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,FROM_LOCAL_HEX, 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 91F2AC4727C for ; Thu, 1 Oct 2020 10:35:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5EB442085B for ; Thu, 1 Oct 2020 10:35:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731952AbgJAKfW (ORCPT ); Thu, 1 Oct 2020 06:35:22 -0400 Received: from mail-io1-f77.google.com ([209.85.166.77]:36157 "EHLO mail-io1-f77.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731884AbgJAKfU (ORCPT ); Thu, 1 Oct 2020 06:35:20 -0400 Received: by mail-io1-f77.google.com with SMTP id h8so3241642ioa.3 for ; Thu, 01 Oct 2020 03:35:20 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:date:message-id:subject:from:to; bh=Ltkj0N6myqpJ4BgPE+Vow+4qL+lksAMFkq6rWHx57yI=; b=rpQRGVzyoNiXZ4L9h4LDizsqXGOB8RTcgQb1WrfNTl1r9LO+K5clSlp8xvxPojtjIX 0OAL1KY+yWr0xTUaEOJ7wVRPZYR6e5VztKoeBFvSbDQJ36C5Ejl1It+arDqx3KVSsMTN 5Wq5el9attQTPsA2pgzXHwXug/4DDpAcsp8Y8zkAEQkB5JqEwcvJtVbSK3kZ45oHg+Kr 5+E4Q433UlpFWIilIUraJJ7P5eFgflLcIQxFczuTixMh/BkB3Om4ve6R/0+H5CgzF+qj o9EeYFokCQRDrIDkbx08DrwiyH6ZXcZU9jesDNg2f6dfaTXbZ18Bfgs7i0Krsl9K7uHQ IUWA== X-Gm-Message-State: AOAM530S09WgsKvBZzBfeGAlsIBg50DmiTAJOAQDDzS+5XwINILs2sMv vbHhkqugg6YxHmL3Jxhs4TyIRXp2SF8aDSUzg3GkZh+f3icP X-Google-Smtp-Source: ABdhPJzoQI+3mQ3SACSSbA0Yqw9+g8XDhnBtFtYwH3hh5bO2TSFL4+qMX+6klfgieN1BWaoT0MUNkxWURJ3qlTR4M/14CrnBjxAT MIME-Version: 1.0 X-Received: by 2002:a92:1503:: with SMTP id v3mr1859679ilk.56.1601548519812; Thu, 01 Oct 2020 03:35:19 -0700 (PDT) Date: Thu, 01 Oct 2020 03:35:19 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <0000000000009d327505b0999237@google.com> Subject: INFO: rcu detected stall in batadv_nc_worker (3) From: syzbot To: linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, tglx@linutronix.de Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, syzbot found the following issue on: HEAD commit: fffe3ae0 Merge tag 'for-linus-hmm' of git://git.kernel.org.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=17e03342900000 kernel config: https://syzkaller.appspot.com/x/.config?x=226c7a97d80bec54 dashboard link: https://syzkaller.appspot.com/bug?extid=69904c3b4a09e8fa2e1b compiler: clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81) 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+69904c3b4a09e8fa2e1b@syzkaller.appspotmail.com rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=22e/1/0x4000000000000000 softirq=85361/85365 fqs=8 (detected by 1, t=10502 jiffies, g=114061, q=1511) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 194 Comm: kworker/u4:4 Not tainted 5.8.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:arch_local_save_flags arch/x86/include/asm/paravirt.h:765 [inline] RIP: 0010:arch_local_irq_save arch/x86/include/asm/paravirt.h:787 [inline] RIP: 0010:__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline] RIP: 0010:_raw_spin_lock_irqsave+0x3c/0xc0 kernel/locking/spinlock.c:159 Code: 03 49 bf 00 00 00 00 00 fc ff df 42 80 3c 38 00 74 0c 48 c7 c7 b0 d5 4b 89 e8 a0 97 92 f9 48 83 3d 38 61 2a 01 00 74 79 9c 58 <0f> 1f 44 00 00 49 89 c6 48 c7 c0 c0 d5 4b 89 48 c1 e8 03 42 80 3c RSP: 0018:ffffc90000007d40 EFLAGS: 00000082 RAX: 0000000000000082 RBX: ffffffff8ba182b8 RCX: 000000000000d6e0 RDX: 0000000080010001 RSI: ffffffff894eec80 RDI: ffffffff8ba182b8 RBP: ffffffff894eec80 R08: ffffffff816542f4 R09: fffff52000000fb0 R10: fffff52000000fb0 R11: 0000000000000000 R12: dffffc0000000000 R13: 1ffff11015d04ed2 R14: dffffc0000000000 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000004ddaf0 CR3: 0000000090ca1000 CR4: 00000000001506f0 DR0: 0000000020000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: debug_object_activate+0x62/0x5f0 lib/debugobjects.c:636 debug_hrtimer_activate kernel/time/hrtimer.c:416 [inline] debug_activate kernel/time/hrtimer.c:476 [inline] enqueue_hrtimer kernel/time/hrtimer.c:965 [inline] __run_hrtimer kernel/time/hrtimer.c:1537 [inline] __hrtimer_run_queues+0x510/0x930 kernel/time/hrtimer.c:1584 hrtimer_interrupt+0x373/0xd60 kernel/time/hrtimer.c:1646 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline] __sysvec_apic_timer_interrupt+0xf0/0x260 arch/x86/kernel/apic/apic.c:1097 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline] sysvec_apic_timer_interrupt+0x94/0xf0 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:770 [inline] RIP: 0010:lock_release+0x3c4/0x750 kernel/locking/lockdep.c:5026 Code: 48 c1 e8 03 42 80 3c 28 00 74 0c 48 c7 c7 b8 d5 4b 89 e8 3f 0b 5a 00 48 83 3d df d4 f1 07 00 0f 84 5c 03 00 00 4c 89 e7 57 9d <0f> 1f 44 00 00 65 48 8b 04 25 28 00 00 00 48 3b 44 24 50 0f 85 40 RSP: 0018:ffffc90001037bf8 EFLAGS: 00000282 RAX: 1ffffffff1297ab7 RBX: 1ffff110151d2949 RCX: ffff8880a8e94180 RDX: ffff8880a8e94a48 RSI: ffffffff894ea290 RDI: 0000000000000282 RBP: 9644b5a36c253f0c R08: dffffc0000000000 R09: fffffbfff131b08e R10: fffffbfff131b08e R11: 0000000000000000 R12: 0000000000000282 R13: dffffc0000000000 R14: dffffc0000000000 R15: ffff8880a8e94a4c rcu_read_unlock include/linux/rcupdate.h:688 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:411 [inline] batadv_nc_worker+0x261/0x5c0 net/batman-adv/network-coding.c:718 process_one_work+0x789/0xfc0 kernel/workqueue.c:2269 worker_thread+0xaa4/0x1460 kernel/workqueue.c:2415 kthread+0x37e/0x3a0 drivers/block/aoe/aoecmd.c:1234 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 rcu: rcu_preempt kthread starved for 10486 jiffies! g114061 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1 rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior. rcu: RCU grace-period kthread stack dump: rcu_preempt I28608 10 2 0x00004000 Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0x979/0xce0 kernel/sched/core.c:4527 --- This report is generated by a bot. 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