INFO: task syz-executor.5:5087 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.5 state:D stack:20304 pid:5087 tgid:5087 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: 0033:0x7f2ac667e057 RSP: 002b:00007ffd8798eee8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f2ac667e057 RDX: 0000000000000000 RSI: 000000000000000a RDI: 00007ffd8798efa0 RBP: 00007ffd8798efa0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd87990060 R13: 00007f2ac66c83b9 R14: 0000000000105d20 R15: 0000000000000010 Showing all locks held in the system: 6 locks held by kworker/u4:1/12: #0: ffff888141e59d38 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2602 [inline] #0: ffff888141e59d38 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2700 #1: ffffc90000117d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2602 [inline] #1: ffffc90000117d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2700 #2: ffff88803e74eb98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_read fs/ext4/ext4.h:1767 [inline] #2: ffff88803e74eb98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x1bd/0x3e0 fs/ext4/inode.c:2773 #3: ffff888075da4888 (&ei->i_data_sem){++++}-{3:3}, at: ext4_map_blocks+0x959/0x1cd0 fs/ext4/inode.c:614 #4: ffff8880b993c358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:558 #5: ffff8880b9928808 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: update_rq_clock_task kernel/sched/core.c:725 [inline] #5: ffff8880b9928808 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: update_rq_clock+0x22b/0x890 kernel/sched/core.c:769 3 locks held by kworker/1:0H/24: 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/u4:5/752: #0: ffff8880b993c358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:558 #1: ffff8880b9928808 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x441/0x770 kernel/sched/psi.c:988 #2: ffff88801d2468d8 (&lo->lo_work_lock){..-.}-{2:2}, at: spin_lock_irq include/linux/spinlock.h:376 [inline] #2: ffff88801d2468d8 (&lo->lo_work_lock){..-.}-{2:2}, at: loop_process_work+0x1dec/0x22a0 drivers/block/loop.c:1953 #3: ffff8880b993c358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:558 2 locks held by getty/4807: #0: ffff88802a89a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900031332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b4/0x1e10 drivers/tty/n_tty.c:2201 2 locks held by syz-executor.5/5087: #0: ffff888076df00e0 (&type->s_umount_key#30){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff888076df00e0 (&type->s_umount_key#30){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff888076df00e0 (&type->s_umount_key#30){++++}-{3:3}, at: deactivate_super+0xad/0xf0 fs/super.c:516 #1: ffff888141b6c7d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:364 [inline] #1: ffff888141b6c7d0 (&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: 752 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:batadv_has_timed_out net/batman-adv/main.h:281 [inline] RIP: 0010:batadv_nc_worker+0x3cc/0x610 net/batman-adv/network-coding.c:727 Code: 0f b6 04 38 84 c0 0f 85 ff 01 00 00 8b 7d 00 e8 7a e0 95 f6 48 89 c5 4c 01 f5 48 c7 c0 00 f2 60 8d 48 c1 e8 03 42 80 3c 38 00 <74> 0c 48 c7 c7 00 f2 60 8d e8 b6 1e 04 f7 48 8b 1d 7f 90 7a 02 48 RSP: 0018:ffffc90003fefb98 EFLAGS: 00000246 RAX: 1ffffffff1ac1e40 RBX: ffff888037f2d798 RCX: ffff88801cd15940 RDX: 0000000000000000 RSI: 000000000000000a RDI: 0000000000000000 RBP: 0000000100016674 R08: ffffffff817c41e5 R09: 1ffffffff21bb087 R10: dffffc0000000000 R11: fffffbfff21bb088 R12: ffff888037f2cc80 R13: 1ffff11006fe5af3 R14: 0000000100016673 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055e3a16a3708 CR3: 000000000d731000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: 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