Re: [PATCH] KVM: SVM: unconditionally wake up VCPU on IOMMU interrupt

Radim Krčmář
2017-10-10T19:17:17Z

2017-10-10 12:57+0200, Paolo Bonzini:
> Checking the mode is unnecessary, and is done without a memory barrier
> separating the LAPIC write from the vcpu->mode read; in addition,
> kvm_vcpu_wake_up is already doing a check for waiters on the wait queue
> that has the same effect.
>
> In practice it's safe because spin_lock has full-barrier semantics on x86,
> but don't be too clever.
>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---

Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>