From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcelo Tosatti Subject: Re: [PATCH v3 1/8] Do not call ack notifiers on PIC reset. Date: Thu, 13 Aug 2009 06:11:05 -0300 Message-ID: <20090813091105.GA17022@amt.cnet> References: <1250079442-5163-1-git-send-email-gleb@redhat.com> <1250079442-5163-2-git-send-email-gleb@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: avi@redhat.com, kvm@vger.kernel.org To: Gleb Natapov Return-path: Received: from mx2.redhat.com ([66.187.237.31]:34536 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753647AbZHMJNt (ORCPT ); Thu, 13 Aug 2009 05:13:49 -0400 Received: from int-mx2.corp.redhat.com (int-mx2.corp.redhat.com [172.16.27.26]) by mx2.redhat.com (8.13.8/8.13.8) with ESMTP id n7D9Do71003670 for ; Thu, 13 Aug 2009 05:13:50 -0400 Content-Disposition: inline In-Reply-To: <1250079442-5163-2-git-send-email-gleb@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On Wed, Aug 12, 2009 at 03:17:15PM +0300, Gleb Natapov wrote: > For device assigned it may cause host hang since ack notifier callback > enables host interrupt and guest not necessary cleared interrupt > condition in an assigned device. For PIT we should not call ack notifier > here since interrupt was not acked by a guest and should be redelivered. > > Signed-off-by: Gleb Natapov > --- > arch/x86/kvm/i8259.c | 16 ---------------- > 1 files changed, 0 insertions(+), 16 deletions(-) > > diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c > index 01f1516..eb2b8b7 100644 > --- a/arch/x86/kvm/i8259.c > +++ b/arch/x86/kvm/i8259.c > @@ -225,22 +225,6 @@ int kvm_pic_read_irq(struct kvm *kvm) > > void kvm_pic_reset(struct kvm_kpic_state *s) > { > - int irq, irqbase, n; > - struct kvm *kvm = s->pics_state->irq_request_opaque; > - struct kvm_vcpu *vcpu0 = kvm->bsp_vcpu; > - > - if (s == &s->pics_state->pics[0]) > - irqbase = 0; > - else > - irqbase = 8; > - > - for (irq = 0; irq < PIC_NUM_PINS/2; irq++) { > - if (vcpu0 && kvm_apic_accept_pic_intr(vcpu0)) > - if (s->irr & (1 << irq) || s->isr & (1 << irq)) { > - n = irq + irqbase; > - kvm_notify_acked_irq(kvm, SELECT_PIC(n), n); > - } > - } > s->last_irr = 0; > s->irr = 0; > s->imr = 0; > -- > 1.6.3.3 This used to be necessary to clear pending state from i8254.c "irq_acked" logic. I think it'll break it.