Messages in this thread | | | From | "Kang, Luwei" <> | Subject | RE: [PATCH] KVM: x86: Sync the pending Posted-Interrupts | Date | Tue, 29 Jan 2019 09:32:36 +0000 |
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> > However, you should at least change the comment in vcpu_enter_guest to > > mention "before reading PIR" instead of "before reading PIR.ON". > > Will do that. I think the "checking PIR.ON" should be PID.ON. I will fix it. > Hi Paolo, I reconsidered the comment in vcpu_enter_guest() and think it may don't need to change. The original comment as below: * 2) For APICv, we should set ->mode before checking PIR.ON. This * pairs with the memory barrier implicit in pi_test_and_set_on * (see vmx_deliver_posted_interrupt).
I think "before checking PIR.ON" is mean "before checking PID.PIR and PID.ON". Because there indeed have this two flag check in vmx_deliver_posted_interrupt() function. If PID.ON is already Set at the time of hardware posting an interrupt to PIR field, notification event is not generated (from VT-d spec 9.12).
Thanks, Luwei Kang
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