From 24f7d36b824b65cf1a2db3db478059187b2a37b0 Mon Sep 17 00:00:00 2001 From: Yosry Ahmed Date: Tue, 24 Feb 2026 22:50:17 +0000 Subject: [PATCH] KVM: nSVM: Ensure AVIC is inhibited when restoring a vCPU to guest mode On nested VMRUN, KVM ensures AVIC is inhibited by requesting KVM_REQ_APICV_UPDATE, triggering a check of inhibit reasons, finding APICV_INHIBIT_REASON_NESTED, and disabling AVIC. However, when KVM_SET_NESTED_STATE is performed on a vCPU not in guest mode with AVIC enabled, KVM_REQ_APICV_UPDATE is not requested, and AVIC is not inhibited. Request KVM_REQ_APICV_UPDATE in the KVM_SET_NESTED_STATE path if AVIC is active, similar to the nested VMRUN path. Fixes: f44509f849fe ("KVM: x86: SVM: allow AVIC to co-exist with a nested guest running") Cc: stable@vger.kernel.org Signed-off-by: Yosry Ahmed Link: https://patch.msgid.link/20260224225017.3303870-1-yosry@kernel.org Signed-off-by: Sean Christopherson --- arch/x86/kvm/svm/nested.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index d5a8f5608f2d..3667f8ba5268 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -1928,6 +1928,9 @@ static int svm_set_nested_state(struct kvm_vcpu *vcpu, svm->nested.force_msr_bitmap_recalc = true; + if (kvm_vcpu_apicv_active(vcpu)) + kvm_make_request(KVM_REQ_APICV_UPDATE, vcpu); + kvm_make_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu); ret = 0; out_free: