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=-5.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 DB040C0018C for ; Mon, 7 Dec 2020 11:52:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 959792333F for ; Mon, 7 Dec 2020 11:52:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726869AbgLGLwQ (ORCPT ); Mon, 7 Dec 2020 06:52:16 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43720 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726712AbgLGLwP (ORCPT ); Mon, 7 Dec 2020 06:52:15 -0500 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 44DC4C0613D2; Mon, 7 Dec 2020 03:51:35 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=Tg95pwKVfQPUA8PWvLFZbteHSebozu5OxDajnVjWT7Q=; b=u1zSahYWjFBIP5IjABN49An1Lw Ih6LRN0GYM8r8c4EgAJe5wiBDgjqi8sbVf179ZZCyjOKoSmfmbx5AexCoBLGSC0acL/ZrdoG+KhWg 5NC11Ug4yLcTlqyAcAGKZOmNEEphtUMSxLpIuPUdtAHLnqlZhe0/s2wE4AOD8oSERNWikv1IVrSKp ArrkBcC9fY0cDmnNtx3f15fswRylgYxDVeR6tVybb+buu+yvDdW6OTI9JqGpya83wgA0mHakERdSJ T/EhHLeVsQn7w5Nk6IvrPt0sZaDxJuYxcyOXLwHXhzH+yrwlnhxItdXWed9Odgv3fcFAL2KN+facw p4btqyRw==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kmF2z-0000Ii-Rc; Mon, 07 Dec 2020 11:51:18 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 0F7AB303DA0; Mon, 7 Dec 2020 12:51:16 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id E9D9E2081295B; Mon, 7 Dec 2020 12:51:15 +0100 (CET) Date: Mon, 7 Dec 2020 12:51:15 +0100 From: Peter Zijlstra To: Naresh Kamboju Cc: open list , linux-usb@vger.kernel.org, lkft-triage@lists.linaro.org, rcu@vger.kernel.org, kasan-dev , Greg Kroah-Hartman , "Paul E. McKenney" , Marco Elver , Ingo Molnar , Will Deacon , Lee Jones , Thierry Reding , mathias.nyman@linux.intel.com, Qian Cai Subject: Re: BUG: KCSAN: data-race in mutex_spin_on_owner+0xef/0x1b0 Message-ID: <20201207115115.GL3040@hirez.programming.kicks-ass.net> References: 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-kernel@vger.kernel.org On Fri, Dec 04, 2020 at 11:51:39PM +0530, Naresh Kamboju wrote: > LKFT started testing KCSAN enabled kernel from the linux next tree. > Here we have found BUG: KCSAN: data-race in mutex_spin_on_owner > and several more KCSAN BUGs. > > This report is from an x86_64 machine clang-11 linux next 20201201. > Since we are running for the first time we do not call this regression. > > [ 4.745161] usbcore: registered new interface driver cdc_ether > [ 4.751281] ================================================================== > [ 4.756653] usbcore: registered new interface driver net1080 > [ 4.752139] BUG: KCSAN: data-race in mutex_spin_on_owner+0xef/0x1b0 At the very least run your splat through ./scripts/decode_stacktrace.sh It's impossible to know what the thing is complaining about. I suspect this is one of those known KCSAN 'bugs' where it can't tell a load+cmp0 is perfectly fine.