From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH v4] kvm: Use a bitmap for tracking used GSIs Date: Mon, 18 May 2009 17:46:09 +0300 Message-ID: <4A1174B1.9080201@redhat.com> References: <1242224129.9456.6.camel@lappy> <1242225238.9456.9.camel@lappy> <1242256055.9456.326.camel@lappy> <4A1077F9.8040604@redhat.com> <20090518111246.GB3037@redhat.com> <4A114849.604@redhat.com> <20090518121952.GA14327@redhat.com> <4A115590.6030500@redhat.com> <20090518134504.GB23296@redhat.com> <4A1168D2.7090709@redhat.com> <20090518144020.GB23940@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Alex Williamson , kvm@vger.kernel.org, sheng.yang@intel.com To: "Michael S. Tsirkin" Return-path: Received: from mx2.redhat.com ([66.187.237.31]:47275 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752680AbZEROqL (ORCPT ); Mon, 18 May 2009 10:46:11 -0400 In-Reply-To: <20090518144020.GB23940@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: Michael S. Tsirkin wrote: >> If it generates the interrupt after masking it in the msi-x entry, we'll >> see it. If it generates the interrupt before masking it, it may or may >> not receive the interrupt, even on real hardware. >> > > Yes but in the later case, real hardware must re-send the pending > interrupt after it is unmasked (that's the spec). We would just lose it. > That's a different matter. We need to buffer the interrupt pending bit, and a way for userspace to either query that buffer or have a conditional injection (inject_if_pending). -- error compiling committee.c: too many arguments to function