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Date: Tue, 31 Aug 2010 08:34:28 -0500
From: Anthony Liguori <anthony@codemonkey.ws>
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Subject: Re: [Qemu-devel] Re: [PATCH 5/5] RFC: distinguish warm reset from
	cold reset.
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To: Avi Kivity <avi@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>, glommer@redhat.com, qemu-devel@nongnu.org, blauwirbel@gmail.com, Isaku Yamahata <yamahata@valinux.co.jp>, alex.williamson@redhat.com

On 08/31/2010 08:29 AM, Avi Kivity wrote:
> Note, for most devices there's no difference.  x86 has INIT and RESET, 
> with the keyboard controller RESET signal sometimes wired to INIT, and 
> RAM doesn't have RESET.  Otherwise most devices don't see a difference.

Yes, that's why I'm wondering if we can just get away with using a 
simple reset() callback and for the handful of devices that don't do a 
full reset, they can just move the state unaffected by warm reset to 
->init().

For cold reset, I'd rather approach it as a device destroy + create.  
This means that given a DeviceState, we need to collect enough 
information to recreate the device.  I'm not 100% sure we have that 
today but if we solve that problem, it means we can migrate the device 
tree during migration which is a feature I'd really like to see.

Regards,

Anthony Liguori