KVM: x86: Unconditionally set l1tf_flush_l1d during vCPU load

Always set l1tf_flush_l1d during kvm_arch_vcpu_load() instead of setting
it only when the vCPU is being scheduled back in.  The flag is processed
only when VM-Enter is imminent, and KVM obviously needs to load the vCPU
before VM-Enter, so attempting to precisely set l1tf_flush_l1d provides no
meaningful value.  I.e. the flag _will_ be set either way, it's simply a
matter of when.

Acked-by: Kai Huang <kai.huang@intel.com>
Link: https://lore.kernel.org/r/20240522014013.1672962-6-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

Author: sean-jc

arch/x86/kvm/x86.c

@@ -5006,12 +5006,11 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 {
 	struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
 
-	if (vcpu->scheduled_out) {
-		vcpu->arch.l1tf_flush_l1d = true;
-		if (pmu->version && unlikely(pmu->event_count)) {
-			pmu->need_cleanup = true;
-			kvm_make_request(KVM_REQ_PMU, vcpu);
-		}
+	vcpu->arch.l1tf_flush_l1d = true;
+
+	if (vcpu->scheduled_out && pmu->version && pmu->event_count) {
+		pmu->need_cleanup = true;
+		kvm_make_request(KVM_REQ_PMU, vcpu);
 	}
 
 	/* Address WBINVD may be executed by guest */