From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from shards.monkeyblade.net (shards.monkeyblade.net [IPv6:2001:4f8:3:36:211:85ff:fe63:a549]) by lists.ozlabs.org (Postfix) with ESMTP id 7221B1A001E for ; Tue, 23 Jun 2015 23:27:41 +1000 (AEST) Date: Tue, 23 Jun 2015 06:39:26 -0700 (PDT) Message-Id: <20150623.063926.723221732046739833.davem@davemloft.net> To: alex.popov@linux.com Cc: pantelis.antoniou@gmail.com, vbordug@ru.mvista.com, christophe.leroy@c-s.fr, linuxppc-dev@lists.ozlabs.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 1/1] net: fs_enet: Fix NETIF_F_SG feature for Freescale MPC5121 From: David Miller In-Reply-To: <1434839566-31704-1-git-send-email-alex.popov@linux.com> References: <1434839566-31704-1-git-send-email-alex.popov@linux.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Alexander Popov Date: Sun, 21 Jun 2015 01:32:46 +0300 > Commit 4fc9b87bae25 ("net: fs_enet: Implement NETIF_F_SG feature") > brings a trouble to Freescale MPC512x: a kernel oops happens > during sending non-linear sk_buff with .data not aligned by 4. > > Log quotation: ... > The reason: > > MPC5121 FEC requires 4-byte alignment for TX data buffer and calls > tx_skb_align_workaround() for copying sk_buff with not aligned .data to a new > sk_buff with aligned one. But tx_skb_align_workaround() uses > skb_copy_from_linear_data() which doesn't work for non-linear sk_buff: > a new sk_buff has non-zero nr_frags and zero .data_len. > > So improve the condition of calling tx_skb_align_workaround() and use > skb_linearize() in it. > > Signed-off-by: Alexander Popov Applied, thanks.