From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anthony Liguori Subject: Re: [Qemu-devel] [PATCH 0/5][RFC] virtio-net: MAC filtering Date: Fri, 09 Jan 2009 13:41:02 -0600 Message-ID: <4967A84E.9080908@codemonkey.ws> 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 fg-out-1718.google.com ([72.14.220.155]:19605 "EHLO fg-out-1718.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751521AbZAITlN (ORCPT ); Fri, 9 Jan 2009 14:41:13 -0500 Received: by fg-out-1718.google.com with SMTP id 19so3507865fgg.17 for ; Fri, 09 Jan 2009 11:41:12 -0800 (PST) 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. > IO ports are much faster for notification than MMIO in KVM which is why the space is currently IO ports. It was never meant to hold very large amounts of data. Regards, Anthony Liguori > Paul > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >