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Date: Thu, 16 Apr 2009 17:58:36 -0300
From: Marcelo Tosatti <mtosatti@redhat.com>
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Subject: [Qemu-devel] Re: [patch 01/11] qemu: create helper for event
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To: Anthony Liguori <aliguori@us.ibm.com>
Cc: "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>

On Thu, Apr 16, 2009 at 03:53:04PM -0500, Anthony Liguori wrote:
>>      }
>>  }
>>   
>
> I always thought next_cpu was used here to cover an explicit race condition.
>
> If you're using TCG, and you get a single after running the loop, but  
> before assigning cpu_single_env, then you'll set the interrupt exit  
> request on the old CPU state.  You'll eventually exit I guess but you  
> potentially have to run through multiple VCPUs.
>
> I'd feel more comfortable if we preserved the behavior here that we had  
> before.

Right. Patch 7 reverts to the old behaviour.