From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from verein.lst.de ([213.95.11.211]:37217 "EHLO newverein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965793AbdEYNA3 (ORCPT ); Thu, 25 May 2017 09:00:29 -0400 Date: Thu, 25 May 2017 15:00:27 +0200 From: Christoph Hellwig Subject: Re: [PATCH 10/23] afs: switch to use uuid_t and uuid_gen Message-ID: <20170525130027.GA30194@lst.de> References: <20170518062705.25902-1-hch@lst.de> <20170518062705.25902-11-hch@lst.de> <1495478957.6967.69.camel@linux.intel.com> <20170523084956.GB20121@lst.de> <1495545099.6967.81.camel@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1495545099.6967.81.camel@linux.intel.com> Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: Andy Shevchenko Cc: Christoph Hellwig , Amir Goldstein , linux-fsdevel@vger.kernel.org, Shaohua Li , Dan Williams , David Howells , Steven Whitehouse , Mimi Zohar , linux-xfs@vger.kernel.org, linux-raid@vger.kernel.org, linux-nvdimm@lists.01.org, linux-kernel@vger.kernel.org On Tue, May 23, 2017 at 04:11:39PM +0300, Andy Shevchenko wrote: > Since we introduced a union it's possible that we might access the > member which wasn't last modified one. So, my comment is to give an > attention on such possibility and avoid if there is an aliasing > happened. We do for AFS (and XFS for fs fsid). My preference would be to not have the v1 struct defintion but instead provide a few helpers in uuid.h that use get_unaligned_be* if needed: uuid_v1_time_low() uuid_v1_time_mid() uuid_v1_time_time_hi_and_version().. >>From his previously reply it seems like Dave doesn't like that idea too much, in which case I suspect moving struct uuid_v1 back into afs and living with cast in it is the way to go.