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Date: Tue, 09 Sep 2014 23:16:45 +0200
From: Alexander Graf <agraf@suse.de>
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Subject: Re: [Qemu-devel] [patch 1/3] kvmclock: Ensure time in migration
	never goes backward
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To: Marcelo Tosatti <mtosatti@redhat.com>, qemu-devel@nongnu.org
Cc: Paolo Bonzini <pbonzini@redhat.com>, Andrey Korolyov <andrey@xdel.ru>, =?windows-1252?Q?Marcin_Gibu=C5=3F?= =?windows-1252?Q?a?= <m.gibula@beyond.pl>

Who are you pinging?


Alex

On 09.09.14 17:12, Marcelo Tosatti wrote:
> Ping?
> 
> On Fri, Sep 05, 2014 at 10:52:45AM -0300, Marcelo Tosatti wrote:
>> From: Alexander Graf <agraf@suse.de>
>>
>> When we migrate we ask the kernel about its current belief on what the guest
>> time would be. However, I've seen cases where the kvmclock guest structure
>> indicates a time more recent than the kvm returned time.
>>
>> To make sure we never go backwards, calculate what the guest would have seen as time at the point of migration and use that value instead of the kernel returned one when it's more recent.  
>> This bases the view of the kvmclock after migration on the 
>> same foundation in host as well as guest.
>>
>> Signed-off-by: Alexander Graf <agraf@suse.de>
>> Cc: qemu-stable@nongnu.org
>> Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
>> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> 
>