INFO: task syz-executor.0:6655 blocked for more than 147 seconds. Not tainted 6.8.0-rc2-next-20240202-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:24632 pid:6655 tgid:6655 ppid:5092 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5400 [inline] __schedule+0x17df/0x4a40 kernel/sched/core.c:6727 __schedule_loop kernel/sched/core.c:6804 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6819 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+0x355/0x620 kernel/sched/completion.c:148 __flush_workqueue+0x730/0x1630 kernel/workqueue.c:3617 drain_workqueue+0xc9/0x390 kernel/workqueue.c:3730 destroy_workqueue+0xba/0xc40 kernel/workqueue.c:5319 hci_release_dev+0x136/0x1670 net/bluetooth/hci_core.c:2807 bt_host_release+0x83/0x90 net/bluetooth/hci_sysfs.c:94 device_release+0x99/0x1c0 kobject_cleanup lib/kobject.c:682 [inline] kobject_release lib/kobject.c:716 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x1f5/0x430 lib/kobject.c:733 hci_uart_tty_close+0x1c1/0x290 drivers/bluetooth/hci_ldisc.c:552 tty_ldisc_kill+0xa3/0x1a0 drivers/tty/tty_ldisc.c:607 tty_ldisc_release+0x1a1/0x200 drivers/tty/tty_ldisc.c:775 tty_release_struct+0x2b/0xe0 drivers/tty/tty_io.c:1696 tty_release+0xd0c/0x12c0 drivers/tty/tty_io.c:1867 __fput+0x429/0x8a0 fs/file_table.c:376 __do_sys_close fs/open.c:1554 [inline] __se_sys_close fs/open.c:1539 [inline] __x64_sys_close+0x7f/0x110 fs/open.c:1539 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 RIP: 0033:0x7f0f79a7cc9a RSP: 002b:00007ffc02b44130 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f0f79a7cc9a RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007f0f79bad980 R08: 0000001b31f20000 R09: 0000000000000420 R10: 000000008135fff4 R11: 0000000000000293 R12: 0000000000046ad1 R13: ffffffffffffffff R14: 00007f0f79600000 R15: 0000000000046790 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8e130d60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #0: ffffffff8e130d60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #0: ffffffff8e130d60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 3 locks held by kworker/u4:2/34: 1 lock held by udevd/4520: #0: ffff8880b953c758 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:559 2 locks held by getty/4817: #0: ffff88802a3f70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900031432f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b5/0x1e10 drivers/tty/n_tty.c:2201 3 locks held by syz-executor.4/5095: 2 locks held by kworker/1:4/5147: 2 locks held by syz-executor.0/6655: #0: ffff88802d1740a0 (&tty->ldisc_sem){++++}-{0:0}, at: __tty_ldisc_lock drivers/tty/tty_ldisc.c:289 [inline] #0: ffff88802d1740a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_lock_pair_timeout drivers/tty/tty_ldisc.c:345 [inline] #0: ffff88802d1740a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_lock_pair drivers/tty/tty_ldisc.c:366 [inline] #0: ffff88802d1740a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_release+0xb7/0x200 drivers/tty/tty_ldisc.c:774 #1: ffff888078e2f0a0 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: __tty_ldisc_lock_nested drivers/tty/tty_ldisc.c:295 [inline] #1: ffff888078e2f0a0 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: tty_ldisc_lock_pair_timeout drivers/tty/tty_ldisc.c:347 [inline] #1: ffff888078e2f0a0 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: tty_ldisc_lock_pair drivers/tty/tty_ldisc.c:366 [inline] #1: ffff888078e2f0a0 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: tty_ldisc_release+0xdb/0x200 drivers/tty/tty_ldisc.c:774 3 locks held by syz-executor.4/7261: 1 lock held by syz-executor.3/7476: #0: ffffffff8e135fc0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x550 kernel/rcu/tree.c:4073 3 locks held by syz-executor.2/7504: #0: ffff888052243810 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:802 [inline] #0: ffff888052243810 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline] #0: ffff888052243810 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1421 #1: ffff88801b6d1270 (sk_lock-AF_QIPCRTR){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1691 [inline] #1: ffff88801b6d1270 (sk_lock-AF_QIPCRTR){+.+.}-{0:0}, at: qrtr_release+0x54/0x2a0 net/qrtr/af_qrtr.c:1213 #2: ffffffff8e1360f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #2: ffffffff8e1360f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x39a/0x820 kernel/rcu/tree_exp.h:939 3 locks held by syz-executor.1/7505: #0: ffff88803aecac10 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:802 [inline] #0: ffff88803aecac10 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline] #0: ffff88803aecac10 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1421 #1: ffff8880758106f0 (sk_lock-AF_QIPCRTR){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1691 [inline] #1: ffff8880758106f0 (sk_lock-AF_QIPCRTR){+.+.}-{0:0}, at: qrtr_release+0x54/0x2a0 net/qrtr/af_qrtr.c:1213 #2: ffffffff8e1360f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #2: ffffffff8e1360f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x463/0x820 kernel/rcu/tree_exp.h:939 2 locks held by syz-executor.0/7509: 6 locks held by syz-executor.4/7513: #0: ffff88802c232fc8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x259/0x320 fs/file.c:1191 #1: ffff88801f464420 (sb_writers#10){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2801 [inline] #1: ffff88801f464420 (sb_writers#10){.+.+}-{0:0}, at: vfs_writev+0x2d9/0xbb0 fs/read_write.c:969 #2: ffff88802be57088 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1eb/0x500 fs/kernfs/file.c:325 #3: ffffffff8e15aa88 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_lock include/linux/cgroup.h:368 [inline] #3: ffffffff8e15aa88 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_kn_lock_live+0xe6/0x290 kernel/cgroup/cgroup.c:1662 #4: ffffffff8dfcc7f0 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2413 [inline] #4: ffffffff8dfcc7f0 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_procs_write_start+0x1a0/0x660 kernel/cgroup/cgroup.c:2917 #5: ffffffff8e15ac70 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2415 [inline] #5: ffffffff8e15ac70 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_procs_write_start+0x1b5/0x660 kernel/cgroup/cgroup.c:2917 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.8.0-rc2-next-20240202-syzkaller #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+0xfb0/0xff0 kernel/hung_task.c:379 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:242 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 34 Comm: kworker/u4:2 Not tainted 6.8.0-rc2-next-20240202-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Workqueue: netns cleanup_net RIP: 0010:__might_resched+0x7d/0x780 kernel/sched/core.c:10133 Code: 8d 48 c7 44 24 50 d0 a3 66 81 4c 8d 7c 24 40 49 c1 ef 03 48 b8 f1 f1 f1 f1 00 f2 f2 f2 49 89 04 0f 41 c7 44 0f 09 f2 f2 f2 00 <66> 41 c7 44 0f 0d f3 f3 41 c6 44 0f 0f f3 e8 20 2c 06 0a 85 c0 74 RSP: 0018:ffffc90000aa78e0 EFLAGS: 00000a06 RAX: f2f2f200f1f1f1f1 RBX: 000000000004e09f RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000114 RDI: ffffffff8ca8e620 RBP: ffffc90000aa79f0 R08: ffffffff8f85b72f R09: 1ffffffff1f0b6e5 R10: dffffc0000000000 R11: fffffbfff1f0b6e6 R12: 0000000000000000 R13: 000000000004e09e R14: 0000000000000114 R15: 1ffff92000154f24 FS: 0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005555567c9978 CR3: 000000007fbde000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: inet_twsk_purge+0x137/0xb80 net/ipv4/inet_timewait_sock.c:276 ops_exit_list net/core/net_namespace.c:175 [inline] cleanup_net+0x775/0xb90 net/core/net_namespace.c:618 process_one_work kernel/workqueue.c:3049 [inline] process_scheduled_works+0x913/0x14f0 kernel/workqueue.c:3125 worker_thread+0xa60/0x1000 kernel/workqueue.c:3206 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:242