From: Christoph Hellwig <hch@lst.de>
To: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Christoph Hellwig <hch@lst.de>,
linux-xfs@vger.kernel.org, Dave Chinner <david@fromorbit.com>,
linux-fsdevel <linux-fsdevel@vger.kernel.org>,
linux-kernel <linux-kernel@vger.kernel.org>,
Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: xfs: commit 6552321831dc "xfs: remove i_iolock and use i_rwsem in the VFS inode instead" change causes hang
Date: Sun, 8 Jan 2017 16:14:30 +0100 [thread overview]
Message-ID: <20170108151430.GA29847@lst.de> (raw)
In-Reply-To: <1483887789.8189.90.camel@linux.vnet.ibm.com>
On Sun, Jan 08, 2017 at 10:03:09AM -0500, Mimi Zohar wrote:
> But not normally for a normal file read.
Depends on the file system. In addition to XFS at least the NFS
also uses i_rwsem by default. Also all file systems supporting
a DAX I/O path.
> Unless something has changed recently, to synchronize reading files to
> calculate the file hash and writing xattrs it has to take the i_rwsem
> prior to reading the file.
No, you must simply not do this at all. If you take a lock that
belongs to the fs and is not your own over ->read_iter you're toast
as you've seen.
next prev parent reply other threads:[~2017-01-08 15:14 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-01-08 14:48 xfs: commit 6552321831dc "xfs: remove i_iolock and use i_rwsem in the VFS inode instead" change causes hang Mimi Zohar
2017-01-08 14:52 ` Christoph Hellwig
2017-01-08 15:03 ` Mimi Zohar
2017-01-08 15:14 ` Christoph Hellwig [this message]
2017-01-08 15:31 ` Mimi Zohar
2017-01-08 15:37 ` Christoph Hellwig
2017-01-08 16:38 ` Mimi Zohar
2017-01-08 16:43 ` Christoph Hellwig
2017-01-08 17:59 ` James Bottomley
2017-01-08 18:18 ` Christoph Hellwig
2017-01-08 18:57 ` James Bottomley
2017-01-08 19:09 ` Christoph Hellwig
2017-01-08 19:26 ` Al Viro
2017-01-08 20:10 ` Mimi Zohar
2017-01-08 19:39 ` Mimi Zohar
2017-01-09 19:44 ` Jeff Layton
2017-01-10 2:54 ` Mimi Zohar
2017-01-10 16:22 ` Jeff Layton
2017-01-08 19:16 ` Mimi Zohar
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=20170108151430.GA29847@lst.de \
--to=hch@lst.de \
--cc=david@fromorbit.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-xfs@vger.kernel.org \
--cc=viro@ZenIV.linux.org.uk \
--cc=zohar@linux.vnet.ibm.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 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).