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Date: Mon, 17 Sep 2012 20:25:55 +0200
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Subject: Re: [Qemu-devel] [RFC PATCH 04/10] tcg: change cpu_restore_state to
	return void
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To: Peter Maydell <peter.maydell@linaro.org>
Cc: qemu-devel@nongnu.org

Il 17/09/2012 19:20, Peter Maydell ha scritto:
>> > Couldn't that mean simply that the tb for instance wasn't mapped
>> > anywhere?  That's the KVM case, at least.
> Hmm. For TCG there are certainly some cases where failure to
> cpu_restore_state() means that the current CPU state is now broken;
> that should be fatal (and I'm not sure there are any cases where
> failure is OK. I think calls are generally protected by
> checking that tb_find_pc() returned non-NULL, so we shouldn't
> be trying to restore state unless we really were in the middle
> of a TB that we know about and can translate.)
> 
> I'm not sure what the TB concept means for KVM -- after all KVM
> doesn't do any translation...

Nothing, but in some cases cpu_restore_state() is called from exception
handling helpers or something like that.  My knowledge is spotty.

Paolo