Re: [PATCH v2 37/43] KVM: SVM: Unconditionally mark AVIC as running on vCPU load (with APICv)
Paolo Bonzini <[email protected]>
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On 25/10/21 17:48, Sean Christopherson wrote:
> On Mon, Oct 25, 2021, Paolo Bonzini wrote:
>> On 09/10/21 04:12, Sean Christopherson wrote:
>>> + /* TODO: Document why the unblocking path checks for updates. */
>>
>> Is that a riddle or what? :)
>
> Yes? I haven't been able to figure out why the unblocking path explicitly
> checks and handles an APICv update.
>
Challenge accepted. In the original code, it was because without it
avic_vcpu_load would do nothing, and nothing would update the IS_RUNNING
flag.
It shouldn't be necessary anymore since commit df7e4827c549 ("KVM: SVM:
call avic_vcpu_load/avic_vcpu_put when enabling/disabling AVIC",
2021-08-20), where svm_refresh_apicv_exec_ctrl takes care of the
avic_vcpu_load on the next VMRUN.
Paolo