From 0669a51015c58b1f036030743a0c0781eb63867f Mon Sep 17 00:00:00 2001 From: =?utf8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= Date: Fri, 30 Oct 2015 15:48:20 +0100 Subject: [PATCH] KVM: x86: zero apic_arb_prio on reset MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit BSP doesn't get INIT so its apic_arb_prio isn't zeroed after reboot. BSP won't get lowest priority interrupts until other VCPUs get enough interrupts to match their pre-reboot apic_arb_prio. That behavior doesn't fit into KVM's round-robin-like interpretation of lowest priority delivery ... userspace should KVM_SET_LAPIC on reset, so just zero apic_arb_prio there. Reported-by: Yuki Shibuya Signed-off-by: Radim Krčmář Signed-off-by: Paolo Bonzini --- arch/x86/kvm/lapic.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 168b8759bd73..ecd4ea1d28a8 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -1918,6 +1918,8 @@ void kvm_apic_post_state_restore(struct kvm_vcpu *vcpu, kvm_make_request(KVM_REQ_EVENT, vcpu); if (ioapic_in_kernel(vcpu->kvm)) kvm_rtc_eoi_tracking_restore_one(vcpu); + + vcpu->arch.apic_arb_prio = 0; } void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu) -- 2.20.1