From f8d8ac215919cf40d3b358846ed8e8e3a3683131 Mon Sep 17 00:00:00 2001 From: Suravee Suthikulpanit Date: Thu, 19 May 2022 05:27:06 -0500 Subject: [PATCH] KVM: x86: Warning APICv inconsistency only when vcpu APIC mode is valid When launching a VM with x2APIC and specify more than 255 vCPUs, the guest kernel can disable x2APIC (e.g. specify nox2apic kernel option). The VM fallbacks to xAPIC mode, and disable the vCPU ID 255 and greater. In this case, APICV is deactivated for the disabled vCPUs. However, the current APICv consistency warning does not account for this case, which results in a warning. Therefore, modify warning logic to report only when vCPU APIC mode is valid. Reviewed-by: Maxim Levitsky Signed-off-by: Suravee Suthikulpanit Message-Id: <20220519102709.24125-15-suravee.suthikulpanit@amd.com> Signed-off-by: Paolo Bonzini --- arch/x86/kvm/x86.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 47981e97d686..acd7ce1dcb9f 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -10477,7 +10477,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) * per-VM state, and responsing vCPUs must wait for the update * to complete before servicing KVM_REQ_APICV_UPDATE. */ - WARN_ON_ONCE(kvm_vcpu_apicv_activated(vcpu) != kvm_vcpu_apicv_active(vcpu)); + WARN_ON_ONCE((kvm_vcpu_apicv_activated(vcpu) != kvm_vcpu_apicv_active(vcpu)) && + (kvm_get_apic_mode(vcpu) != LAPIC_MODE_DISABLED)); exit_fastpath = static_call(kvm_x86_vcpu_run)(vcpu); if (likely(exit_fastpath != EXIT_FASTPATH_REENTER_GUEST))