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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,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 1D99DC433B4 for ; Wed, 31 Mar 2021 21:58:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DBA7661078 for ; Wed, 31 Mar 2021 21:58:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230239AbhCaV6Q (ORCPT ); Wed, 31 Mar 2021 17:58:16 -0400 Received: from mail.kernel.org ([198.145.29.99]:42388 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229615AbhCaV6I (ORCPT ); Wed, 31 Mar 2021 17:58:08 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 6438061002; Wed, 31 Mar 2021 21:58:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1617227887; bh=tpoYiSlNk4uwdNJnLdLuFZS9y1Ke2MOr3SuY8iUfrG0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=V8xr6TMOly7cQ3WLUHc4Pai3QxsiNd8PjsPyKEei7jDZQMlnWXa8jO7v+sbq0Oqh/ jOcIWW+2Qgx1VRBcs9VTVrHfvlFPTeSTipLSRLzuPCvfssKyPPGTXe6GS+n7hjLi0P Ceq3PDS5eJtNTHqp3cHrT42/+hJy0gSO9czD4iA/EJfoPAeInPUp+ILK+2OrjDPFeT p+v92MatlkQL62wnwv9/3SSP92FMMEkzDWu/hx7eeidGmWxM6K0pOZ0cpo+Onu1wpZ A02nIpALgnrQCRKMUUsHV7rGtuZxL1ZuBf3VzgclSzy4Du8vB61KrwSLXkkJaM+Uoi iqsGGn8V2v6PQ== Date: Wed, 31 Mar 2021 14:58:02 -0700 From: Nathan Chancellor To: Jian Cai Cc: Guenter Roeck , Christopher Di Bella , Manoj Gupta , Luis Lozano , clang-built-linux , Jens Axboe , Nick Desaulniers , linux-block@vger.kernel.org, Linux Kernel Mailing List Subject: Re: [PATCH] blk-mq: fix alignment mismatch. Message-ID: <20210331215802.r4rp6wynjqutdoup@archlinux-ax161> References: <20210330230249.709221-1-jiancai@google.com> <20210330232946.m5p7426macyjduzm@archlinux-ax161> <114a5697-9b5c-daf1-f0fc-dc190d4db74d@roeck-us.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Hi Jian, On Wed, Mar 31, 2021 at 02:27:03PM -0700, Jian Cai wrote: > Hi Nathan, > > I just realized you already proposed solutions for skipping the check > in https://lore.kernel.org/linux-block/20210310225240.4epj2mdmzt4vurr3@archlinux-ax161/#t. > Do you have any plans to send them for review? > > Thanks, > Jian I was hoping to gather some feedback on which option would be preferred by Jens and the other ClangBuiltLinux folks before I sent them along. I can send the first just to see what kind of feedback I can gather. Cheers, Nathan > On Tue, Mar 30, 2021 at 6:31 PM Jian Cai wrote: > > > > Thanks for all the information. I'll check for similar instances and > > send an updated version. > > > > > > On Tue, Mar 30, 2021 at 5:26 PM Guenter Roeck wrote: > > > > > > On 3/30/21 4:29 PM, Nathan Chancellor wrote: > > > > Hi Jian, > > > > > > > > On Tue, Mar 30, 2021 at 04:02:49PM -0700, Jian Cai wrote: > > > >> This fixes the mismatch of alignments between csd and its use as an > > > >> argument to smp_call_function_single_async, which causes build failure > > > >> when -Walign-mismatch in Clang is used. > > > >> > > > >> Link: > > > >> http://crrev.com/c/1193732 > > > >> > > > >> Suggested-by: Guenter Roeck > > > >> Signed-off-by: Jian Cai > > > > > > > > Thanks for the patch. This is effectively a revert of commit > > > > 4ccafe032005 ("block: unalign call_single_data in struct request"), > > > > which I had brought up in this thread: > > > > > > > > https://lore.kernel.org/r/20210310182307.zzcbi5w5jrmveld4@archlinux-ax161/ > > > > > > > > This is obviously a correct fix, I am not just sure what the impact to > > > > 'struct request' will be. > > > > > > > > > > As commit 4ccafe032005 states, it increases the request structure size. > > > Given the exchange referenced above, I think we'll need to disable > > > the warning in the block code. > > > > > > Thanks, > > > Guenter > > > > > > > Cheers, > > > > Nathan > > > > > > > >> --- > > > >> include/linux/blkdev.h | 2 +- > > > >> 1 file changed, 1 insertion(+), 1 deletion(-) > > > >> > > > >> diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h > > > >> index bc6bc8383b43..3b92330d95ad 100644 > > > >> --- a/include/linux/blkdev.h > > > >> +++ b/include/linux/blkdev.h > > > >> @@ -231,7 +231,7 @@ struct request { > > > >> unsigned long deadline; > > > >> > > > >> union { > > > >> - struct __call_single_data csd; > > > >> + call_single_data_t csd; > > > >> u64 fifo_time; > > > >> }; > > > >> > > > >> -- > > > >> 2.31.0.291.g576ba9dcdaf-goog > > > >> > > >