linux-fsdevel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Jan Kara <jack@suse.cz>
To: Matthew Wilcox <willy@infradead.org>
Cc: Jan Kara <jack@suse.cz>, Dan Williams <dan.j.williams@intel.com>,
	linux-fsdevel@vger.kernel.org, linux-nvdimm@lists.01.org,
	Barret Rhoden <brho@google.com>
Subject: Re: [PATCH] dax: Fix deadlock in dax_lock_mapping_entry()
Date: Thu, 27 Sep 2018 15:41:29 +0200	[thread overview]
Message-ID: <20180927134129.GB8800@quack2.suse.cz> (raw)
In-Reply-To: <20180927132843.GA19006@bombadil.infradead.org>

On Thu 27-09-18 06:28:43, Matthew Wilcox wrote:
> On Thu, Sep 27, 2018 at 01:23:32PM +0200, Jan Kara wrote:
> > When dax_lock_mapping_entry() has to sleep to obtain entry lock, it will
> > fail to unlock mapping->i_pages spinlock and thus immediately deadlock
> > against itself when retrying to grab the entry lock again. Fix the
> > problem by unlocking mapping->i_pages before retrying.
> 
> It seems weird that xfstests doesn't provoke this ...

The function currently gets called only from mm/memory-failure.c. And yes,
we are lacking DAX hwpoison error tests in fstests...

								Honza
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR

  reply	other threads:[~2018-09-27 19:59 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-09-27 11:23 [PATCH] dax: Fix deadlock in dax_lock_mapping_entry() Jan Kara
2018-09-27 13:28 ` Matthew Wilcox
2018-09-27 13:41   ` Jan Kara [this message]
2018-09-27 18:22     ` Dan Williams
2018-10-04 16:27       ` Jan Kara
2018-10-05  1:57         ` Dan Williams
2018-10-05  2:52           ` Matthew Wilcox
2018-10-05  4:01             ` Dan Williams
2018-10-05  4:28               ` Dan Williams
2018-10-05  9:54                 ` Jan Kara
2018-10-06 18:04                   ` Dan Williams

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=20180927134129.GB8800@quack2.suse.cz \
    --to=jack@suse.cz \
    --cc=brho@google.com \
    --cc=dan.j.williams@intel.com \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-nvdimm@lists.01.org \
    --cc=willy@infradead.org \
    /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).