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Date: Tue, 13 Dec 2011 11:06:50 +0100
From: Gerd Hoffmann <kraxel@redhat.com>
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Subject: Re: [Qemu-devel] Dropping the MONITOR_CMD_ASYNC
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To: Anthony Liguori <anthony@codemonkey.ws>
Cc: Stefan Hajnoczi <stefanha@gmail.com>, Luiz Capitulino <lcapitulino@redhat.com>, Yonit Halperin <yhalperi@redhat.com>, qemu-devel <qemu-devel@nongnu.org>, stefanha@linux.vnet.ibm.com

  Hi,

> We aren't breaking an ABI here.  libvirt can detect that this command is
> gone and probe for the new command.

Please stop this.  There are libvirt versions in the wild which can't
deal with this and thus will break, no matter how hard you try to wave
it away.  The question is not whenever something breaks or not, the
question is how to deal with the breakage best.

Zapping async monitor commands *now* (i.e. early in the 1.1 release
cycle) is probably the best way to handle it.  It gives the libvirt
folks time to get a new release out of the door before 1.1-final is
released, which in turn allows distros to minimize the user-visible fallout.

Technically the switch is easy: migrate_connect_complete_cb() is called
from spice-server on completion, we just have to emit a qmp event there
instead of calling the monitor completion callback.

cheers,
  Gerd