Hello, syzbot found the following issue on: HEAD commit: e8f60cd7db24 Merge tag 'perf-tools-fixes-for-v6.2-2-2023-0.. git tree: upstream console+strace: https://syzkaller.appspot.com/x/log.txt?x=13182686480000 kernel config: https://syzkaller.appspot.com/x/.config?x=ebc110f9741920ed dashboard link: https://syzkaller.appspot.com/bug?extid=4fec87c399346da35903 compiler: Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12ef7fba480000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15c68186480000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/bfa9ef2acc71/disk-e8f60cd7.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/718a64154ab8/vmlinux-e8f60cd7.xz kernel image: https://storage.googleapis.com/syzbot-assets/616a25151c23/bzImage-e8f60cd7.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/099f2b1a07ee/mount_0.gz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+4fec87c399346da35903@xxxxxxxxxxxxxxxxxxxxxxxxx INFO: task kworker/1:3:4767 blocked for more than 143 seconds. Not tainted 6.2.0-rc3-syzkaller-00030-ge8f60cd7db24 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:3 state:D stack:22656 pid:4767 ppid:2 flags:0x00004000 Workqueue: events_long flush_mdb Call Trace: <TASK> context_switch kernel/sched/core.c:5244 [inline] __schedule+0x995/0xe20 kernel/sched/core.c:6555 schedule+0xcb/0x190 kernel/sched/core.c:6631 io_schedule+0x83/0x100 kernel/sched/core.c:8811 bit_wait_io+0xe/0xc0 kernel/sched/wait_bit.c:209 __wait_on_bit_lock+0xbb/0x1a0 kernel/sched/wait_bit.c:90 out_of_line_wait_on_bit_lock+0x1c3/0x240 kernel/sched/wait_bit.c:117 lock_buffer include/linux/buffer_head.h:397 [inline] hfs_mdb_commit+0xacd/0xf80 fs/hfs/mdb.c:325 process_one_work+0x877/0xdb0 kernel/workqueue.c:2289 worker_thread+0xb14/0x1330 kernel/workqueue.c:2436 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 </TASK> Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d326f50 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x30/0xd00 kernel/rcu/tasks.h:507 1 lock held by rcu_tasks_trace/13: #0: ffffffff8d327750 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x30/0xd00 kernel/rcu/tasks.h:507 1 lock held by khungtaskd/28: #0: ffffffff8d326d80 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by kworker/0:2/898: #0: ffff888012872538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7f2/0xdb0 #1: ffffc90004e87d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x831/0xdb0 kernel/workqueue.c:2264 2 locks held by getty/4745: #0: ffff88802839c098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc900015802f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x53b/0x1650 drivers/tty/n_tty.c:2177 2 locks held by kworker/1:3/4767: #0: ffff888012871538 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x7f2/0xdb0 #1: ffffc900038efd00 ((work_completion)(&(&sbi->mdb_work)->work)){+.+.}-{0:0}, at: process_one_work+0x831/0xdb0 kernel/workqueue.c:2264 2 locks held by syz-executor208/15791: #0: ffff88807c1a0928 (&type->i_mutex_dir_key#6){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline] #0: ffff88807c1a0928 (&type->i_mutex_dir_key#6){+.+.}-{3:3}, at: lock_mount+0x5f/0x2d0 fs/namespace.c:2397 #1: ffffffff8d32c3f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:292 [inline] #1: ffffffff8d32c3f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x384/0x860 kernel/rcu/tree_exp.h:946 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.2.0-rc3-syzkaller-00030-ge8f60cd7db24 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1b1/0x290 lib/dump_stack.c:106 nmi_cpu_backtrace+0x46f/0x4f0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1ba/0x420 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xcd5/0xd20 kernel/hung_task.c:377 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 </TASK> Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 75 Comm: kworker/u4:4 Not tainted 6.2.0-rc3-syzkaller-00030-ge8f60cd7db24 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Workqueue: events_unbound flush_memcg_stats_dwork RIP: 0010:trace_lock_acquire+0x66/0x260 include/trace/events/lock.h:24 Code: 0d 0f 86 a4 00 00 00 89 ed 48 89 e8 48 c1 e8 06 48 8d 3c c5 a8 67 96 8e be 08 00 00 00 e8 62 79 76 00 48 0f a3 2d 72 5a 2b 0d <73> 3d 65 ff 05 09 8b 98 7e 48 c7 c0 80 d2 82 8e 48 c1 e8 03 80 3c RSP: 0018:ffffc90001597778 EFLAGS: 00000057 RAX: 0000000000000001 RBX: dffffc0000000000 RCX: ffffffff816b0d2e RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8e9667a8 RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff1d2ccf6 R10: fffffbfff1d2ccf6 R11: 1ffffffff1d2ccf5 R12: dffffc0000000000 R13: 1ffff920002b2efc R14: 0000000000000001 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4bb7e5cc00 CR3: 000000000d08e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> lock_acquire+0xa4/0x3c0 kernel/locking/lockdep.c:5639 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xb3/0x100 kernel/locking/spinlock.c:162 debug_object_activate+0x96/0x6e0 lib/debugobjects.c:665 debug_timer_activate kernel/time/timer.c:782 [inline] __mod_timer+0x837/0xcf0 kernel/time/timer.c:1119 queue_delayed_work_on+0x125/0x210 kernel/workqueue.c:1701 process_one_work+0x877/0xdb0 kernel/workqueue.c:2289 worker_thread+0xb14/0x1330 kernel/workqueue.c:2436 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 </TASK> --- 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@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. syzbot can test patches for this issue, for details see: https://goo.gl/tpsmEJ#testing-patches
