RE: [04/17] [PATCH] Add kvm arch-specific core code for kvm/ia64.-V8

["Zhang, Xiantao" <xiantao.zhang@xxxxxxxxx>]

Carsten Otte wrote:
> Zhang, Xiantao wrote:
>> Hi, Carsten
>>      Why do you think it is racy?  In this function,
>> target_vcpu->arch.launched should be set to 1 for the first run, and
>> keep its value all the time.  Except the first IPI to wake up the
>> vcpu, all IPIs received by target vcpu should go into "else"
>> condition. So you mean the race condition exist in "else"  code ?
> For example to lock against destroying that vcpu. Or, the waitqueue
> may become active after if (waitqueue_active()) and before
> wake_up_interruptible(). In that case, the target vcpu might sleep and
> not get waken up by the ipi.
I don't think it may cause issue, because the target vcpu at least can
be waken up by the timer interrupt. 

But as you said,  x86 side also have the same race issue ? 

Xiantao
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