From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ichiro Suzuki Subject: Re: Question about VLAN + checksum offloading Date: Tue, 20 May 2008 12:19:48 +0900 Message-ID: <1211253588.9823.2.camel@localhost.localdomain> References: <1210924374.5136.94.camel@localhost.localdomain> <4831BC4D.7000601@trash.net> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: "Waskiewicz Jr, Peter P" , netdev@vger.kernel.org, Naohiro Ooiwa To: Patrick McHardy Return-path: Received: from ns.miraclelinux.com ([219.118.163.66]:49819 "EHLO mail.miraclelinux.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754986AbYETDTu (ORCPT ); Mon, 19 May 2008 23:19:50 -0400 In-Reply-To: <4831BC4D.7000601@trash.net> Sender: netdev-owner@vger.kernel.org List-ID: Thank you, PJ and Patrick. I'll revisit the code after VLAN patches are posted. ---------------------------------------------- Ichiro Suzuki Miracle Linux Corp., Advanced Technology Group ---------------------------------------------- On Mon, 2008-05-19 at 19:43 +0200, Patrick McHardy wrote: > Waskiewicz Jr, Peter P wrote: > >> o If so, is there any mechanism to propagate > >> real_dev->features flags in vlan.c? > > > > There isn't an explicit way. I had written patches into e1000, igb, > > e1000e, and ixgbe to propogate the VLAN flags within the driver when the > > VLAN device was created. The trick though is if you remove a feature > > flag with ethtool, say checksum offload, on your main device, you > > probably should turn it off on your VLAN devices. Patrick McHardy > > pointed me at netdev_feature_change() to use within the driver. I'll > > admit I haven't had the time to fix my drivers to use this call, but it > > certainly looks like the way to go. Please see the (middle) of the > > thread here: http://marc.info/?l=linux-netdev&m=120878809806631&w=2 > > > >> o If such mechanism doesn't exist, is my patch reasonable? > > > > I would say yes, halfway. The issue is you probably want to remove the > > feature flag from the VLAN device if you removed the flag from the > > parent device as well. > > > Yes, it should use the same mechanism as suggested for the > VLAN accel feature. And it should be limited to features > that are known to work, not just blindly copy everything. > > I will be catching up with the VLAN patches posted recently > sometime next week. I guess I can then also add a patch for > feature propagation myself if you don't beat me to it :) > >