Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753313AbcJNICX (ORCPT ); Fri, 14 Oct 2016 04:02:23 -0400 Received: from mail-lf0-f66.google.com ([209.85.215.66]:32816 "EHLO mail-lf0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751025AbcJNICP (ORCPT ); Fri, 14 Oct 2016 04:02:15 -0400 Subject: Re: [PATCH 3/3] KVM: x86: do not scan IRR twice on APICv vmentry To: Yang Zhang , linux-kernel@vger.kernel.org, kvm@vger.kernel.org References: <1475011213-34225-1-git-send-email-pbonzini@redhat.com> <1475011213-34225-4-git-send-email-pbonzini@redhat.com> <30768946-c4f6-f9bd-5495-2a3adefffc69@gmail.com> Cc: feng.wu@intel.com, mst@redhat.com, rkrcmar@redhat.com From: Paolo Bonzini Message-ID: <993cab93-393e-b850-9bb5-db21c98f03e9@redhat.com> Date: Fri, 14 Oct 2016 09:45:57 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.3.0 MIME-Version: 1.0 In-Reply-To: <30768946-c4f6-f9bd-5495-2a3adefffc69@gmail.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 632 Lines: 22 On 14/10/2016 09:32, Yang Zhang wrote: >> >> -void __kvm_apic_update_irr(u32 *pir, void *regs) >> +int __kvm_apic_update_irr(u32 *pir, void *regs) >> { >> - u32 i, pir_val; >> + u32 i, vec; >> + u32 pir_val, irr_val; >> + int max_irr = -1; >> >> - for (i = 0; i <= 7; i++) { >> + for (i = vec = 0; i <= 7; i++, vec += 32) { > > how about ignore the first 32 vectors since they cannot be used as > normal interrupt except nmi interrupt which is special handled. I think that, while they should not be used as normal interrupts, there's nothing that prevents you from misusing them as normal interrupts. Paolo