From: Jack Wang <jinpu.wang@profitbricks.com>
To: Dongsu Park <dongsu.park@profitbricks.com>,
qemu-devel <qemu-devel@nongnu.org>
Cc: kwolf@redhat.com, Paolo Bonzini <pbonzini@redhat.com>,
NeilBrown <neilb@suse.de>, Stefan Hajnoczi <stefanha@redhat.com>
Subject: [Qemu-devel] [RFC] O_EXCL or not open block device
Date: Thu, 12 Sep 2013 13:27:32 +0200 [thread overview]
Message-ID: <5231A524.2080103@profitbricks.com> (raw)
Hi all,
We're using qemu export md-raid to guest OS, and we saw deadlock on
MD(which is already fixed by Neil), please see thread below:
> http://marc.info/?l=linux-raid&m=137894040228125&w=2
As Neil suggested it would be good for userspace applications to call
open() with O_EXCL flag, to avoid such MD hanging problems at the begining.
And we checked qemu, it looks it doesn't include O_EXCL flag when open
block device.
After search in the mail list we found there are a similar discussion:
https://lists.nongnu.org/archive/html/qemu-devel/2011-04/msg00722.html
> To O_EXCL or not to O_EXCL open host_cdrom
Which looks prefer enable O_EXCL, but I checked latest qemu tree, there
no such code, could anyone give comments on this?
Best regards,
Jack
next reply other threads:[~2013-09-12 11:26 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-09-12 11:27 Jack Wang [this message]
2013-09-12 13:58 ` [Qemu-devel] [RFC] O_EXCL or not open block device Stefan Hajnoczi
2013-09-12 14:27 ` Kevin Wolf
2013-09-12 15:57 ` Jack Wang
2013-09-12 22:48 ` NeilBrown
2013-09-13 7:16 ` Paolo Bonzini
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=5231A524.2080103@profitbricks.com \
--to=jinpu.wang@profitbricks.com \
--cc=dongsu.park@profitbricks.com \
--cc=kwolf@redhat.com \
--cc=neilb@suse.de \
--cc=pbonzini@redhat.com \
--cc=qemu-devel@nongnu.org \
--cc=stefanha@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 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).