INFO: task syz-executor.1:5107 blocked for more than 143 seconds. Not tainted 6.7.0-rc8-syzkaller-00177-g52b1853b080a #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:19280 pid:5107 tgid:5107 ppid:1 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5376 [inline] __schedule+0x1961/0x4ab0 kernel/sched/core.c:6688 __schedule_loop kernel/sched/core.c:6763 [inline] schedule+0x149/0x260 kernel/sched/core.c:6778 wb_wait_for_completion+0x166/0x290 fs/fs-writeback.c:192 sync_inodes_sb+0x293/0xb20 fs/fs-writeback.c:2758 sync_filesystem+0x16f/0x220 fs/sync.c:64 generic_shutdown_super+0x72/0x2c0 fs/super.c:669 kill_block_super+0x44/0x90 fs/super.c:1667 ext4_kill_sb+0x68/0xa0 fs/ext4/super.c:7330 deactivate_locked_super+0xc1/0x130 fs/super.c:484 cleanup_mnt+0x426/0x4c0 fs/namespace.c:1256 task_work_run+0x24a/0x300 kernel/task_work.c:180 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:171 exit_to_user_mode_prepare+0xb1/0x150 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x69/0x2a0 kernel/entry/common.c:296 do_syscall_64+0x52/0x110 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7faaa527e057 RSP: 002b:00007ffcd5c3d4c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007faaa527e057 RDX: 0000000000000000 RSI: 000000000000000a RDI: 00007ffcd5c3d580 RBP: 00007ffcd5c3d580 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffcd5c3e640 R13: 00007faaa52c83b9 R14: 000000000004a76d R15: 0000000000000012 Showing all locks held in the system: 2 locks held by ksoftirqd/0/16: #0: ffff8880b983c358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:558 #1: ffffffff8d9476c8 (tk_core.seq.seqcount){----}-{0:0}, at: psi_task_switch+0x441/0x770 kernel/sched/psi.c:988 1 lock held by khungtaskd/29: #0: ffffffff8d92dae0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:301 [inline] #0: ffffffff8d92dae0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline] #0: ffffffff8d92dae0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 4 locks held by kworker/u4:6/1072: 2 locks held by getty/4813: #0: ffff88802a5520a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900015972f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b4/0x1e10 drivers/tty/n_tty.c:2201 2 locks held by syz-executor.1/5107: #0: ffff888029cd20e0 (&type->s_umount_key#31){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff888029cd20e0 (&type->s_umount_key#31){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff888029cd20e0 (&type->s_umount_key#31){++++}-{3:3}, at: deactivate_super+0xad/0xf0 fs/super.c:516 #1: ffff88801cd447d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:364 [inline] #1: ffff88801cd447d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x274/0xb20 fs/fs-writeback.c:2756 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.7.0-rc8-syzkaller-00177-g52b1853b080a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x498/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x310 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xfaf/0xff0 kernel/hung_task.c:379 kthread+0x2d3/0x370 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 137 Comm: kworker/u4:5 Not tainted 6.7.0-rc8-syzkaller-00177-g52b1853b080a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Workqueue: bat_events batadv_nc_worker RIP: 0010:__lock_acquire+0x358/0x1fd0 kernel/locking/lockdep.c:5072 Code: 89 df e8 4b 52 7d 00 4c 8b 44 24 08 48 be 00 00 00 00 00 fc ff df 48 89 2b 48 8b 6c 24 28 49 8d 5c e8 10 48 89 d8 48 c1 e8 03 <80> 3c 30 00 74 17 48 89 df e8 1a 52 7d 00 4c 8b 44 24 08 48 be 00 RSP: 0018:ffffc90002ddf930 EFLAGS: 00000802 RAX: 1ffff11002a79c8c RBX: ffff8880153ce460 RCX: ffffffff925d0303 RDX: 0000000000000002 RSI: dffffc0000000000 RDI: 0000000000000020 RBP: 000000000000000a R08: ffff8880153ce400 R09: 0000000000000000 R10: dffffc0000000000 R11: fffffbfff1e01886 R12: ffffffff8d92dae0 R13: 0000000000000020 R14: 000000000000000a R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c000d7f000 CR3: 000000000d731000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754 rcu_lock_acquire include/linux/rcupdate.h:301 [inline] rcu_read_lock include/linux/rcupdate.h:747 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xec/0x610 net/batman-adv/network-coding.c:719 process_one_work kernel/workqueue.c:2627 [inline] process_scheduled_works+0x90f/0x1420 kernel/workqueue.c:2700 worker_thread+0xa5f/0x1000 kernel/workqueue.c:2781 kthread+0x2d3/0x370 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242