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=-8.7 required=3.0 tests=BAYES_00, 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 EAB86C4361B for ; Mon, 14 Dec 2020 06:09:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8CFD7229F0 for ; Mon, 14 Dec 2020 06:09:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391916AbgLNGJy (ORCPT ); Mon, 14 Dec 2020 01:09:54 -0500 Received: from mo-csw1516.securemx.jp ([210.130.202.155]:52948 "EHLO mo-csw.securemx.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727666AbgLNGJy (ORCPT ); Mon, 14 Dec 2020 01:09:54 -0500 Received: by mo-csw.securemx.jp (mx-mo-csw1516) id 0BE67wbX017540; Mon, 14 Dec 2020 15:07:58 +0900 X-Iguazu-Qid: 34tKVBJTs7nslYEG8C X-Iguazu-QSIG: v=2; s=0; t=1607926077; q=34tKVBJTs7nslYEG8C; m=LRAxgXNrX/mzO1a6jFP2Mf6RSEFZqpRUWrl8/IEP8TU= Received: from imx12.toshiba.co.jp (imx12.toshiba.co.jp [61.202.160.132]) by relay.securemx.jp (mx-mr1513) id 0BE67vuv032165; Mon, 14 Dec 2020 15:07:57 +0900 Received: from enc02.toshiba.co.jp ([61.202.160.51]) by imx12.toshiba.co.jp with ESMTP id 0BE67vbv017136; Mon, 14 Dec 2020 15:07:57 +0900 (JST) Received: from hop101.toshiba.co.jp ([133.199.85.107]) by enc02.toshiba.co.jp with ESMTP id 0BE67uXi012587; Mon, 14 Dec 2020 15:07:56 +0900 From: Punit Agrawal To: Colin Ian King Cc: Subject: Re: RT kernel testing with stress-ng and scheduling while in atomic bugs. References: Date: Mon, 14 Dec 2020 15:07:54 +0900 In-Reply-To: (Colin Ian King's message of "Mon, 7 Dec 2020 12:43:47 +0000") X-TSB-HOP: ON Message-ID: <878sa03op1.fsf@kokedama.swc.toshiba.co.jp> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-rt-users@vger.kernel.org Hi Colin, Colin Ian King writes: > Hi, > > I've recently been exercising the 5.10-rc6 kernel with the latest RT > patches from linux-rt-devel (v5.10-rc6-rt13) using stress-ng V0.12.00 > [1][2] to see rugged the RT kernel is and I'm getting quite a few > "scheduling while atomic:" bugs in various stress-tests. > > While I realize this is a rc6 kernel, I was surprised to be able to trip > these issues so easily [3] > > Questions: > > 1. Are these issues expected? > 2. Is there an official way to report my bug findings? > 3. I am keen to debug and fix these issues, have RT folk got some advice > on how to start debugging these kind of issues? > > On an 8 CPU SMP test box stress-ng is hitting these issues on the > following stress tests: > > daemon enosys exec fork fstat madvise prctl pthread session sigpipe vfork > > ..it seems fork/clone + scheduling is the common feature in the stress > tests that is triggering this issue. > > How to reproduce: > > git clone https://github.com/ColinIanKing/stress-ng.git > cd stress-ng > make clean > make fast-test-all I tried to reproduce the failures bug am not getting any errors following the above steps. ~/src/stress-ng$ make fast-test-all ... stress-ng: 14:20:53.88 debug: [261118] metrics-check: all stressor metrics validated and sane zombie PASSED 240 PASSED 0 FAILED 7 SKIPPED, bind-mount binderfs cpu-online mlockmany oom-pipe sysinval watchdog Not sure if the problems you saw were fixed in the interim but I am using 5.10.0-rc6-rt14 on a quad core Apollolake system. Are there any configs that need enabling? I used defconfig + Intel LPSS for platform support + PREEMPT_RT. Thanks, Punit [...]