From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [net-next-2.6 PATCH 0/3 RFC] macvlan: MAC Address filtering support for passthru mode Date: Sun, 11 Sep 2011 22:03:25 +0300 Message-ID: <20110911190325.GC4740@redhat.com> References: <20110911094449.GF27096@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Sridhar Samudrala , netdev@vger.kernel.org, dragos.tatulea@gmail.com, arnd@arndb.de, dwang2@cisco.com, benve@cisco.com, kaber@trash.net, davem@davemloft.net, eric.dumazet@gmail.com, mchan@broadcom.com, kvm@vger.kernel.org To: Roopa Prabhu Return-path: Received: from mx1.redhat.com ([209.132.183.28]:5864 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760310Ab1IKTCi (ORCPT ); Sun, 11 Sep 2011 15:02:38 -0400 Content-Disposition: inline In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On Sun, Sep 11, 2011 at 06:18:01AM -0700, Roopa Prabhu wrote: > > > > On 9/11/11 2:44 AM, "Michael S. Tsirkin" wrote: > > >> > >> AFAIK, though it might maintain a single filter table space in hw, hw does > >> know which filter belongs to which VF. And the OS driver does not need to do > >> anything special. The VF driver exposes a VF netdev. And any uc/mc addresses > >> registered with a VF netdev are registered with the hw by the driver. And hw > >> will filter and send only pkts that the VF has expressed interest in. > >> > >> No special filter partitioning in hw is required. > >> > >> Thanks, > >> Roopa > > > > Yes, but what I mean is, if the size of the single filter table > > is limited, we need to decide how many addresses is > > each guest allowed. If we let one guest ask for > > as many as it wants, it can lock others out. > > Yes true. In these cases ie when the number of unicast addresses being > registered is more than it can handle, The VF driver will put the VF in > promiscuous mode (Or at least its supposed to do. I think all drivers do > that). > > > Thanks, > Roopa Right, so that works at least but likely performs worse than a hardware filter. So we better allocate it in some fair way, as a minimum. Maybe a way for the admin to control that allocation is useful. -- MST