INFO: task syz-executor454:7556 blocked for more than 140 seconds. Not tainted 4.14.113 #3 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor454 D28848 7556 7105 0x00000004 Call Trace: context_switch kernel/sched/core.c:2807 [inline] __schedule+0x7be/0x1cf0 kernel/sched/core.c:3383 schedule+0x92/0x1c0 kernel/sched/core.c:3427 schedule_timeout+0x93d/0xe10 kernel/time/timer.c:1721 do_wait_for_common kernel/sched/completion.c:91 [inline] __wait_for_common kernel/sched/completion.c:112 [inline] wait_for_common kernel/sched/completion.c:123 [inline] wait_for_completion+0x27c/0x420 kernel/sched/completion.c:144 flush_work+0x3eb/0x730 kernel/workqueue.c:2885 __cancel_work_timer+0x2f0/0x480 kernel/workqueue.c:2956 cancel_work_sync+0x18/0x20 kernel/workqueue.c:2992 p9_conn_destroy net/9p/trans_fd.c:872 [inline] p9_fd_close+0x2a1/0x450 net/9p/trans_fd.c:899 p9_client_create+0x793/0x1130 net/9p/client.c:1095 v9fs_session_init+0x1dc/0x1630 fs/9p/v9fs.c:422 v9fs_mount+0x7d/0x870 fs/9p/vfs_super.c:135 mount_fs+0x9d/0x2a7 fs/super.c:1237 vfs_kern_mount.part.0+0x5e/0x3d0 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0x417/0x27d0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xab/0x120 fs/namespace.c:3072 do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x4469a9 RSP: 002b:00007f42d1314db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00000000006dbc48 RCX: 00000000004469a9 RDX: 0000000020000100 RSI: 00000000200000c0 RDI: 0000000000000000 RBP: 00000000006dbc40 R08: 0000000020000140 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc4c R13: 00007ffd4ac815bf R14: 00007f42d13159c0 R15: 0000000000000000 INFO: task syz-executor454:7614 blocked for more than 140 seconds. Not tainted 4.14.113 #3 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor454 D28848 7614 7106 0x00000004 Call Trace: context_switch kernel/sched/core.c:2807 [inline] __schedule+0x7be/0x1cf0 kernel/sched/core.c:3383 schedule+0x92/0x1c0 kernel/sched/core.c:3427 schedule_timeout+0x93d/0xe10 kernel/time/timer.c:1721 do_wait_for_common kernel/sched/completion.c:91 [inline] __wait_for_common kernel/sched/completion.c:112 [inline] wait_for_common kernel/sched/completion.c:123 [inline] wait_for_completion+0x27c/0x420 kernel/sched/completion.c:144 flush_work+0x3eb/0x730 kernel/workqueue.c:2885 __cancel_work_timer+0x2f0/0x480 kernel/workqueue.c:2956 cancel_work_sync+0x18/0x20 kernel/workqueue.c:2992 p9_conn_destroy net/9p/trans_fd.c:872 [inline] p9_fd_close+0x2a1/0x450 net/9p/trans_fd.c:899 p9_client_create+0x793/0x1130 net/9p/client.c:1095 v9fs_session_init+0x1dc/0x1630 fs/9p/v9fs.c:422 v9fs_mount+0x7d/0x870 fs/9p/vfs_super.c:135 mount_fs+0x9d/0x2a7 fs/super.c:1237 vfs_kern_mount.part.0+0x5e/0x3d0 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0x417/0x27d0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xab/0x120 fs/namespace.c:3072 do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x4469a9 RSP: 002b:00007f42d12d2db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00000000006dbc68 RCX: 00000000004469a9 RDX: 0000000020000100 RSI: 00000000200000c0 RDI: 0000000000000000 RBP: 00000000006dbc60 R08: 0000000020000140 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc6c R13: 00007ffd4ac815bf R14: 00007f42d12d39c0 R15: 0000000000000000 INFO: task syz-executor454:7606 blocked for more than 140 seconds. Not tainted 4.14.113 #3 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor454 D28848 7606 7103 0x00000004 Call Trace: context_switch kernel/sched/core.c:2807 [inline] __schedule+0x7be/0x1cf0 kernel/sched/core.c:3383 schedule+0x92/0x1c0 kernel/sched/core.c:3427 schedule_timeout+0x93d/0xe10 kernel/time/timer.c:1721 do_wait_for_common kernel/sched/completion.c:91 [inline] __wait_for_common kernel/sched/completion.c:112 [inline] wait_for_common kernel/sched/completion.c:123 [inline] wait_for_completion+0x27c/0x420 kernel/sched/completion.c:144 flush_work+0x3eb/0x730 kernel/workqueue.c:2885 __cancel_work_timer+0x2f0/0x480 kernel/workqueue.c:2956 cancel_work_sync+0x18/0x20 kernel/workqueue.c:2992 p9_conn_destroy net/9p/trans_fd.c:872 [inline] p9_fd_close+0x2a1/0x450 net/9p/trans_fd.c:899 p9_client_create+0x793/0x1130 net/9p/client.c:1095 v9fs_session_init+0x1dc/0x1630 fs/9p/v9fs.c:422 v9fs_mount+0x7d/0x870 fs/9p/vfs_super.c:135 mount_fs+0x9d/0x2a7 fs/super.c:1237 vfs_kern_mount.part.0+0x5e/0x3d0 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0x417/0x27d0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xab/0x120 fs/namespace.c:3072 do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x4469a9 RSP: 002b:00007f42d1314db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00000000006dbc48 RCX: 00000000004469a9 RDX: 0000000020000100 RSI: 00000000200000c0 RDI: 0000000000000000 RBP: 00000000006dbc40 R08: 0000000020000140 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc4c R13: 00007ffd4ac815bf R14: 00007f42d13159c0 R15: 0000000000000000 INFO: task syz-executor454:7612 blocked for more than 140 seconds. Not tainted 4.14.113 #3 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor454 D28848 7612 7104 0x00000004 Call Trace: context_switch kernel/sched/core.c:2807 [inline] __schedule+0x7be/0x1cf0 kernel/sched/core.c:3383 schedule+0x92/0x1c0 kernel/sched/core.c:3427 schedule_timeout+0x93d/0xe10 kernel/time/timer.c:1721 do_wait_for_common kernel/sched/completion.c:91 [inline] __wait_for_common kernel/sched/completion.c:112 [inline] wait_for_common kernel/sched/completion.c:123 [inline] wait_for_completion+0x27c/0x420 kernel/sched/completion.c:144 flush_work+0x3eb/0x730 kernel/workqueue.c:2885 __cancel_work_timer+0x2f0/0x480 kernel/workqueue.c:2956 cancel_work_sync+0x18/0x20 kernel/workqueue.c:2992 p9_conn_destroy net/9p/trans_fd.c:872 [inline] p9_fd_close+0x2a1/0x450 net/9p/trans_fd.c:899 p9_client_create+0x793/0x1130 net/9p/client.c:1095 v9fs_session_init+0x1dc/0x1630 fs/9p/v9fs.c:422 v9fs_mount+0x7d/0x870 fs/9p/vfs_super.c:135 mount_fs+0x9d/0x2a7 fs/super.c:1237 vfs_kern_mount.part.0+0x5e/0x3d0 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0x417/0x27d0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xab/0x120 fs/namespace.c:3072 do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x4469a9 RSP: 002b:00007f42d1314db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00000000006dbc48 RCX: 00000000004469a9 RDX: 0000000020000100 RSI: 00000000200000c0 RDI: 0000000000000000 RBP: 00000000006dbc40 R08: 0000000020000140 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc4c R13: 00007ffd4ac815bf R14: 00007f42d13159c0 R15: 0000000000000000 INFO: task syz-executor454:7616 blocked for more than 140 seconds. Not tainted 4.14.113 #3 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor454 D28976 7616 7102 0x00000004 Call Trace: context_switch kernel/sched/core.c:2807 [inline] __schedule+0x7be/0x1cf0 kernel/sched/core.c:3383 schedule+0x92/0x1c0 kernel/sched/core.c:3427 schedule_timeout+0x93d/0xe10 kernel/time/timer.c:1721 do_wait_for_common kernel/sched/completion.c:91 [inline] __wait_for_common kernel/sched/completion.c:112 [inline] wait_for_common kernel/sched/completion.c:123 [inline] wait_for_completion+0x27c/0x420 kernel/sched/completion.c:144 flush_work+0x3eb/0x730 kernel/workqueue.c:2885 __cancel_work_timer+0x2f0/0x480 kernel/workqueue.c:2956 cancel_work_sync+0x18/0x20 kernel/workqueue.c:2992 p9_conn_destroy net/9p/trans_fd.c:872 [inline] p9_fd_close+0x2a1/0x450 net/9p/trans_fd.c:899 p9_client_create+0x793/0x1130 net/9p/client.c:1095 v9fs_session_init+0x1dc/0x1630 fs/9p/v9fs.c:422 v9fs_mount+0x7d/0x870 fs/9p/vfs_super.c:135 mount_fs+0x9d/0x2a7 fs/super.c:1237 vfs_kern_mount.part.0+0x5e/0x3d0 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0x417/0x27d0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xab/0x120 fs/namespace.c:3072 do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x4469a9 RSP: 002b:00007f42d1314db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00000000006dbc48 RCX: 00000000004469a9 RDX: 0000000020000100 RSI: 00000000200000c0 RDI: 0000000000000000 RBP: 00000000006dbc40 R08: 0000000020000140 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc4c R13: 00007ffd4ac815bf R14: 00007f42d13159c0 R15: 0000000000000000 INFO: task syz-executor454:7621 blocked for more than 140 seconds. Not tainted 4.14.113 #3 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor454 D28848 7621 7101 0x00000004 Call Trace: context_switch kernel/sched/core.c:2807 [inline] __schedule+0x7be/0x1cf0 kernel/sched/core.c:3383 schedule+0x92/0x1c0 kernel/sched/core.c:3427 schedule_timeout+0x93d/0xe10 kernel/time/timer.c:1721 do_wait_for_common kernel/sched/completion.c:91 [inline] __wait_for_common kernel/sched/completion.c:112 [inline] wait_for_common kernel/sched/completion.c:123 [inline] wait_for_completion+0x27c/0x420 kernel/sched/completion.c:144 flush_work+0x3eb/0x730 kernel/workqueue.c:2885 __cancel_work_timer+0x2f0/0x480 kernel/workqueue.c:2956 cancel_work_sync+0x18/0x20 kernel/workqueue.c:2992 p9_conn_destroy net/9p/trans_fd.c:872 [inline] p9_fd_close+0x2a1/0x450 net/9p/trans_fd.c:899 p9_client_create+0x793/0x1130 net/9p/client.c:1095 v9fs_session_init+0x1dc/0x1630 fs/9p/v9fs.c:422 v9fs_mount+0x7d/0x870 fs/9p/vfs_super.c:135 mount_fs+0x9d/0x2a7 fs/super.c:1237 vfs_kern_mount.part.0+0x5e/0x3d0 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0x417/0x27d0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xab/0x120 fs/namespace.c:3072 do_syscall_64+0x1eb/0x630 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x4469a9 RSP: 002b:00007f42d1314db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00000000006dbc48 RCX: 00000000004469a9 RDX: 0000000020000100 RSI: 00000000200000c0 RDI: 0000000000000000 RBP: 00000000006dbc40 R08: 0000000020000140 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc4c R13: 00007ffd4ac815bf R14: 00007f42d13159c0 R15: 0000000000000000 Showing all locks held in the system: 2 locks held by kworker/0:1/944: #0: ("events"){+.+.}, at: [] work_static include/linux/workqueue.h:199 [inline] #0: ("events"){+.+.}, at: [] set_work_data kernel/workqueue.c:619 [inline] #0: ("events"){+.+.}, at: [] set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: ("events"){+.+.}, at: [] process_one_work+0x76e/0x1610 kernel/workqueue.c:2085 #1: ((&m->rq)){+.+.}, at: [] process_one_work+0x7ab/0x1610 kernel/workqueue.c:2089 1 lock held by khungtaskd/1008: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4544 2 locks held by kworker/1:2/2677: #0: ("events"){+.+.}, at: [] work_static include/linux/workqueue.h:199 [inline] #0: ("events"){+.+.}, at: [] set_work_data kernel/workqueue.c:619 [inline] #0: ("events"){+.+.}, at: [] set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: ("events"){+.+.}, at: [] process_one_work+0x76e/0x1610 kernel/workqueue.c:2085 #1: ((&m->rq)){+.+.}, at: [] process_one_work+0x7ab/0x1610 kernel/workqueue.c:2089 2 locks held by kworker/0:2/3144: #0: ("events"){+.+.}, at: [] work_static include/linux/workqueue.h:199 [inline] #0: ("events"){+.+.}, at: [] set_work_data kernel/workqueue.c:619 [inline] #0: ("events"){+.+.}, at: [] set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: ("events"){+.+.}, at: [] process_one_work+0x76e/0x1610 kernel/workqueue.c:2085 #1: ((&m->rq)){+.+.}, at: [] process_one_work+0x7ab/0x1610 kernel/workqueue.c:2089 1 lock held by rsyslogd/6949: #0: (&f->f_pos_lock){+.+.}, at: [] __fdget_pos+0xab/0xd0 fs/file.c:769 2 locks held by getty/7072: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/7073: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/7074: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/7075: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/7076: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/7077: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by getty/7078: #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156 2 locks held by kworker/0:0/7201: #0: ("events"){+.+.}, at: [] work_static include/linux/workqueue.h:199 [inline] #0: ("events"){+.+.}, at: [] set_work_data kernel/workqueue.c:619 [inline] #0: ("events"){+.+.}, at: [] set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: ("events"){+.+.}, at: [] process_one_work+0x76e/0x1610 kernel/workqueue.c:2085 #1: ((&m->rq)){+.+.}, at: [] process_one_work+0x7ab/0x1610 kernel/workqueue.c:2089 2 locks held by kworker/0:3/7202: #0: ("events"){+.+.}, at: [] work_static include/linux/workqueue.h:199 [inline] #0: ("events"){+.+.}, at: [] set_work_data kernel/workqueue.c:619 [inline] #0: ("events"){+.+.}, at: [] set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: ("events"){+.+.}, at: [] process_one_work+0x76e/0x1610 kernel/workqueue.c:2085 #1: ((&m->rq)){+.+.}, at: [] process_one_work+0x7ab/0x1610 kernel/workqueue.c:2089 2 locks held by kworker/0:4/7381: #0: ("events"){+.+.}, at: [] work_static include/linux/workqueue.h:199 [inline] #0: ("events"){+.+.}, at: [] set_work_data kernel/workqueue.c:619 [inline] #0: ("events"){+.+.}, at: [] set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: ("events"){+.+.}, at: [] process_one_work+0x76e/0x1610 kernel/workqueue.c:2085 #1: ((&m->rq)){+.+.}, at: [] process_one_work+0x7ab/0x1610 kernel/workqueue.c:2089 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1008 Comm: khungtaskd Not tainted 4.14.113 #3 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+0x138/0x19c lib/dump_stack.c:53 nmi_cpu_backtrace.cold+0x57/0x94 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x141/0x189 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x5e7/0xb90 kernel/hung_task.c:274 kthread+0x31c/0x430 kernel/kthread.c:232 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:402 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at pc 0xffffffff861b0e02