From: Anthony Liguori <anthony@codemonkey.ws>
To: Gerd Hoffmann <kraxel@redhat.com>
Cc: jes sorensen <jes.sorensen@redhat.com>,
Juan Quintela <quintela@redhat.com>,
"qemu-devel@nongnu.org" <qemu-devel@nongnu.org>,
Markus Armbruster <armbru@redhat.com>
Subject: Re: [Qemu-devel] migration: new sections and backward compatibility.
Date: Wed, 06 Jul 2011 12:13:42 -0500 [thread overview]
Message-ID: <4E1497C6.4060505@codemonkey.ws> (raw)
In-Reply-To: <4E148776.4000805@redhat.com>
On 07/06/2011 11:04 AM, Gerd Hoffmann wrote:
> Hi folks,
>
> We'll need to figure a sane way to handle migration to older versions
> with new sections, i.e. devices which used to not save state before do now.
>
> We already have one case in tree: usb. qemu 0.14 saves state for usb-hid
> devices and the usb-hub, whereas qemu 0.13 and older don't. You can't
> migrate a vm with a usb-tablet from 0.14 to 0.13 because of that even if
> you use -M pc-0.13.
Because if you did migrate, you would actively break the guest during
migration. So why is this a problem?
This comes up a lot. We shouldn't enable migration if we know the guest
is going to break during migration. That's a feature, not a bug.
Regards,
Anthony Liguori
next prev parent reply other threads:[~2011-07-06 17:13 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-07-06 16:04 [Qemu-devel] migration: new sections and backward compatibility Gerd Hoffmann
2011-07-06 17:13 ` Anthony Liguori [this message]
2011-07-07 7:19 ` Gerd Hoffmann
2011-07-07 15:36 ` Anthony Liguori
2011-07-12 14:50 ` Gerd Hoffmann
2011-07-07 9:23 ` Markus Armbruster
2011-07-07 11:02 ` Alexander Graf
2011-07-07 15:23 ` Paolo Bonzini
2011-07-11 15:32 ` Kevin Wolf
2011-07-11 15:31 ` Paolo Bonzini
2011-07-07 14:40 ` Gerd Hoffmann
2011-07-07 15:37 ` Anthony Liguori
2011-07-07 16:44 ` Markus Armbruster
2011-07-06 17:28 ` Avi Kivity
2011-07-06 20:01 ` Anthony Liguori
2011-07-06 23:32 ` Alexander Graf
2011-07-07 7:14 ` Gerd Hoffmann
2011-07-07 7:30 ` Avi Kivity
2011-07-08 13:02 ` Jes Sorensen
2011-07-08 14:43 ` Peter Maydell
2011-07-08 15:12 ` Gerd Hoffmann
2011-07-07 15:33 ` Anthony Liguori
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