[Qemu-devel] Re: [PATCH 4/4] KVM: Rework of guest debug state writing

[Jan Kiszka]

Marcelo Tosatti wrote:
> On Thu, Feb 04, 2010 at 08:00:26PM +0100, Jan Kiszka wrote:
>> Jan Kiszka wrote:
>>> Marcelo Tosatti wrote:
>>>> Unrelated to this problem, won't put_vcpu_events, which is executed 
>>>> after KVM_SET_GUEST_DEBUG, overwrite any queued debug exceptions?
>>> Good point, SET_GUEST_DEBUG should be last in the writeback for that reason.
>> Actually, we no longer need the exception injection via SET_GUEST_DEBUG
>> now that we have full access via vcpu_events. 
> 
>> So this needs a cleanup, and I'm afraid quite a few cases are broken
>> ATM with vcpu_events writeback overwriting the reinjected exceptions.
> 
> Don't see what you mean here. Can you be more explicit? What breakage?

SET_GUEST_DEBUG and SET_VCPU_EVENTS are mutually exclusive. If we have
the latter, don't use the former for exception injection anymore. And
this is broken already without any of my patches applied, that was my
point. Will work on this soon.

Jan

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