Bluetooth: hci2 command 0x0419 tx timeout Bluetooth: hci2 command 0x0409 tx timeout Bluetooth: hci2 command 0x041b tx timeout Bluetooth: hci2 command 0x040f tx timeout Bluetooth: hci2 command 0x0419 tx timeout INFO: task kworker/u4:5:8944 blocked for more than 140 seconds. Not tainted 4.14.226-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:5 D26520 8944 2 0x80000000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3384 schedule+0x8d/0x1b0 kernel/sched/core.c:3428 schedule_timeout+0x80a/0xe90 kernel/time/timer.c:1724 do_wait_for_common kernel/sched/completion.c:91 [inline] __wait_for_common kernel/sched/completion.c:112 [inline] wait_for_common+0x272/0x430 kernel/sched/completion.c:123 flush_workqueue+0x3ce/0x1310 kernel/workqueue.c:2676 flush_scheduled_work include/linux/workqueue.h:578 [inline] tipc_exit_net+0x38/0x60 net/tipc/core.c:96 ops_exit_list+0xa5/0x150 net/core/net_namespace.c:142 cleanup_net+0x3b3/0x840 net/core/net_namespace.c:484 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Showing all locks held in the system: 1 lock held by khungtaskd/1508: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 3 locks held by kworker/u4:5/8944: #0: ("%s""netns"){+.+.}, at: [] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087 #1: (net_cleanup_work){+.+.}, at: [] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091 #2: (net_mutex){+.+.}, at: [] cleanup_net+0x110/0x840 net/core/net_namespace.c:450 3 locks held by kworker/1:3/9021: #0: ("events"){+.+.}, at: [] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087 #1: ((&smc->tcp_listen_work)){+.+.}, at: [] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091 #2: (&smc->clcsock_release_lock){+.+.}, at: [] smc_clcsock_accept net/smc/af_smc.c:600 [inline] #2: (&smc->clcsock_release_lock){+.+.}, at: [] smc_tcp_listen_work+0x6ac/0xb80 net/smc/af_smc.c:935 3 locks held by kworker/1:4/9226: #0: ("events"){+.+.}, at: [] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087 #1: ((&smc->tcp_listen_work)){+.+.}, at: [] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091 #2: (&smc->clcsock_release_lock){+.+.}, at: [] smc_clcsock_accept net/smc/af_smc.c:600 [inline] #2: (&smc->clcsock_release_lock){+.+.}, at: [] smc_tcp_listen_work+0x6ac/0xb80 net/smc/af_smc.c:935 1 lock held by syz-executor.4/25817: #0: (net_mutex){+.+.}, at: [] copy_net_ns+0x156/0x440 net/core/net_namespace.c:410 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1508 Comm: khungtaskd Not tainted 4.14.226-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x13a/0x180 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x5b9/0xb40 kernel/hung_task.c:274 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at pc 0xffffffff872134ae