INFO: task syz-executor.3:8576 blocked for more than 143 seconds. Not tainted 6.8.0-rc7-syzkaller-00051-g67be068d31d4 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.3 state:D stack:20408 pid:8576 tgid:8576 ppid:1 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5400 [inline] __schedule+0x177f/0x49a0 kernel/sched/core.c:6727 __schedule_loop kernel/sched/core.c:6802 [inline] schedule+0x149/0x260 kernel/sched/core.c:6817 schedule_timeout+0xb0/0x310 kernel/time/timer.c:2159 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion+0x354/0x620 kernel/sched/completion.c:148 btrfs_qgroup_wait_for_completion+0x92/0xc0 fs/btrfs/qgroup.c:3849 close_ctree+0x118/0xd40 fs/btrfs/disk-io.c:4254 generic_shutdown_super+0x136/0x2d0 fs/super.c:641 kill_anon_super+0x3b/0x70 fs/super.c:1225 btrfs_kill_super+0x41/0x50 fs/btrfs/super.c:2093 deactivate_locked_super+0xc4/0x130 fs/super.c:472 cleanup_mnt+0x426/0x4c0 fs/namespace.c:1267 task_work_run+0x24e/0x310 kernel/task_work.c:180 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:108 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:201 [inline] syscall_exit_to_user_mode+0x167/0x360 kernel/entry/common.c:212 do_syscall_64+0x108/0x240 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x6f/0x77 RIP: 0033:0x7f111f67f0d7 RSP: 002b:00007ffdcb9001a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f111f67f0d7 RDX: 0000000000000000 RSI: 000000000000000a RDI: 00007ffdcb900260 RBP: 00007ffdcb900260 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffdcb901320 R13: 00007f111f6c93b9 R14: 000000000015da3a R15: 0000000000000004 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8e130be0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #0: ffffffff8e130be0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #0: ffffffff8e130be0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 2 locks held by kworker/u4:2/34: 2 locks held by getty/4820: #0: ffff88802b3b20a0 (&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 1 lock held by syz-executor.3/8576: #0: ffff88807e0b40e0 (&type->s_umount_key#62){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88807e0b40e0 (&type->s_umount_key#62){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88807e0b40e0 (&type->s_umount_key#62){++++}-{3:3}, at: deactivate_super+0xb5/0xf0 fs/super.c:504 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted 6.8.0-rc7-syzkaller-00051-g67be068d31d4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 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+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:243 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 27824 Comm: syz-executor.0 Not tainted 6.8.0-rc7-syzkaller-00051-g67be068d31d4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 RIP: 0010:__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] RIP: 0010:_raw_spin_lock+0x29/0x40 kernel/locking/spinlock.c:154 Code: 90 f3 0f 1e fa 53 48 89 fb bf 01 00 00 00 e8 6e 34 fb f5 48 8d 7b 18 31 f6 31 d2 31 c9 41 b8 01 00 00 00 45 31 c9 ff 74 24 08 e2 fe 07 f6 48 83 c4 08 48 89 df 5b e9 85 5f 09 f6 0f 1f 44 00 RSP: 0018:ffffc900161b7b28 EFLAGS: 00000246 RAX: 1ffff110046f964d RBX: ffff88802a736480 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88802a736498 RBP: ffffc900161b7c30 R08: 0000000000000001 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffed10046f93b9 R12: ffff88802a736000 R13: 0000000000000001 R14: dffffc0000000000 R15: 0000000000000000 FS: 00007f6a76fbf6c0(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c00d627000 CR3: 0000000030948000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: spin_lock include/linux/spinlock.h:351 [inline] io_cq_lock io_uring/io_uring.c:648 [inline] __io_cqring_overflow_flush+0x156/0x610 io_uring/io_uring.c:701 io_cqring_do_overflow_flush io_uring/io_uring.c:727 [inline] io_cqring_wait io_uring/io_uring.c:2670 [inline] __do_sys_io_uring_enter io_uring/io_uring.c:3701 [inline] __se_sys_io_uring_enter+0x1f45/0x2b50 io_uring/io_uring.c:3591 do_syscall_64+0xf9/0x240 entry_SYSCALL_64_after_hwframe+0x6f/0x77 RIP: 0033:0x7f6a7627dda9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f6a76fbf0c8 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: ffffffffffffffda RBX: 00007f6a763abf80 RCX: 00007f6a7627dda9 RDX: 0000000000400000 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 00007f6a762ca47a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f6a763abf80 R15: 00007ffe64a08ac8