From mboxrd@z Thu Jan 1 00:00:00 1970 From: Claudiu Manoil Subject: Re: [PATCH] Documentation: document the gianfar tx vlan offload issue Date: Fri, 4 Apr 2014 10:07:05 +0300 Message-ID: <533E5A19.6060701@freescale.com> References: <1396580685-17156-1-git-send-email-roy.qing.li@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Cc: To: , Return-path: Received: from tx2ehsobe005.messaging.microsoft.com ([65.55.88.15]:55715 "EHLO tx2outboundpool.messaging.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752050AbaDDHHO (ORCPT ); Fri, 4 Apr 2014 03:07:14 -0400 In-Reply-To: <1396580685-17156-1-git-send-email-roy.qing.li@gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: On 4/4/2014 6:04 AM, roy.qing.li@gmail.com wrote: > From: Li RongQing > > The commit b852b72087[gianfar: fix bug caused by 87c288c6e9] and e2c53be223 > [gianfar: fix default tx vlan offload feature flag] disabled tx vlan offload > from dev->feature, since enabling vlan tag insertion leads to unusable > connections on some configurations. > > But this feature is in dev->hw_feature still, and a user can enable it by > "ethtool", so document the tx vlan offload issue. > > Signed-off-by: Li RongQing > Signed-off-by: Zhu Yanjun > Cc: Claudiu Manoil > --- > Documentation/networking/gianfar.txt | 12 ++++++++++++ > 1 file changed, 12 insertions(+) > > diff --git a/Documentation/networking/gianfar.txt b/Documentation/networking/gianfar.txt > index ad474ea..2d3dbe6 100644 > --- a/Documentation/networking/gianfar.txt > +++ b/Documentation/networking/gianfar.txt > @@ -51,6 +51,18 @@ configuring VLANs. The gianfar driver supports hardware insertion and > extraction of VLAN headers, but not filtering. Filtering will be > done by the kernel. > > +But if tx vlan tag hardware insertion is enabled, and a vlan-device is > +created, the physical device which vlan device is on will be unable to > +work, like: > + > + $ethtool -K eth0 tx-vlan-stag-hw-insert on > + $ifconfig eth0 192.168.1.13/24 up > + > + $vconfig add eth0 4091 > + $ifconfig eth0.4091 10.1.1.13/24 up > +eth0.4091 can work, but eth0 can not work, since eth0 sends the insane > +packets out. > + I don't really like this, this is hardly a technical explanation. ("insane packets"?) Please have a look at the HW reference manual. There you have the description of the VLAN extraction feature (see VLEX). Regards, Claudiu