Andreas Gruenbacher
2020-06-15 23:32 ` Dave Chinner
2020-06-15 23:44   ` Matthew Wilcox
2020-06-16  0:39     ` Dave Chinner
2020-06-16 12:17       ` Bob Peterson
2020-06-16 13:23         ` Matthew Wilcox [this message]
2020-06-16 13:57           ` Andreas Gruenbacher
2020-06-16 16:25             ` Darrick J. Wong
2020-06-16 16:34               ` Andreas Grünbacher
2020-06-16 16:38               ` Bob Peterson
2020-06-17 23:44                 ` Dave Chinner
2020-06-18  1:39 ` Darrick J. Wong
2020-06-18 12:21   ` Andreas Gruenbacher
2020-06-18 12:32   ` Matthew Wilcox
2020-06-18 12:37     ` Andreas Gruenbacher
2020-06-18 13:56       ` Christoph Hellwig
2020-06-18 15:15         ` Matthew Wilcox
2020-06-19 13:18           ` Christoph Hellwig

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200616132318.GZ8681@bombadil.infradead.org \
    --to=willy@infradead.org \
    --cc=agruenba@redhat.com \
    --cc=darrick.wong@oracle.com \
    --cc=david@fromorbit.com \
    --cc=hch@infradead.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-xfs@vger.kernel.org \
    --cc=rpeterso@redhat.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.