From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753631Ab2IEO7u (ORCPT ); Wed, 5 Sep 2012 10:59:50 -0400 Received: from mx1.redhat.com ([209.132.183.28]:50987 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751489Ab2IEO7s (ORCPT ); Wed, 5 Sep 2012 10:59:48 -0400 Message-ID: <504768E2.3020706@redhat.com> Date: Wed, 05 Sep 2012 17:59:46 +0300 From: Avi Kivity User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:14.0) Gecko/20120717 Thunderbird/14.0 MIME-Version: 1.0 To: "Michael S. Tsirkin" CC: Alex Williamson , gleb@redhat.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v9 1/2] kvm: Use a reserved IRQ source ID for irqfd References: <20120821190800.24958.74812.stgit@bling.home> <20120821192903.24958.90138.stgit@bling.home> <20120821195813.GD9027@redhat.com> <1345579579.29292.67.camel@ul30vt.home> <20120821204125.GF9027@redhat.com> <1345583694.29292.91.camel@ul30vt.home> <20120822004138.GM9027@redhat.com> <5047633F.9020405@redhat.com> <20120905145153.GA11048@redhat.com> In-Reply-To: <20120905145153.GA11048@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/05/2012 05:51 PM, Michael S. Tsirkin wrote: > On Wed, Sep 05, 2012 at 05:35:43PM +0300, Avi Kivity wrote: >> On 08/22/2012 03:41 AM, Michael S. Tsirkin wrote: >> >> >> >> I assumed you were pointing out the level vs edge interaction. If we >> >> call that a userspace bug, I can just drop this. Thanks, >> >> >> >> Alex >> > >> > level is userspace bug I think :) >> >> I don't see how it's a bug. Suppose we have a vfio device that shares a >> gsi with an emulated device. The emulated device naturally uses >> KVM_IRQ_LINE (it has no need to re-sample on ADN), while vfio naturally >> has to use irqfd. > > Absolutely. But vfio needs to use irqfd with the new flag. > Using existing irqfd for level is a bug. I see we're not reusing this irq source id for level irqfd. But I think we should, there's no need for per-gsi irq source id. Plus I'd like to fix the theoretical bug even if it doesn't bite in practice. -- error compiling committee.c: too many arguments to function