From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [Qemu-devel] [PATCH 0/5][RFC] virtio-net: MAC filtering Date: Fri, 09 Jan 2009 21:37:51 +0200 Message-ID: <4967A78F.7020006@redhat.com> References: <1231349852.7109.79.camel@lappy> <200901091127.32987.paul@codesourcery.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: qemu-devel@nongnu.org, Alex Williamson , kvm , Mark McLoughlin To: Paul Brook Return-path: Received: from mx2.redhat.com ([66.187.237.31]:60544 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752092AbZAITju (ORCPT ); Fri, 9 Jan 2009 14:39:50 -0500 In-Reply-To: <200901091127.32987.paul@codesourcery.com> Sender: kvm-owner@vger.kernel.org List-ID: Paul Brook wrote: >> A concern here is the growing size of the virtio-net I/O port space >> config. This series brings it up to 256 bytes with PCI resource >> rounding. The VLAN filter bitmap would increase that by another 512 >> bytes, making it 1kB and limiting us to something less than 64 such >> devices per guest. Is anyone worried? Should filter tables live in >> MMIO space for virtio devices? I'll send out the guest side patches for >> virtio-net in a separate thread. Thanks, >> > > This is one reason why IO ports are a reallybad idea. Use memory mapped > register spaces like any other sane system and you won't have a problem. > mmio is slower for virtualization. But I agree pio is baroque. Luckily we didn't implement the 768 pci slot thing, that wouldn't have flown (for yet another reason). -- I have a truly marvellous patch that fixes the bug which this signature is too narrow to contain.