From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934250AbaDIShF (ORCPT ); Wed, 9 Apr 2014 14:37:05 -0400 Received: from shards.monkeyblade.net ([149.20.54.216]:57111 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933990AbaDIShB (ORCPT ); Wed, 9 Apr 2014 14:37:01 -0400 Date: Wed, 09 Apr 2014 14:36:55 -0400 (EDT) Message-Id: <20140409.143655.2112963679697366338.davem@davemloft.net> To: kys@microsoft.com Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, devel@linuxdriverproject.org, olaf@aepfle.de, apw@canonical.com, jasowang@redhat.com Subject: Re: [PATCH net 3/3] Drivers: net: hyperv: Address UDP checksum issues From: David Miller In-Reply-To: <4ae24ae5c6ea45c399e7be03c69dc442@BY2PR03MB299.namprd03.prod.outlook.com> References: <1396986371-12137-4-git-send-email-kys@microsoft.com> <20140409.130111.1002891296248446198.davem@davemloft.net> <4ae24ae5c6ea45c399e7be03c69dc442@BY2PR03MB299.namprd03.prod.outlook.com> X-Mailer: Mew version 6.5 on Emacs 24.1 / Mule 6.0 (HANACHIRUSATO) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: KY Srinivasan Date: Wed, 9 Apr 2014 18:08:47 +0000 > Thanks Dave. I will COW the SKB before changing the checksum > value. I do have a question though. I looked at a bunch of hardware > drivers and they modify the header information, specially checksum > field and I could not see where they had COWed the skb. I was > grepping for skb_cow in these drivers. Look for skb_cow_head(), for example, the tg3.c driver uses this.