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Subject: Re: [PATCH v11 6/6] target-arm: kvm64: Handle SError interrupt for
 the guest OS
To: Peter Maydell <peter.maydell@linaro.org>
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On 2017/9/13 18:52, Peter Maydell wrote:
> This question seems to be not really related to the review
> comment that it is responding to.
> 
> (1) If the host does not support notifying us about
> errors, then there is clearly nothing to do in this
> code, because we will never get a notification.
> 
> (2) If the host does support notifying us about errors,
> but we choose not to expose RAS to the guest, then
> there's not much to do either. We probably just want
> to take whatever the default behaviour is for any
> application when it touches memory that's bad.
> We definitely don't want to tell the guest anything.
> 
> (3) If the host supports notification, and we choose
> to expose RAS to the guest, then we need to do
> whatever we have to do to notify the guest.
> 
> If we're in this signal handler and also
> arm_feature(env, ARM_FEATURE_RAS) is false then that
> is case (2), and my point is that doing anything with
> the guest 'syndrome' value looks like the wrong thing.

Peter,
  your explanation is clear. OK, understand, thanks.