linux-fsdevel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
To: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>,
	Alexander Viro <viro@zeniv.linux.org.uk>,
	syzbot <syzbot+10007d66ca02b08f0e60@syzkaller.appspotmail.com>,
	dvyukov@google.com, linux-fsdevel@vger.kernel.org,
	linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com,
	linux-block@vger.kernel.org
Subject: Re: INFO: task hung in __get_super
Date: Thu, 16 May 2019 21:50:51 +0900	[thread overview]
Message-ID: <e9ffd00a-809c-9eca-45b4-31449a64032e@i-love.sakura.ne.jp> (raw)
In-Reply-To: <20190516123201.GG13274@quack2.suse.cz>

On 2019/05/16 21:32, Jan Kara wrote:
> On Thu 16-05-19 21:17:14, Tetsuo Handa wrote:
>> On 2019/05/16 20:48, Jan Kara wrote:
>>> OK, so non-racy fix was a bit more involved and I've ended up just
>>> upgrading the file reference to an exclusive one in loop_set_fd() instead
>>> of trying to hand-craft some locking solution. The result is attached and
>>> it passes blktests.
>>
>> blkdev_get() has corresponding blkdev_put().
>> bdgrab() does not have corresponding bdput() ?
> 
> Yes, and that's hidden inside blkdev_put() (or failing blkdev_get()). Don't
> get me started on calling conventions of these functions... I've wasted half
> an hour trying to figure out where I'm leaking inode references in my patch
> ;).

Ah, found tricky comment. Please apply the patch. Thank you.

/**
 * blkdev_get - open a block device
 * @bdev: block_device to open
 * @mode: FMODE_* mask
 * @holder: exclusive holder identifier
 *
 * Open @bdev with @mode.  If @mode includes %FMODE_EXCL, @bdev is
 * open with exclusive access.  Specifying %FMODE_EXCL with %NULL
 * @holder is invalid.  Exclusive opens may nest for the same @holder.
 *
 * On success, the reference count of @bdev is unchanged.  On failure,
 * @bdev is put.
 *
 * CONTEXT:
 * Might sleep.
 *
 * RETURNS:
 * 0 on success, -errno on failure.
 */

  reply	other threads:[~2019-05-16 12:51 UTC|newest]

Thread overview: 28+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-04-01 17:08 INFO: task hung in __get_super syzbot
2018-06-19 11:44 ` Tetsuo Handa
2018-06-19 11:53   ` Dmitry Vyukov
2018-06-19 14:10     ` Tetsuo Handa
2018-06-19 14:15       ` Dmitry Vyukov
2018-06-20  1:15         ` Tetsuo Handa
2019-04-28 18:14 ` syzbot
2019-04-28 18:51   ` Al Viro
2019-04-29  1:38     ` Tetsuo Handa
2019-04-29  5:30     ` Dmitry Vyukov
2019-04-30  2:55     ` Jan Kara
2019-04-30  3:11       ` Al Viro
2019-04-30 13:07         ` Jan Kara
2019-04-30 13:18           ` Al Viro
2019-04-30 15:07             ` Jan Kara
2019-04-30 15:34               ` Tetsuo Handa
2019-05-03 10:29                 ` Tetsuo Handa
2019-05-14  5:15   ` Tetsuo Handa
2019-05-15  1:02   ` Tetsuo Handa
2019-05-15 10:21     ` Jan Kara
2019-05-15 11:32       ` Tetsuo Handa
2019-05-15 13:07         ` Jan Kara
2019-05-16 11:48           ` Jan Kara
2019-05-16 12:17             ` Tetsuo Handa
2019-05-16 12:32               ` Jan Kara
2019-05-16 12:50                 ` Tetsuo Handa [this message]
2019-05-16 12:33             ` syzbot
2019-05-15 11:59       ` syzbot

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=e9ffd00a-809c-9eca-45b4-31449a64032e@i-love.sakura.ne.jp \
    --to=penguin-kernel@i-love.sakura.ne.jp \
    --cc=axboe@kernel.dk \
    --cc=dvyukov@google.com \
    --cc=jack@suse.cz \
    --cc=linux-block@vger.kernel.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=syzbot+10007d66ca02b08f0e60@syzkaller.appspotmail.com \
    --cc=syzkaller-bugs@googlegroups.com \
    --cc=viro@zeniv.linux.org.uk \
    /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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).