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Date: Wed, 8 Jul 2009 16:49:22 +0300
From: Gleb Natapov <gleb@redhat.com>
Subject: Re: [Qemu-devel] [PATCH][RESEND] Add monitor command for system_reboot
Message-ID: <20090708134922.GQ28046@redhat.com>
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To: Anthony Liguori <aliguori@us.ibm.com>
Cc: Ryan Harper <ryanh@us.ibm.com>, qemu-devel@nongnu.org

On Wed, Jul 08, 2009 at 08:05:20AM -0500, Anthony Liguori wrote:
> Gleb Natapov wrote:
>> On Tue, Jul 07, 2009 at 02:26:31PM -0500, Ryan Harper wrote:
>>   
>>> Add a new monitor command (system_reboot) for a soft reboot which uses
>>> system_powerdown to trigger ACPI shutdown in the guest and once shutdown
>>> is complete, trigger a reset instead of exiting qemu.
>>>
>>> Depends on commit a6d6552426dcbf726e5549f08b70c9318d6be14b which enabled
>>> ACPI power button support.
>>>
>>> V2:
>>>     -added reset handler to lower the reboot flag on reset.
>>>     
>> OS is free to ignore ACPI shutdown request and in this case
>> reboot_requested will not be reset. On the next user initiated
>> guest power down qemu will reboot instead of exit.
>>   
>
> Indeed.  This is what has kept me from applying this but I just can't  
> think of any better solution.
>
> Any ideas?
>
> The drive behind implementing this feature is so that we can implement a  
> proper virDomainReboot in libvirt.
>
I don't know what is the definition of virDomainReboot is, but what this
patch is trying to do is to change a guest OS behaviour from the host.
Guest OSes can control their behaviour on ACPI shutdown event by
themselves (on Windows you can configure what power button action should
be, on Linux I don't know I never power it down), so why would we want
to override this? 

--
			Gleb.