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=-5.8 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 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 D485BC433ED for ; Sun, 4 Apr 2021 20:38:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A184661246 for ; Sun, 4 Apr 2021 20:38:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231592AbhDDUix (ORCPT ); Sun, 4 Apr 2021 16:38:53 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:48094 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231453AbhDDUit (ORCPT ); Sun, 4 Apr 2021 16:38:49 -0400 From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1617568722; h=from:from:reply-to:subject:subject: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=RKJOVw49h8LPa1c5z5Qs/Q0pL2+AWkIVuAy0NwtgdHY=; b=KDQYJd2P4atFmXEh7pGIsauueG9uEzg6bw5pL17rkaASxtR9Q00u17I815CMkvCukIQxIk Ya4xMsuKk9wN9zwk3sPYVGLz/V7qPg8sX3/kaJF98JzrBy+bBu5dw2coIbyNbQEFlB3Mwv PKCaT8EzFSxW/xK+f2HboNfuBDFSyxk6ya5y4DbXRVLV31smQJKt8a0Rf4JpG0/yu7zDxY 5eIYoIXGK81beV+rvgA6z7sgvDhCvKJzYVLhOEadrlCR+udQ+jtF6JmmvT6CjwVv8iiei5 WzC2PJgKl/7NyCAHKPAu0aHKI5U3O0J6wi7x7VcpzCc86xi7+qIK9lGUBw5mCw== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1617568722; h=from:from:reply-to:subject:subject: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=RKJOVw49h8LPa1c5z5Qs/Q0pL2+AWkIVuAy0NwtgdHY=; b=kZFbhVKKO5yVfSuOtEYd9bPBB2QhiOhqwJWEQfCoKWrZBDVhCq3N8kJSqf/UvEl1M95ECD Ebn8DJjofUvRsXCA== To: syzbot Cc: john.stultz@linaro.org, linux-kernel@vger.kernel.org, sboyd@kernel.org, syzkaller-bugs@googlegroups.com, Peter Zijlstra , "Paul E. McKenney" Subject: Re: [syzbot] WARNING: suspicious RCU usage in get_timespec64 In-Reply-To: <0000000000000e025b05bf2a430b@google.com> References: <0000000000000e025b05bf2a430b@google.com> Date: Sun, 04 Apr 2021 22:38:41 +0200 Message-ID: <87mtud4wfi.ffs@nanos.tec.linutronix.de> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Apr 04 2021 at 12:05, syzbot wrote: Cc + ... > Hello, > > syzbot found the following issue on: > > HEAD commit: 5e46d1b7 reiserfs: update reiserfs_xattrs_initialized() co.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=1125f831d00000 > kernel config: https://syzkaller.appspot.com/x/.config?x=78ef1d159159890 > dashboard link: https://syzkaller.appspot.com/bug?extid=88e4f02896967fe1ab0d > > Unfortunately, I don't have any reproducer for this issue yet. > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+88e4f02896967fe1ab0d@syzkaller.appspotmail.com > > ============================= > WARNING: suspicious RCU usage > 5.12.0-rc5-syzkaller #0 Not tainted > ----------------------------- > kernel/sched/core.c:8294 Illegal context switch in RCU-sched read-side critical section! > > other info that might help us debug this: > > > rcu_scheduler_active = 2, debug_locks = 0 > 3 locks held by syz-executor.4/8418: > #0: > ffff8880751d2b28 > ( > &p->pi_lock > ){-.-.}-{2:2} > , at: try_to_wake_up+0x98/0x14a0 kernel/sched/core.c:3345 > #1: > ffff8880b9d35258 > ( > &rq->lock > ){-.-.}-{2:2} > , at: rq_lock kernel/sched/sched.h:1321 [inline] > , at: ttwu_queue kernel/sched/core.c:3184 [inline] > , at: try_to_wake_up+0x5e6/0x14a0 kernel/sched/core.c:3464 > #2: ffff8880b9d1f948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_change+0x142/0x220 kernel/sched/psi.c:807 > > stack backtrace: > CPU: 0 PID: 8418 Comm: syz-executor.4 Not tainted 5.12.0-rc5-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > Call Trace: > __dump_stack lib/dump_stack.c:79 [inline] > dump_stack+0x141/0x1d7 lib/dump_stack.c:120 > ___might_sleep+0x266/0x2c0 kernel/sched/core.c:8294 > __might_fault+0x6e/0x180 mm/memory.c:5018 > _copy_from_user+0x27/0x180 lib/usercopy.c:13 > copy_from_user include/linux/uaccess.h:192 [inline] > get_timespec64+0x75/0x220 kernel/time/time.c:787 > __do_sys_clock_nanosleep kernel/time/posix-timers.c:1257 [inline] > __se_sys_clock_nanosleep kernel/time/posix-timers.c:1245 [inline] > __x64_sys_clock_nanosleep+0x1bb/0x430 kernel/time/posix-timers.c:1245 > do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 > entry_SYSCALL_64_after_hwframe+0x44/0xae > RIP: 0033:0x48a621 > Code: 24 0c 89 3c 24 48 89 4c 24 18 e8 aa e7 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 8b 74 24 0c 8b 3c 24 b8 e6 00 00 00 0f 05 <44> 89 c7 48 89 04 24 e8 e3 e7 ff ff 48 8b 04 24 eb 97 66 2e 0f 1f > RSP: 002b:00007fffe59fbd50 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 > RAX: ffffffffffffffda RBX: 0000000000000294 RCX: 000000000048a621 > RDX: 00007fffe59fbd90 RSI: 0000000000000000 RDI: 0000000000000000 > RBP: 00007fffe59fbe2c R08: 0000000000000000 R09: 00007fffe5b8a090 > R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000032 > R13: 000000000005717a R14: 0000000000000003 R15: 00007fffe59fbe90 > > > --- > This report is generated by a bot. It may contain errors. > See https://goo.gl/tpsmEJ for more information about syzbot. > syzbot engineers can be reached at syzkaller@googlegroups.com. > > syzbot will keep track of this issue. See: > https://goo.gl/tpsmEJ#status for how to communicate with syzbot.