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 AE417C54EBC for ; Wed, 11 Jan 2023 01:47:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231989AbjAKBrG (ORCPT ); Tue, 10 Jan 2023 20:47:06 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32886 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231151AbjAKBrF (ORCPT ); Tue, 10 Jan 2023 20:47:05 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A9BAA63C9; Tue, 10 Jan 2023 17:47:04 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 45B2E619D6; Wed, 11 Jan 2023 01:47:04 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 16CA4C433D2; Wed, 11 Jan 2023 01:47:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1673401623; bh=9wEvjZ7+McmNbo2jlG6VOYF0uVrSmbCh6cUh5UaKJ5k=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=k2NSqDYrGa1Q8yEa9nrREKICA0DkzvUhcUS3M8ZN8iv2F0WYvfx0w0reVAQj2qzJJ sFickMGMAbggSsGFPFxpW/EX+nSFOHYWBm457on5Ihk1L9nvbVSZlZZT8uNqVgNO5i LJiTPoy8TnHEKTE0hkLAzVEVrL45twRl9sHTsDMmuLHc44+eDN+L6k8AU3WEds+91L dBpySKs9AdIZVLupsoFbhOqGmahXoc5xt+D0tFFSDQP+o9mDnv0QG3/ieGLNJwQLHE GfizsD25hYOY3eD4AJT1U0oS6boDQKM7YAiu53qioZvobaNDnAVt38dBoQZM5lgdzo 8migqnt83OaIw== Date: Tue, 10 Jan 2023 17:47:02 -0800 From: Jakub Kicinski To: syzbot Cc: acme@kernel.org, alexander.shishkin@linux.intel.com, bpf@vger.kernel.org, jolsa@kernel.org, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, mark.rutland@arm.com, mingo@redhat.com, namhyung@kernel.org, netdev@vger.kernel.org, peterz@infradead.org, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] WARNING: locking bug in __perf_event_task_sched_in (2) Message-ID: <20230110174702.72fe74c7@kernel.org> In-Reply-To: <000000000000dde02b05f1ef09a4@google.com> References: <000000000000dde02b05f1ef09a4@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-perf-users@vger.kernel.org On Tue, 10 Jan 2023 12:50:48 -0800 syzbot wrote: > > lock_acquire kernel/locking/lockdep.c:5668 [inline] > lock_acquire+0x1e3/0x630 kernel/locking/lockdep.c:5633 > rcu_lock_acquire include/linux/rcupdate.h:325 [inline] > rcu_read_lock include/linux/rcupdate.h:764 [inline] > perf_event_context_sched_in kernel/events/core.c:3913 [inline] > __perf_event_task_sched_in+0xe2/0x6c0 kernel/events/core.c:3980 > perf_event_task_sched_in include/linux/perf_event.h:1328 [inline] > finish_task_switch.isra.0+0x5e5/0xc80 kernel/sched/core.c:5118 > context_switch kernel/sched/core.c:5247 [inline] > __schedule+0xb92/0x5450 kernel/sched/core.c:6555 > schedule+0xde/0x1b0 kernel/sched/core.c:6631 > schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6690 > __mutex_lock_common kernel/locking/mutex.c:679 [inline] > __mutex_lock+0xa48/0x1360 kernel/locking/mutex.c:747 > devl_lock net/devlink/core.c:54 [inline] > devlink_pernet_pre_exit+0x10a/0x220 net/devlink/core.c:301 > ops_pre_exit_list net/core/net_namespace.c:159 [inline] > cleanup_net+0x455/0xb10 net/core/net_namespace.c:594 > process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 > worker_thread+0x669/0x1090 kernel/workqueue.c:2436 > kthread+0x2e8/0x3a0 kernel/kthread.c:376 > ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 > Yes, I pooped it. We need to keep the mutex around as well as the devlink instance memory, otherwise locked screams. Fix building..