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Date: Thu, 23 Aug 2012 14:42:00 +0100
From: "Daniel P. Berrange" <berrange@redhat.com>
Message-ID: <20120823134200.GH10833@redhat.com>
References: <1345728155-11667-1-git-send-email-aliguori@us.ibm.com>
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Subject: Re: [Qemu-devel] [PATCH] monitor: move json init from OPEN event to
	init
Reply-To: "Daniel P. Berrange" <berrange@redhat.com>
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To: Anthony Liguori <aliguori@us.ibm.com>
Cc: qemu-devel@nongnu.org

On Thu, Aug 23, 2012 at 08:22:35AM -0500, Anthony Liguori wrote:
> At some point in the past, the OPEN event was changed to be issued from a
> bottom half.  This creates a small window whereas a data callback registered in
> init may be invoked before the OPEN event has been issued.
> 
> This is reproducible with:
> 
>  echo "{'execute': 'qmp_capabilities'}" | qemu-system-x86_64 -M none -qmp stdio
> 
> We can fix this for the monitor by moving the parser initialization to init.
> 
> The remaining state that is set in OPEN appears harmless.
> 
> Reported-by: Daniel Berrange <berrange@redhat.com>
> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>

Works in my testing. I have also fixed libvirt so that it does not try
to send commands to QMP, until QMP has sent out its initial greeting,
thus avoiding the flaw too.

Daniel
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