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=-7.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 0F9DCC432C3 for ; Thu, 14 Nov 2019 22:16:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D4C72206E6 for ; Thu, 14 Nov 2019 22:16:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573769763; bh=LDvzI/ip5iI4UIoBSOL32SYOqpndu86kZkkikom9zAQ=; h=Date:From:To:Cc:Subject:Reply-To:References:In-Reply-To:List-ID: From; b=IpQ5WjCUBASrr8VH7OE/R0w+3lVd8VPcVN/6vl49EgSIaun3DkUCeqB8O1IuZ4v4N kvGTQRadi0KAILwFp1z6w6dMZzscrYUHC0UZgwym3pg7+OhMvyMTc8tXBOL247Vu3m OMmJkcQqSKSBYJjIv46KWva+FpOL6jIlBoFml1Pg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726881AbfKNWQD (ORCPT ); Thu, 14 Nov 2019 17:16:03 -0500 Received: from mail.kernel.org ([198.145.29.99]:52494 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726613AbfKNWQD (ORCPT ); Thu, 14 Nov 2019 17:16:03 -0500 Received: from paulmck-ThinkPad-P72.home (unknown [199.201.64.141]) (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 B271420709; Thu, 14 Nov 2019 22:16:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573769762; bh=LDvzI/ip5iI4UIoBSOL32SYOqpndu86kZkkikom9zAQ=; h=Date:From:To:Cc:Subject:Reply-To:References:In-Reply-To:From; b=evw1x+V8DbAMm1Q56y0Dl8nBXH4RuSVwxeqMsDfteUCdnCAMqUInQ8/2NhtcogIZ+ xon7nkORRkUbI4++x7nww4haJsBSqgHMLJ4ZzVmMjc54kDTtedT8QMdT/6hOh7Oex2 5vtVN19MYBPsP0sLIPE24mpdYfNsH0MiSEQ8OF60= Received: by paulmck-ThinkPad-P72.home (Postfix, from userid 1000) id 87E8835227FC; Thu, 14 Nov 2019 14:15:59 -0800 (PST) Date: Thu, 14 Nov 2019 14:15:59 -0800 From: "Paul E. McKenney" To: Marco Elver Cc: akiyks@gmail.com, stern@rowland.harvard.edu, glider@google.com, parri.andrea@gmail.com, andreyknvl@google.com, luto@kernel.org, ard.biesheuvel@linaro.org, arnd@arndb.de, boqun.feng@gmail.com, bp@alien8.de, dja@axtens.net, dlustig@nvidia.com, dave.hansen@linux.intel.com, dhowells@redhat.com, dvyukov@google.com, hpa@zytor.com, mingo@redhat.com, j.alglave@ucl.ac.uk, joel@joelfernandes.org, corbet@lwn.net, jpoimboe@redhat.com, luc.maranget@inria.fr, mark.rutland@arm.com, npiggin@gmail.com, peterz@infradead.org, tglx@linutronix.de, will@kernel.org, edumazet@google.com, kasan-dev@googlegroups.com, linux-arch@vger.kernel.org, linux-doc@vger.kernel.org, linux-efi@vger.kernel.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, x86@kernel.org Subject: Re: [PATCH v4 00/10] Add Kernel Concurrency Sanitizer (KCSAN) Message-ID: <20191114221559.GS2865@paulmck-ThinkPad-P72> Reply-To: paulmck@kernel.org References: <20191114180303.66955-1-elver@google.com> <20191114195046.GP2865@paulmck-ThinkPad-P72> <20191114213303.GA237245@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191114213303.GA237245@google.com> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-efi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org On Thu, Nov 14, 2019 at 10:33:03PM +0100, Marco Elver wrote: > On Thu, 14 Nov 2019, Paul E. McKenney wrote: > > > On Thu, Nov 14, 2019 at 07:02:53PM +0100, Marco Elver wrote: > > > This is the patch-series for the Kernel Concurrency Sanitizer (KCSAN). > > > KCSAN is a sampling watchpoint-based *data race detector*. More details > > > are included in **Documentation/dev-tools/kcsan.rst**. This patch-series > > > only enables KCSAN for x86, but we expect adding support for other > > > architectures is relatively straightforward (we are aware of > > > experimental ARM64 and POWER support). > > > > > > To gather early feedback, we announced KCSAN back in September, and have > > > integrated the feedback where possible: > > > http://lkml.kernel.org/r/CANpmjNPJ_bHjfLZCAPV23AXFfiPiyXXqqu72n6TgWzb2Gnu1eA@mail.gmail.com > > > > > > The current list of known upstream fixes for data races found by KCSAN > > > can be found here: > > > https://github.com/google/ktsan/wiki/KCSAN#upstream-fixes-of-data-races-found-by-kcsan > > > > > > We want to point out and acknowledge the work surrounding the LKMM, > > > including several articles that motivate why data races are dangerous > > > [1, 2], justifying a data race detector such as KCSAN. > > > > > > [1] https://lwn.net/Articles/793253/ > > > [2] https://lwn.net/Articles/799218/ > > > > I queued this and ran a quick rcutorture on it, which completed > > successfully with quite a few reports. > > Great. Many thanks for queuing this in -rcu. And regarding merge window > you mentioned, we're fine with your assumption to targeting the next > (v5.6) merge window. > > I've just had a look at linux-next to check what a future rebase > requires: > > - There is a change in lib/Kconfig.debug and moving KCSAN to the > "Generic Kernel Debugging Instruments" section seems appropriate. > - bitops-instrumented.h was removed and split into 3 files, and needs > re-inserting the instrumentation into the right places. > > Otherwise there are no issues. Let me know what you recommend. Sounds good! I will be rebasing onto v5.5-rc1 shortly after it comes out. My usual approach is to fix any conflicts during that rebasing operation. Does that make sense, or would you prefer to send me a rebased stack at that point? Either way is fine for me. Thanx, Paul