From mboxrd@z Thu Jan 1 00:00:00 1970 From: Richard Cochran Subject: Re: [PATCH] net: dp83640: Fix tx timestamp overflow handling. Date: Wed, 20 Jan 2016 14:25:45 +0100 Message-ID: <20160120132545.GB2032@netboy> References: <1453285348-16022-1-git-send-email-manfred.rudigier@omicron.at> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: davem@davemloft.net, netdev@vger.kernel.org To: Manfred Rudigier Return-path: Received: from mail-wm0-f46.google.com ([74.125.82.46]:37616 "EHLO mail-wm0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751039AbcATNZt (ORCPT ); Wed, 20 Jan 2016 08:25:49 -0500 Received: by mail-wm0-f46.google.com with SMTP id n5so29208446wmn.0 for ; Wed, 20 Jan 2016 05:25:48 -0800 (PST) Content-Disposition: inline In-Reply-To: <1453285348-16022-1-git-send-email-manfred.rudigier@omicron.at> Sender: netdev-owner@vger.kernel.org List-ID: On Wed, Jan 20, 2016 at 11:22:28AM +0100, Manfred Rudigier wrote: > PHY status frames are not reliable, the PHY may not be able to send them > during heavy receive traffic. This overflow condition is signaled by the > PHY in the next status frame, but the driver did not make use of it. > Instead it always reported wrong tx timestamps to user space after an > overflow happened because it assigned newly received tx timestamps to old > packets in the queue. > > This commit fixes this issue by clearing the tx timestamp queue every time > an overflow happens, so that no timestamps are delivered for overflow > packets. This way time stamping will continue correctly after an overflow. Hi Manfred, Thanks for finding and fixing this bug. Dave, this patch should also go into stable. Acked-by: Richard Cochran