From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH v9 1/2] kvm: Use a reserved IRQ source ID for irqfd Date: Wed, 05 Sep 2012 17:59:46 +0300 Message-ID: <504768E2.3020706@redhat.com> 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> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Alex Williamson , gleb@redhat.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org To: "Michael S. Tsirkin" Return-path: In-Reply-To: <20120905145153.GA11048@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.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