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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 D5742C433E0 for ; Thu, 21 May 2020 13:36:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ABBA62072C for ; Thu, 21 May 2020 13:36:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590068193; bh=k1U9skoq/IsxYcIdWWwltNtKISxIBRqA2/fMuQ1l6/s=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=pjDkFwZTwW9+lyEup8lsKpLnHEhWw9JaSke4K29ca75tHzGG7ezdAfIhhzv9jopW3 QadTGEQCkr0sBhION4tPnqdRgj4fllX4l6PFn3BdgPIw37I2PQJjHLtwd5zI2GkFuj Ig+geNv3kR6nJsZYcxHTPjdBAfxzd/j/kgXDoqAU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728110AbgEUNgc (ORCPT ); Thu, 21 May 2020 09:36:32 -0400 Received: from mail.kernel.org ([198.145.29.99]:39624 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726856AbgEUNgc (ORCPT ); Thu, 21 May 2020 09:36:32 -0400 Received: from willie-the-truck (236.31.169.217.in-addr.arpa [217.169.31.236]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 02B1720721; Thu, 21 May 2020 13:36:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590068192; bh=k1U9skoq/IsxYcIdWWwltNtKISxIBRqA2/fMuQ1l6/s=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=fiiMcKpG6X/JtSWMRjsdR4p6LuRA638LAeg+KATziaRhN/rYR30X+H1cRyg2j6sNR 7Un+7kyMPRvtO7ty1OSPtx03+GEGN+hUfOWrR7Xt8mWojHmBThZGBavKtafysKxzk4 xlvFQK7Fl0BjhVJGb4cXmwQ0GdzDlyuU512y8Dvk= Date: Thu, 21 May 2020 14:36:27 +0100 From: Will Deacon To: Marco Elver Cc: paulmck@kernel.org, dvyukov@google.com, glider@google.com, andreyknvl@google.com, kasan-dev@googlegroups.com, linux-kernel@vger.kernel.org, tglx@linutronix.de, mingo@kernel.org, peterz@infradead.org, clang-built-linux@googlegroups.com, bp@alien8.de Subject: Re: [PATCH -tip v2 00/11] Fix KCSAN for new ONCE (require Clang 11) Message-ID: <20200521133626.GD6608@willie-the-truck> References: <20200521110854.114437-1-elver@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200521110854.114437-1-elver@google.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 21, 2020 at 01:08:43PM +0200, Marco Elver wrote: > This patch series is the conclusion to [1], where we determined that due > to various interactions with no_sanitize attributes and the new > {READ,WRITE}_ONCE(), KCSAN will require Clang 11 or later. Other > sanitizers are largely untouched, and only KCSAN now has a hard > dependency on Clang 11. To test, a recent Clang development version will > suffice [2]. While a little inconvenient for now, it is hoped that in > future we may be able to fix GCC and re-enable GCC support. > > The patch "kcsan: Restrict supported compilers" contains a detailed list > of requirements that led to this decision. > > Most of the patches are related to KCSAN, however, the first patch also > includes an UBSAN related fix and is a dependency for the remaining > ones. The last 2 patches clean up the attributes by moving them to the > right place, and fix KASAN's way of defining __no_kasan_or_inline, > making it consistent with KCSAN. > > The series has been tested by running kcsan-test several times and > completed successfully. I've left a few minor comments, but the only one that probably needs a bit of thought is using data_race() with const non-scalar expressions, since I think that's now prohibited by these changes. We don't have too many data_race() users yet, so probably not a big deal, but worth bearing in mind. Other than that, Acked-by: Will Deacon Thanks! Will