From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Monjalon Subject: Re: [PATCH] i40e: fix the issue of wrongly reporting descriptor done Date: Sun, 02 Aug 2015 23:57:08 +0200 Message-ID: <1767019.fJcHX0QXRP@xps13> References: <1438207699-11848-1-git-send-email-helin.zhang@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Cc: dev@dpdk.org To: Helin Zhang Return-path: Received: from mail-wi0-f171.google.com (mail-wi0-f171.google.com [209.85.212.171]) by dpdk.org (Postfix) with ESMTP id 74033C41C for ; Sun, 2 Aug 2015 23:58:23 +0200 (CEST) Received: by wibud3 with SMTP id ud3so113940706wib.1 for ; Sun, 02 Aug 2015 14:58:23 -0700 (PDT) In-Reply-To: <1438207699-11848-1-git-send-email-helin.zhang@intel.com> List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" 2015-07-30 06:08, Helin Zhang: > Header buffer address for header split will be filled with the > physical address for DMA, which is actually not needed at all, > as header split hasn't been supported. Hardware requires the > least bit of header address which is 'Descriptor Done' bit when > write back should be set to 0 by driver. > The issue is that if the user wants to reserve an odd number of > bytes between the mbuf header and data buffer, the physical address > to be filled in the descriptor would happen to be odd. That means > the DD bit would be set to non-zero by driver. That will result in > reporting descriptor done wrongly. > > Signed-off-by: Helin Zhang Applied, thanks