qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: Fam Zheng <famz@redhat.com>
To: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>,
	Kevin Wolf <kwolf@redhat.com>
Cc: qemu-block@nongnu.org, qemu-devel@nongnu.org, mreitz@redhat.com,
	stefanha@redhat.com, den@openvz.org, pbonzini@redhat.com,
	jsnow@redhat.com
Subject: Re: [Qemu-devel] [PATCH] blk: fix aio context loss on media change
Date: Wed, 15 Mar 2017 21:13:43 +0800	[thread overview]
Message-ID: <20170315131343.GF3088@lemon.lan> (raw)
In-Reply-To: <20170315120656.GI4030@noname.str.redhat.com>

On Wed, 03/15 13:06, Kevin Wolf wrote:
> > > 
> > > Stefan, Paolo, do you remember the details why we didn't even do a
> > > simple fix like the one below? I think there were some patches on the
> > > list, no?
> > 
> > ISTM the concern was mostly "what about other BB in the graph?"
> > 
> > Should the new op blocker API be used in this one (a new type of perm)?
> 
> If we know what operation to block, that's an option. Would "change the
> node's AioContext" work for it?
> 
> I think it would effectively mean that you need to attach the device
> first and then jobs etc. respect the AioContext, whereas the opposite
> order breaks because they don't have callbacks to adjust the AioContext
> after the fact.
> 
> This seems to match what's actually safe, so it might really be as easy
> as this.

Yes, this sounds good to me.

Vladimir, would you like to implement this? It would be good to have this fixed
in 2.9.

Fam

  reply	other threads:[~2017-03-15 13:13 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-03-14 17:11 [Qemu-devel] [PATCH] blk: fix aio context loss on media change Vladimir Sementsov-Ogievskiy
2017-03-15 11:03 ` Kevin Wolf
2017-03-15 11:14   ` Fam Zheng
2017-03-15 12:06     ` Kevin Wolf
2017-03-15 13:13       ` Fam Zheng [this message]
2017-03-15 14:04         ` Vladimir Sementsov-Ogievskiy
2017-03-15 14:42           ` Fam Zheng
2017-03-15 13:39   ` Paolo Bonzini
2017-03-15 14:30     ` Kevin Wolf
2017-03-15 14:43       ` Paolo Bonzini
2017-03-15 15:02         ` Kevin Wolf
2017-03-15 15:09           ` Paolo Bonzini
2017-03-15 15:30             ` Kevin Wolf

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=20170315131343.GF3088@lemon.lan \
    --to=famz@redhat.com \
    --cc=den@openvz.org \
    --cc=jsnow@redhat.com \
    --cc=kwolf@redhat.com \
    --cc=mreitz@redhat.com \
    --cc=pbonzini@redhat.com \
    --cc=qemu-block@nongnu.org \
    --cc=qemu-devel@nongnu.org \
    --cc=stefanha@redhat.com \
    --cc=vsementsov@virtuozzo.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).