From 1ba59a44546797432d4c2fd2854281e3f4514d2d Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Fri, 6 Jan 2023 01:12:58 +0000 Subject: [PATCH] KVM: SVM: Always update local APIC on writes to logical dest register Update the vCPU's local (virtual) APIC on LDR writes even if the write "fails". The APIC needs to recalc the optimized logical map even if the LDR is invalid or zero, e.g. if the guest clears its LDR, the optimized map will be left as is and the vCPU will receive interrupts using its old LDR. Fixes: 18f40c53e10f ("svm: Add VMEXIT handlers for AVIC") Reviewed-by: Maxim Levitsky Signed-off-by: Sean Christopherson Message-Id: <20230106011306.85230-26-seanjc@google.com> Signed-off-by: Paolo Bonzini --- arch/x86/kvm/svm/avic.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c index 1fd473a..144e383 100644 --- a/arch/x86/kvm/svm/avic.c +++ b/arch/x86/kvm/svm/avic.c @@ -573,7 +573,7 @@ static void avic_invalidate_logical_id_entry(struct kvm_vcpu *vcpu) clear_bit(AVIC_LOGICAL_ID_ENTRY_VALID_BIT, (unsigned long *)entry); } -static int avic_handle_ldr_update(struct kvm_vcpu *vcpu) +static void avic_handle_ldr_update(struct kvm_vcpu *vcpu) { int ret = 0; struct vcpu_svm *svm = to_svm(vcpu); @@ -582,10 +582,10 @@ static int avic_handle_ldr_update(struct kvm_vcpu *vcpu) /* AVIC does not support LDR update for x2APIC */ if (apic_x2apic_mode(vcpu->arch.apic)) - return 0; + return; if (ldr == svm->ldr_reg) - return 0; + return; avic_invalidate_logical_id_entry(vcpu); @@ -594,8 +594,6 @@ static int avic_handle_ldr_update(struct kvm_vcpu *vcpu) if (!ret) svm->ldr_reg = ldr; - - return ret; } static void avic_handle_dfr_update(struct kvm_vcpu *vcpu) @@ -617,8 +615,7 @@ static int avic_unaccel_trap_write(struct kvm_vcpu *vcpu) switch (offset) { case APIC_LDR: - if (avic_handle_ldr_update(vcpu)) - return 0; + avic_handle_ldr_update(vcpu); break; case APIC_DFR: avic_handle_dfr_update(vcpu); -- 2.7.4