INFO: task syz-executor.2:8659 blocked for more than 143 seconds. Not tainted 5.10.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.2 state:D stack:23640 pid: 8659 ppid: 1 flags:0x20004004 Call Trace: context_switch kernel/sched/core.c:4327 [inline] __schedule+0x8eb/0x21b0 kernel/sched/core.c:5078 schedule+0xcf/0x270 kernel/sched/core.c:5157 rwsem_down_write_slowpath+0x809/0x1220 kernel/locking/rwsem.c:1106 __down_write_common kernel/locking/rwsem.c:1261 [inline] __down_write_common kernel/locking/rwsem.c:1258 [inline] __down_write kernel/locking/rwsem.c:1270 [inline] down_write+0x132/0x150 kernel/locking/rwsem.c:1407 fuse_mount_remove fs/fuse/inode.c:1531 [inline] fuse_kill_sb_anon+0x81/0x290 fs/fuse/inode.c:1566 deactivate_locked_super+0x94/0x160 fs/super.c:335 deactivate_super+0xad/0xd0 fs/super.c:366 cleanup_mnt+0x3a3/0x530 fs/namespace.c:1118 task_work_run+0xdd/0x190 kernel/task_work.c:168 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:174 [inline] exit_to_user_mode_prepare+0x1f0/0x200 kernel/entry/common.c:201 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:302 __do_fast_syscall_32+0x62/0x80 arch/x86/entry/common.c:138 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:160 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf7fba549 RSP: 002b:00000000090bed1c EFLAGS: 00000212 ORIG_RAX: 0000000000000034 RAX: 0000000000000000 RBX: 00000000090bedac RCX: 0000000000000002 RDX: 0000000009775228 RSI: 0000000009775270 RDI: 00000000080d8e62 RBP: 00000000090bedac R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by khungtaskd/1637: #0: ffffffff8b78e120 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x28c kernel/locking/lockdep.c:6254 1 lock held by systemd-journal/4889: 1 lock held by in:imklog/8192: #0: ffff88801b8d2ff0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:947 2 locks held by syz-executor.2/8659: #0: ffff88801ffba0e0 (&type->s_umount_key#50){+.+.}-{3:3}, at: deactivate_super+0xa5/0xd0 fs/super.c:365 #1: ffff888023cc2338 (&fc->killsb){++++}-{3:3}, at: fuse_mount_remove fs/fuse/inode.c:1531 [inline] #1: ffff888023cc2338 (&fc->killsb){++++}-{3:3}, at: fuse_kill_sb_anon+0x81/0x290 fs/fuse/inode.c:1566 1 lock held by syz-executor.2/16749: #0: ffff888023cc2338 (&fc->killsb){++++}-{3:3}, at: fuse_notify_retrieve fs/fuse/dev.c:1743 [inline] #0: ffff888023cc2338 (&fc->killsb){++++}-{3:3}, at: fuse_notify fs/fuse/dev.c:1781 [inline] #0: ffff888023cc2338 (&fc->killsb){++++}-{3:3}, at: fuse_dev_do_write+0xfdd/0x2c10 fs/fuse/dev.c:1859 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1637 Comm: khungtaskd Not tainted 5.10.0-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+0x107/0x163 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x3c/0xef lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline] watchdog+0xe36/0x10b0 kernel/hung_task.c:294 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 8 Comm: kworker/u4:0 Not tainted 5.10.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet RIP: 0010:iterate_chain_key kernel/locking/lockdep.c:418 [inline] RIP: 0010:__lock_acquire+0xc45/0x54b0 kernel/locking/lockdep.c:4820 Code: 40 00 0f 84 59 0d 00 00 0f b7 44 24 38 8b 4c 24 48 8b 5c 24 58 c1 e0 0d 66 0b 44 24 08 98 2b 44 24 60 33 44 24 50 89 c2 29 c1 <01> d8 c1 c2 06 31 ca 89 d1 29 d3 01 c2 c1 c1 08 31 d9 89 ce 29 c8 RSP: 0018:ffffc90000cd7970 EFLAGS: 00000013 RAX: 00000000ea9c93d7 RBX: 00000000f597d5a1 RCX: 00000000721fbedc RDX: 00000000ea9c93d7 RSI: 0000000000000008 RDI: ffffffff8f4fbd00 RBP: ffff88801151d040 R08: 0000000000000000 R09: ffffffff8f4f97a7 R10: fffffbfff1e9f2f4 R11: 0000000000000000 R12: ffff88801151da40 R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8a7a8f8000 CR3: 00000000266a3000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire kernel/locking/lockdep.c:5437 [inline] lock_acquire+0x29d/0x750 kernel/locking/lockdep.c:5402 rcu_lock_acquire include/linux/rcupdate.h:253 [inline] rcu_read_lock include/linux/rcupdate.h:642 [inline] batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:754 [inline] batadv_iv_ogm_schedule_buff+0x640/0x14d0 net/batman-adv/bat_iv_ogm.c:825 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:869 [inline] batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:862 [inline] batadv_iv_send_outstanding_bat_ogm_packet+0x659/0x8f0 net/batman-adv/bat_iv_ogm.c:1723 process_one_work+0x98d/0x1630 kernel/workqueue.c:2275 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296