From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758752AbbJ3Os3 (ORCPT ); Fri, 30 Oct 2015 10:48:29 -0400 Received: from mx1.redhat.com ([209.132.183.28]:40555 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751842AbbJ3Os2 (ORCPT ); Fri, 30 Oct 2015 10:48:28 -0400 From: =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= To: linux-kernel@vger.kernel.org Cc: kvm@vger.kernel.org, Paolo Bonzini , Yuki Shibuya Subject: [PATCH] KVM: x86: zero apic_arb_prio on reset Date: Fri, 30 Oct 2015 15:48:20 +0100 Message-Id: <1446216500-14267-1-git-send-email-rkrcmar@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- 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 1b02c44c7b8b..08655020417d 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -1924,6 +1924,8 @@ 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) -- 2.5.3