Return-path: Received: from mx1.redhat.com ([209.132.183.28]:43817 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932781AbcCQOoU (ORCPT ); Thu, 17 Mar 2016 10:44:20 -0400 From: Jes Sorensen To: Julian Calaby Cc: Jandy Gou , Larry Finger , Greg KH , linux-wireless , "devel\@driverdev.osuosl.org" , "linux-kernel\@vger.kernel.org" Subject: Re: [PATCH] staging: r8723au: This patch tries to fix some byte order issues that is found by sparse check. References: <1458201839-7007-1-git-send-email-qingsong.gou@ck-telecom.com> Date: Thu, 17 Mar 2016 10:44:19 -0400 In-Reply-To: (Julian Calaby's message of "Thu, 17 Mar 2016 20:18:59 +1100") Message-ID: (sfid-20160317_154445_644550_82ABDBA5) MIME-Version: 1.0 Content-Type: text/plain Sender: linux-wireless-owner@vger.kernel.org List-ID: Julian Calaby writes: > Hi Jandy, > > On Thu, Mar 17, 2016 at 7:03 PM, Jandy Gou wrote: >> make C=1 M=drivers/staging/rtl8723au/ >> >> drivers/staging/rtl8723au/hal/rtl8723a_cmd.c:96:38: warning: cast to >> restricted __le16 >> drivers/staging/rtl8723au/hal/rtl8723a_cmd.c:100:27: warning: cast to >> restricted __le32 >> >> Signed-off-by: Jandy Gou > > I'm not sure your change is correct. Perhaps you should add temporary > variables for h2c_cmd_ex and h2c_cmd while they're cpu-endian? > > Jes, > > I'm pretty sure this isn't the first time this has come up. Do you > have any ideas for a solution? Or should we ignore this as this driver > will eventually be going away? Temp variables as you suggest would be a clean way to accomplish this. Technically this might work, but esthetically this is so gross I wish I had never seen it. There is a reason why we have the byteorder specific types, and le{16,32}_to_cpus() violates that. I am surprised we still have these macros around, tbh I didn't even know they existed. A quick search for le16_to_cpus() shows that it's really very old drivers and some more recent Intel Ethernet drivers that use them - maybe this would be a good time to get rid of them completely. Cheers, Jes