syzbot


INFO: task hung in hci_cmd_sync_clear

Status: auto-obsoleted due to no activity on 2024/06/24 21:55
Reported-by: syzbot+46e0ab4df458bcc7f7fc@syzkaller.appspotmail.com
First crash: 100d, last: 100d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in hci_cmd_sync_clear bluetooth 4 676d 823d 0/27 auto-obsoleted due to no activity on 2022/11/16 14:10
upstream INFO: task hung in hci_cmd_sync_clear (2) bluetooth 15 91d 497d 0/27 auto-obsoleted due to no activity on 2024/06/23 16:01

Sample crash report:
INFO: task syz-executor.2:5177 blocked for more than 143 seconds.
      Not tainted 6.1.82-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2  state:D stack:26072 pid:5177  ppid:3589   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 schedule_timeout+0xac/0x300 kernel/time/timer.c:1911
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x350/0x610 kernel/sched/completion.c:138
 __flush_work+0x95b/0xad0 kernel/workqueue.c:3076
 __cancel_work_timer+0x519/0x6a0 kernel/workqueue.c:3163
 hci_cmd_sync_clear+0x2c/0x220 net/bluetooth/hci_sync.c:640
 hci_unregister_dev+0x14d/0x4d0 net/bluetooth/hci_core.c:2731
 vhci_release+0x7f/0xd0 drivers/bluetooth/hci_vhci.c:573
 __fput+0x3b7/0x890 fs/file_table.c:320
 task_work_run+0x246/0x300 kernel/task_work.c:179
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0xa73/0x26a0 kernel/exit.c:869
 do_group_exit+0x202/0x2b0 kernel/exit.c:1019
 get_signal+0x16f7/0x17d0 kernel/signal.c:2862
 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:168
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:297
 ret_from_fork+0x15/0x30 arch/x86/entry/entry_64.S:300
RIP: 0033:0x7fd893c7dda9
RSP: 002b:00007fd894a8a078 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: 0000000000000000 RBX: 00007fd893dabf80 RCX: 00007fd893c7dda9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fd893cca47a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fd893dabf80 R15: 00007ffd8c0bee38
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8d12ab10 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8d12b310 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516
1 lock held by khungtaskd/28:
 #0: ffffffff8d12a940 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:319 [inline]
 #0: ffffffff8d12a940 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:760 [inline]
 #0: ffffffff8d12a940 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6494
4 locks held by klogd/2990:
 #0: ffff8880b983aa18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537
 #1: ffff8880b9827788 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x43d/0x770 kernel/sched/psi.c:1000
 #2: ffff88807f3fa7d8 (&p->pi_lock){-.-.}-{2:2}, at: try_to_wake_up+0xad/0x12e0 kernel/sched/core.c:4112
 #3: ffff8880b983aa18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537
1 lock held by udevd/3001:
 #0: ffff8880b983aa18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537
2 locks held by getty/3300:
 #0: ffff88814b4d0098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
 #1: ffffc900031262f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2188
3 locks held by kworker/u5:4/3593:
 #0: ffff888076952138 ((wq_completion)hci3){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc90004c1fd20 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #2: ffff88807e06d0b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_cmd_sync_work+0x1dc/0x400 net/bluetooth/hci_sync.c:304
3 locks held by kworker/1:5/3629:
 #0: ffff88814b68e138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc9000510fd20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #2: ffffffff8e298fe8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x16b0 net/ipv6/addrconf.c:4113
3 locks held by kworker/0:7/3637:
 #0: ffff88814b68e138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc9000513fd20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #2: ffffffff8e298fe8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x16b0 net/ipv6/addrconf.c:4113
2 locks held by kworker/0:11/3930:
 #0: ffff888012472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc900057f7d20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
3 locks held by kworker/0:0/19568:
 #0: ffff888012470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc900033ffd20 (xfrm_state_gc_work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #2: ffffffff8d12ff38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
 #2: ffffffff8d12ff38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3b0/0x8a0 kernel/rcu/tree_exp.h:949
3 locks held by kworker/u4:0/23702:
 #0: ffff888012616938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc9000705fd20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #2: ffffffff8e28cd90 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf1/0xb60 net/core/net_namespace.c:563
3 locks held by kworker/1:1/29709:
 #0: ffff888012470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc9000327fd20 (fqdir_free_work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #2: ffffffff8d12fe00 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x48/0x5f0 kernel/rcu/tree.c:4018
2 locks held by syz-executor.3/3606:
 #0: ffffffff8e298fe8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8e298fe8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118
 #1: ffff88807c0693e8 (&wg->device_update_lock){+.+.}-{3:3}, at: wg_open+0x224/0x410 drivers/net/wireguard/device.c:49
2 locks held by syz-executor.4/4193:
 #0: ffff8880950ab210 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #0: ffff8880950ab210 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: __sock_release net/socket.c:653 [inline]
 #0: ffff8880950ab210 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: sock_close+0x98/0x230 net/socket.c:1400
 #1: ffffffff8d12ff38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline]
 #1: ffffffff8d12ff38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x479/0x8a0 kernel/rcu/tree_exp.h:949
1 lock held by syz-executor.2/4203:
 #0: ffff888074ccb810 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #0: ffff888074ccb810 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: __sock_release net/socket.c:653 [inline]
 #0: ffff888074ccb810 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: sock_close+0x98/0x230 net/socket.c:1400
1 lock held by syz-executor.1/4210:
 #0: ffff888074c45010 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #0: ffff888074c45010 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: __sock_release net/socket.c:653 [inline]
 #0: ffff888074c45010 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: sock_close+0x98/0x230 net/socket.c:1400
5 locks held by syz-executor.0/4237:

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.82-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1b0/0x3f0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
 watchdog+0xf88/0xfd0 kernel/hung_task.c:377
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:307
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 151 Comm: kworker/1:2 Not tainted 6.1.82-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
Workqueue: rcu_gp process_srcu
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:203
Code: e8 25 00 00 00 0f 0b 0f 1f 00 53 48 89 fb e8 17 00 00 00 48 8b 3d 58 e1 e8 0c 48 89 de 5b e9 37 9e 56 00 cc cc cc cc cc cc cc <48> 8b 04 24 65 48 8b 0d a4 eb 77 7e 65 8b 15 a5 eb 77 7e f7 c2 00
RSP: 0000:ffffc9000264fb40 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffffffff91d5ba20 RCX: ffff8880177e8000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffffff91d5ba28 R08: ffffffff81596973 R09: fffffbfff23ab745
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: dffffc0000000000 R14: 0000000000000008 R15: ffff888012472000
FS:  0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f81db4efee6 CR3: 000000000ce8e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 __queue_delayed_work+0x182/0x210 kernel/workqueue.c:1668
 queue_delayed_work_on+0x156/0x250 kernel/workqueue.c:1704
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:307
 </TASK>
vkms_vblank_simulate: vblank timer overrun

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/03/16 21:54 linux-6.1.y d7543167affd d615901c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in hci_cmd_sync_clear
* Struck through repros no longer work on HEAD.