From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6EA29C65C30 for ; Sat, 6 Oct 2018 11:27:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 17DF82147D for ; Sat, 6 Oct 2018 11:27:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 17DF82147D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=codethink.co.uk Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727791AbeJFSaY (ORCPT ); Sat, 6 Oct 2018 14:30:24 -0400 Received: from imap1.codethink.co.uk ([176.9.8.82]:51644 "EHLO imap1.codethink.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727161AbeJFSaY (ORCPT ); Sat, 6 Oct 2018 14:30:24 -0400 Received: from [192.168.122.135] (helo=_) by imap1.codethink.co.uk with esmtpsa (Exim 4.84_2 #1 (Debian)) id 1g8kk3-0005v1-Dl; Sat, 06 Oct 2018 12:27:27 +0100 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Sat, 06 Oct 2018 12:27:27 +0100 From: Ben Dooks To: David Miller Cc: netdev@vger.kernel.org, David.Laight@aculab.com, oneukum@suse.com, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kernel@lists.codethink.co.uk Subject: Re: [PATCH] usbnet: smsc95xx: simplify tx_fixup code In-Reply-To: <20181005.142412.601607260441380535.davem@davemloft.net> References: <59988ed22559410881addfecf58335eb@AcuMS.aculab.com> <20181002165602.21033-1-ben.dooks@codethink.co.uk> <20181005.142412.601607260441380535.davem@davemloft.net> Message-ID: <40033993674bb8b5ef33ac33f28f3aff@codethink.co.uk> X-Sender: ben.dooks@codethink.co.uk User-Agent: Roundcube Webmail/1.1.5 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2018-10-05 22:24, David Miller wrote: > From: Ben Dooks > Date: Tue, 2 Oct 2018 17:56:02 +0100 > >> - memcpy(skb->data, &tx_cmd_a, 4); >> + ptr = skb_push(skb, 8); >> + tx_cmd_a = cpu_to_le32(tx_cmd_a); >> + tx_cmd_b = cpu_to_le32(tx_cmd_b); >> + memcpy(ptr, &tx_cmd_a, 4); >> + memcpy(ptr+4, &tx_cmd_b, 4); > > Even a memcpy() through a void pointer does not guarantee that gcc will > not emit word sized loads and stores. > > You must use the get_unaligned()/put_unaligned() facilities to do this > properly. Thanks, got a new version of the series just being tested with this. Should it go into the original, or as a separate change? > > I also agree that making a proper type and structure instead of using > a void pointer would be better. From mboxrd@z Thu Jan 1 00:00:00 1970 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Subject: usbnet: smsc95xx: simplify tx_fixup code From: Ben Dooks Message-Id: <40033993674bb8b5ef33ac33f28f3aff@codethink.co.uk> Date: Sat, 06 Oct 2018 12:27:27 +0100 To: David Miller Cc: netdev@vger.kernel.org, David.Laight@aculab.com, oneukum@suse.com, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kernel@lists.codethink.co.uk List-ID: T24gMjAxOC0xMC0wNSAyMjoyNCwgRGF2aWQgTWlsbGVyIHdyb3RlOgo+IEZyb206IEJlbiBEb29r cyA8YmVuLmRvb2tzQGNvZGV0aGluay5jby51az4KPiBEYXRlOiBUdWUsICAyIE9jdCAyMDE4IDE3 OjU2OjAyICswMTAwCj4gCj4+IC0JbWVtY3B5KHNrYi0+ZGF0YSwgJnR4X2NtZF9hLCA0KTsKPj4g KwlwdHIgPSBza2JfcHVzaChza2IsIDgpOwo+PiArCXR4X2NtZF9hID0gY3B1X3RvX2xlMzIodHhf Y21kX2EpOwo+PiArCXR4X2NtZF9iID0gY3B1X3RvX2xlMzIodHhfY21kX2IpOwo+PiArCW1lbWNw eShwdHIsICZ0eF9jbWRfYSwgNCk7Cj4+ICsJbWVtY3B5KHB0cis0LCAmdHhfY21kX2IsIDQpOwo+ IAo+IEV2ZW4gYSBtZW1jcHkoKSB0aHJvdWdoIGEgdm9pZCBwb2ludGVyIGRvZXMgbm90IGd1YXJh bnRlZSB0aGF0IGdjYyB3aWxsCj4gbm90IGVtaXQgd29yZCBzaXplZCBsb2FkcyBhbmQgc3RvcmVz Lgo+IAo+IFlvdSBtdXN0IHVzZSB0aGUgZ2V0X3VuYWxpZ25lZCgpL3B1dF91bmFsaWduZWQoKSBm YWNpbGl0aWVzIHRvIGRvIHRoaXMKPiBwcm9wZXJseS4KClRoYW5rcywgZ290IGEgbmV3IHZlcnNp b24gb2YgdGhlIHNlcmllcyBqdXN0IGJlaW5nIHRlc3RlZCB3aXRoIHRoaXMuClNob3VsZCBpdCBn byBpbnRvIHRoZSBvcmlnaW5hbCwgb3IgYXMgYSBzZXBhcmF0ZSBjaGFuZ2U/Cgo+IAo+IEkgYWxz byBhZ3JlZSB0aGF0IG1ha2luZyBhIHByb3BlciB0eXBlIGFuZCBzdHJ1Y3R1cmUgaW5zdGVhZCBv ZiB1c2luZwo+IGEgdm9pZCBwb2ludGVyIHdvdWxkIGJlIGJldHRlci4K