From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1LLNCv-0003x6-UK for qemu-devel@nongnu.org; Fri, 09 Jan 2009 14:39:49 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1LLNCu-0003ur-C2 for qemu-devel@nongnu.org; Fri, 09 Jan 2009 14:39:49 -0500 Received: from [199.232.76.173] (port=34146 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1LLNCu-0003uf-4F for qemu-devel@nongnu.org; Fri, 09 Jan 2009 14:39:48 -0500 Received: from mx2.redhat.com ([66.187.237.31]:52302) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1LLNCs-0004hz-JM for qemu-devel@nongnu.org; Fri, 09 Jan 2009 14:39:47 -0500 Message-ID: <4967A78F.7020006@redhat.com> Date: Fri, 09 Jan 2009 21:37:51 +0200 From: Avi Kivity MIME-Version: 1.0 Subject: Re: [Qemu-devel] [PATCH 0/5][RFC] virtio-net: MAC filtering References: <1231349852.7109.79.camel@lappy> <200901091127.32987.paul@codesourcery.com> In-Reply-To: <200901091127.32987.paul@codesourcery.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paul Brook Cc: Mark McLoughlin , qemu-devel@nongnu.org, Alex Williamson , kvm 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.