diff options
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kvm/svm/svm.c | 2 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 20 |
2 files changed, 20 insertions, 2 deletions
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index cee4915d2ce3..a2a4e9b42750 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -3864,8 +3864,6 @@ static __no_kcsan fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu) pre_svm_run(vcpu); - WARN_ON_ONCE(kvm_apicv_activated(vcpu->kvm) != kvm_vcpu_apicv_active(vcpu)); - sync_lapic_to_cr8(vcpu); if (unlikely(svm->asid != svm->vmcb->control.asid)) { diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 3a74540caca2..a09365ecdf01 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -9481,6 +9481,18 @@ void __kvm_request_apicv_update(struct kvm *kvm, bool activate, ulong bit) if (!!old != !!new) { trace_kvm_apicv_update_request(activate, bit); + /* + * Kick all vCPUs before setting apicv_inhibit_reasons to avoid + * false positives in the sanity check WARN in svm_vcpu_run(). + * This task will wait for all vCPUs to ack the kick IRQ before + * updating apicv_inhibit_reasons, and all other vCPUs will + * block on acquiring apicv_update_lock so that vCPUs can't + * redo svm_vcpu_run() without seeing the new inhibit state. + * + * Note, holding apicv_update_lock and taking it in the read + * side (handling the request) also prevents other vCPUs from + * servicing the request with a stale apicv_inhibit_reasons. + */ kvm_make_all_cpus_request(kvm, KVM_REQ_APICV_UPDATE); kvm->arch.apicv_inhibit_reasons = new; if (new) { @@ -9815,6 +9827,14 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) } for (;;) { + /* + * Assert that vCPU vs. VM APICv state is consistent. An APICv + * update must kick and wait for all vCPUs before toggling the + * per-VM state, and responsing vCPUs must wait for the update + * to complete before servicing KVM_REQ_APICV_UPDATE. + */ + WARN_ON_ONCE(kvm_apicv_activated(vcpu->kvm) != kvm_vcpu_apicv_active(vcpu)); + exit_fastpath = static_call(kvm_x86_run)(vcpu); if (likely(exit_fastpath != EXIT_FASTPATH_REENTER_GUEST)) break; |