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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 233C1CA5520 for ; Wed, 13 Sep 2023 09:29:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238527AbjIMJ32 (ORCPT ); Wed, 13 Sep 2023 05:29:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38460 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237229AbjIMJ31 (ORCPT ); Wed, 13 Sep 2023 05:29:27 -0400 Received: from smtp-out1.suse.de (smtp-out1.suse.de [195.135.220.28]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6DAF4EC; Wed, 13 Sep 2023 02:29:23 -0700 (PDT) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id 15779218E8; Wed, 13 Sep 2023 09:29:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1694597362; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=3zkN0jprRlNgAWBNnwR9+n4RWOVj4MMw+4ONI9DbmTg=; b=sy/7mX2iw7iKv8P9spaqJzKhuvhMTMG7zNwc5tSfPCX0r8mq5sC5YkIUe+u9AxXK4XSUqs cR6JPoEcWTiAwdkObk2E+nbLNrdNFostv0/2Cn4Az6qCOMdUEl8g1Et3jILR0xBH8KbkpP Ci0yCSTsutSN0D9fjp49FPxHDkzu0ck= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1694597362; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=3zkN0jprRlNgAWBNnwR9+n4RWOVj4MMw+4ONI9DbmTg=; b=CNYrhCga/C9N/KHhBo2n4aWMUeeYw4VKE6KPB/ijC8ftosBsahMcvFujh2F7XJFh61XT6b jBGdb8BTnnSy0jAw== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 05FCC13582; Wed, 13 Sep 2023 09:29:22 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id j0s1APKAAWUvRAAAMHmgww (envelope-from ); Wed, 13 Sep 2023 09:29:22 +0000 Date: Wed, 13 Sep 2023 11:30:08 +0200 From: Cyril Hrubis To: Naresh Kamboju Cc: open list , LTP List , Linux PM , Alex =?iso-8859-1?Q?Benn=E9e?= , Anders Roxell , Arnd Bergmann , Vincent Guittot , Wei Gao , Peter Zijlstra , Martin Doucha Subject: Re: Qemu-arm64: LTP: cfs_bandwidth01: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000038 Message-ID: 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-pm@vger.kernel.org Hi! > Following kernel crash noticed on Linux stable-rc 6.5.3-rc1 on qemu-arm64 while > running LTP sched tests cases. > > This is not always reproducible. What the test does is to create three levels of cgroups, sets CPU quotas for them, runs bussy loop proceses in the groups and changes the quotas during the time the bussy processes runs. And the test is regression test for quite a few commits: commit 39f23ce07b9355d05a64ae303ce20d1c4b92b957 Author: Vincent Guittot Date: Wed May 13 15:55:28 2020 +0200 sched/fair: Fix unthrottle_cfs_rq() for leaf_cfs_rq list commit b34cb07dde7c2346dec73d053ce926aeaa087303 Author: Phil Auld Date: Tue May 12 09:52:22 2020 -0400 sched/fair: Fix enqueue_task_fair() warning some more commit fe61468b2cbc2b7ce5f8d3bf32ae5001d4c434e9 Author: Vincent Guittot Date: Fri Mar 6 14:52:57 2020 +0100 sched/fair: Fix enqueue_task_fair warning commit 5ab297bab984310267734dfbcc8104566658ebef Author: Vincent Guittot Date: Fri Mar 6 09:42:08 2020 +0100 sched/fair: Fix reordering of enqueue/dequeue_task_fair() commit 6d4d22468dae3d8757af9f8b81b848a76ef4409d Author: Vincent Guittot Date: Mon Feb 24 09:52:14 2020 +0000 sched/fair: Reorder enqueue/dequeue_task_fair path commit fdaba61ef8a268d4136d0a113d153f7a89eb9984 Author: Rik van Riel Date: Mon Jun 21 19:43:30 2021 +0200 sched/fair: Ensure that the CFS parent is added after unthrottling Unless this is a random corruption we should look closer at scheduller changes. -- Cyril Hrubis chrubis@suse.cz