Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753255AbZA0Evk (ORCPT ); Mon, 26 Jan 2009 23:51:40 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751759AbZA0Ev1 (ORCPT ); Mon, 26 Jan 2009 23:51:27 -0500 Received: from ozlabs.org ([203.10.76.45]:59281 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751372AbZA0Ev1 (ORCPT ); Mon, 26 Jan 2009 23:51:27 -0500 From: Rusty Russell To: Ira Snyder Subject: Re: [PATCH] virtio_net: use correct accessors for scatterlists Date: Tue, 27 Jan 2009 15:21:19 +1030 User-Agent: KMail/1.10.3 (Linux/2.6.27-9-generic; KDE/4.1.3; i686; ; ) Cc: linux-kernel@vger.kernel.org, Mark McLoughlin , netdev@vger.kernel.org, "David S. Miller" References: <20090124001053.GA20156@ovro.caltech.edu> In-Reply-To: <20090124001053.GA20156@ovro.caltech.edu> MIME-Version: 1.0 Content-Disposition: inline Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <200901271521.19616.rusty@rustcorp.com.au> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2198 Lines: 62 On Saturday 24 January 2009 10:40:53 Ira Snyder wrote: > Without this fix, virtio_net makes incorrect usage of scatterlists. It sets > the end of the scatterlist chain after the first element, despite the fact > that more entries come after it. > > If you try to run dma_map_sg() on one of the scatterlists given to you by > add_buf(), you will get a null pointer oops. > > Signed-off-by: Ira W. Snyder Thanks, this should go in 2.6.29. Dave? Cheers, Rusty. Subject: virtio_net: use correct accessors for scatterlists Date: Fri, 23 Jan 2009 16:10:53 -0800 From: Ira Snyder Without this fix, virtio_net makes incorrect usage of scatterlists. It sets the end of the scatterlist chain after the first element, despite the fact that more entries come after it. If you try to run dma_map_sg() on one of the scatterlists given to you by add_buf(), you will get a null pointer oops. Signed-off-by: Ira W. Snyder Signed-off-by: Rusty Russell --- drivers/net/virtio_net.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 43f6523..67ea2cf 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -286,7 +286,7 @@ static void try_fill_recv_maxbufs(struct virtnet_info *vi) skb_put(skb, MAX_PACKET_LEN); hdr = skb_vnet_hdr(skb); - sg_init_one(sg, hdr, sizeof(*hdr)); + sg_set_buf(sg, hdr, sizeof(*hdr)); if (vi->big_packets) { for (i = 0; i < MAX_SKB_FRAGS; i++) { @@ -487,9 +487,9 @@ static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb) /* Encode metadata header at front. */ if (vi->mergeable_rx_bufs) - sg_init_one(sg, mhdr, sizeof(*mhdr)); + sg_set_buf(sg, mhdr, sizeof(*mhdr)); else - sg_init_one(sg, hdr, sizeof(*hdr)); + sg_set_buf(sg, hdr, sizeof(*hdr)); num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/