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=-10.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 00BA5C4361B for ; Fri, 4 Dec 2020 19:05:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B47C622CA1 for ; Fri, 4 Dec 2020 19:04:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729780AbgLDTEo (ORCPT ); Fri, 4 Dec 2020 14:04:44 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52032 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726021AbgLDTEo (ORCPT ); Fri, 4 Dec 2020 14:04:44 -0500 Received: from mail-ed1-x529.google.com (mail-ed1-x529.google.com [IPv6:2a00:1450:4864:20::529]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 04A9BC061A4F for ; Fri, 4 Dec 2020 11:04:04 -0800 (PST) Received: by mail-ed1-x529.google.com with SMTP id v22so6924373edt.9 for ; Fri, 04 Dec 2020 11:04:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:from:date:message-id:subject:to:cc; bh=MqRGZy01kstwz9ClfAxBNg8au7mjb5Di2jtSuxAThnw=; b=cKh7YAPyiW5dF2YKcQ6YErWfHBKONF7uMnPY9TYmHN7gPmV7kfqvsO4K0lg++uClO4 /NKlA32KStz5R5xgk/EmX5yO3AeBxOVahoO7Cr/jlnA8KqQqzxvURXxN06PLGzr6WMff onAd2r/QLhG3fZ+UTnXB7iwVosDOUPxQfGz4C8bJhE2yN1OhePi+9XpIiqRjOES4G6Us PH6bCU13CsY7mDMvTvYQ/b13hFDg5UwUmsOMVIFCogK/Kz+7mHZ64tLeW9PR81vJ+une J/od/fTCV8y1bBhUuty/kWa4a3dAtkQmR1L+3v7h8E1Ampsvk9MEVlznXOkGJ/x6L0eQ FnYg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:from:date:message-id:subject:to:cc; bh=MqRGZy01kstwz9ClfAxBNg8au7mjb5Di2jtSuxAThnw=; b=t6C2WUfuSnDDs4zQ2SGTVF22pMZP3CTrjlyHa2wnnB9S34QOoblj6hJLMwSUcGsc4m lz6+gsNr8w1kk/1IrN4Nsaq+66+F3noV1LWZBVKdECAQyvphoaY+y67XvSVr8ui22Ea3 6gvDNJ4Ow69eTHs9Xg1+pAT7EAnlUpi+BbWIXGPdB7u+eEb5Et7emufXPrpapgsrB5P5 pOkiNxXC5LPYrgwDBZX/93VYgjW97kw6xAdkpCq19fTdCA6sU7QHG5JkCATtgs77xP7p tXS82Es21cUo5QNsVKd05JE5oKxKTRHnF7xgAwh7beo9wdC219cJe84/krW1gi7I2fQT nkgw== X-Gm-Message-State: AOAM533lssEkLk/jRS4aFlDCdfPY+4GBgjPrwBVKGKD0/ViMIZVAbB3O 7xcJQPt8pKxJSHrotDWnzetW3SdJJH7hSW76uSAuzC9eCJOYRT64 X-Google-Smtp-Source: ABdhPJwhhMhsQr+VWTK66ALmYBtYgDGk3593gFW7FRQCJRH8kC4J57TPK3zbqIHhm1yF098qCGo9CPVlPYN9XjZIZrQ= X-Received: by 2002:aa7:da8f:: with SMTP id q15mr8904092eds.239.1607108642178; Fri, 04 Dec 2020 11:04:02 -0800 (PST) MIME-Version: 1.0 From: Naresh Kamboju Date: Sat, 5 Dec 2020 00:33:51 +0530 Message-ID: Subject: BUG: KCSAN: data-race in tick_nohz_next_event / tick_nohz_stop_tick To: open list , kasan-dev , rcu@vger.kernel.org, lkft-triage@lists.linaro.org Cc: Marco Elver , Peter Zijlstra , "Paul E. McKenney" , Ingo Molnar , Thomas Gleixner , fweisbec@gmail.com, Arnd Bergmann Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org LKFT started testing KCSAN enabled kernel from the linux next tree. Here we have found BUG: KCSAN: data-race in tick_nohz_next_event / tick_nohz_stop_tick 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. [ 47.811425] BUG: KCSAN: data-race in tick_nohz_next_event / tick_nohz_stop_tick [ 47.818738] [ 47.820239] write to 0xffffffffa4cbe920 of 4 bytes by task 0 on cpu 2: [ 47.826766] tick_nohz_stop_tick+0x8b/0x310 [ 47.830951] tick_nohz_idle_stop_tick+0xcb/0x170 [ 47.835571] do_idle+0x193/0x250 [ 47.838804] cpu_startup_entry+0x25/0x30 [ 47.842728] start_secondary+0xa0/0xb0 [ 47.846482] secondary_startup_64_no_verify+0xc2/0xcb [ 47.851531] [ 47.853034] read to 0xffffffffa4cbe920 of 4 bytes by task 0 on cpu 3: [ 47.859473] tick_nohz_next_event+0x165/0x1e0 [ 47.863831] tick_nohz_get_sleep_length+0x94/0xd0 [ 47.868539] menu_select+0x250/0xac0 [ 47.872116] cpuidle_select+0x47/0x50 [ 47.875781] do_idle+0x17c/0x250 [ 47.879015] cpu_startup_entry+0x25/0x30 [ 47.882942] start_secondary+0xa0/0xb0 [ 47.886694] secondary_startup_64_no_verify+0xc2/0xcb [ 47.891743] [ 47.893234] Reported by Kernel Concurrency Sanitizer on: [ 47.898541] CPU: 3 PID: 0 Comm: swapper/3 Not tainted 5.10.0-rc6-next-20201201 #2 [ 47.906017] Hardware name: Supermicro SYS-5019S-ML/X11SSH-F, BIOS 2.2 05/23/2018 metadata: git_repo: https://gitlab.com/aroxell/lkft-linux-next target_arch: x86 toolchain: clang-11 git_describe: next-20201201 download_url: https://builds.tuxbuild.com/1l8eiWgGMi6W4aDobjAAlOleFVl/ Full test log link, https://lkft.validation.linaro.org/scheduler/job/2002643#L2019 -- Linaro LKFT https://lkft.linaro.org