diff options
| author | Sean Christopherson <seanjc@google.com> | 2026-02-03 11:07:09 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-03-19 16:08:24 +0100 |
| commit | c513bbd7da534f964d975086394cb3d65a34e574 (patch) | |
| tree | 10688aaa234111548258007cd2b89a291bb0a53c /arch/x86 | |
| parent | b058c30cdf7d5921a67b35da9cbc3944f7c5bb8a (diff) | |
KVM: SVM: Initialize AVIC VMCB fields if AVIC is enabled with in-kernel APIC
commit 3989a6d036c8ec82c0de3614bed23a1dacd45de5 upstream.
Initialize all per-vCPU AVIC control fields in the VMCB if AVIC is enabled
in KVM and the VM has an in-kernel local APIC, i.e. if it's _possible_ the
vCPU could activate AVIC at any point in its lifecycle. Configuring the
VMCB if and only if AVIC is active "works" purely because of optimizations
in kvm_create_lapic() to speculatively set apicv_active if AVIC is enabled
*and* to defer updates until the first KVM_RUN. In quotes because KVM
likely won't do the right thing if kvm_apicv_activated() is false, i.e. if
a vCPU is created while APICv is inhibited at the VM level for whatever
reason. E.g. if the inhibit is *removed* before KVM_REQ_APICV_UPDATE is
handled in KVM_RUN, then __kvm_vcpu_update_apicv() will elide calls to
vendor code due to seeing "apicv_active == activate".
Cleaning up the initialization code will also allow fixing a bug where KVM
incorrectly leaves CR8 interception enabled when AVIC is activated without
creating a mess with respect to whether AVIC is activated or not.
Cc: stable@vger.kernel.org
Fixes: 67034bb9dd5e ("KVM: SVM: Add irqchip_split() checks before enabling AVIC")
Fixes: 6c3e4422dd20 ("svm: Add support for dynamic APICv")
Reviewed-by: Naveen N Rao (AMD) <naveen@kernel.org>
Reviewed-by: Jim Mattson <jmattson@google.com>
Link: https://patch.msgid.link/20260203190711.458413-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kvm/svm/avic.c | 2 | ||||
| -rw-r--r-- | arch/x86/kvm/svm/svm.c | 2 |
2 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c index fef00546c885..5578e76d5f38 100644 --- a/arch/x86/kvm/svm/avic.c +++ b/arch/x86/kvm/svm/avic.c @@ -321,7 +321,7 @@ void avic_init_vmcb(struct vcpu_svm *svm, struct vmcb *vmcb) vmcb->control.avic_physical_id = __sme_set(__pa(kvm_svm->avic_physical_id_table)); vmcb->control.avic_vapic_bar = APIC_DEFAULT_PHYS_BASE; - if (kvm_apicv_activated(svm->vcpu.kvm)) + if (kvm_vcpu_apicv_active(&svm->vcpu)) avic_activate_vmcb(svm); else avic_deactivate_vmcb(svm); diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index eed104207a11..79335c12586c 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -1141,7 +1141,7 @@ static void init_vmcb(struct kvm_vcpu *vcpu, bool init_event) svm_clr_intercept(svm, INTERCEPT_PAUSE); } - if (kvm_vcpu_apicv_active(vcpu)) + if (enable_apicv && irqchip_in_kernel(vcpu->kvm)) avic_init_vmcb(svm, vmcb); if (vnmi) |