INFO: task syz-executor.5:7936 can't die for more than 143 seconds. syz-executor.5 D28168 7936 9324 0x00004004 Call Trace: context_switch /kernel/sched/core.c:3254 [inline] __schedule+0x755/0x1580 /kernel/sched/core.c:3880 schedule+0xa8/0x270 /kernel/sched/core.c:3944 schedule_timeout+0x717/0xc50 /kernel/time/timer.c:1783 do_wait_for_common /kernel/sched/completion.c:83 [inline] __wait_for_common /kernel/sched/completion.c:104 [inline] wait_for_common /kernel/sched/completion.c:115 [inline] wait_for_completion+0x29c/0x440 /kernel/sched/completion.c:136 __flush_work+0x508/0xa50 /kernel/workqueue.c:3040 __cancel_work_timer+0x3d9/0x540 /kernel/workqueue.c:3127 cancel_work_sync+0x18/0x20 /kernel/workqueue.c:3163 p9_conn_destroy /net/9p/trans_fd.c:868 [inline] p9_fd_close+0x329/0x570 /net/9p/trans_fd.c:898 p9_client_destroy+0xc9/0x360 /net/9p/client.c:1085 v9fs_session_init+0x102e/0x18c0 /fs/9p/v9fs.c:482 v9fs_mount+0x7d/0x920 /fs/9p/vfs_super.c:120 legacy_get_tree+0x113/0x220 /fs/fs_context.c:651 vfs_get_tree+0x8f/0x380 /fs/super.c:1483 do_new_mount /fs/namespace.c:2791 [inline] do_mount+0x13b3/0x1c30 /fs/namespace.c:3111 ksys_mount+0xdb/0x150 /fs/namespace.c:3320 __do_sys_mount /fs/namespace.c:3334 [inline] __se_sys_mount /fs/namespace.c:3331 [inline] __x64_sys_mount+0xbe/0x150 /fs/namespace.c:3331 do_syscall_64+0xfd/0x6a0 /arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459819 Code: 9b 00 00 00 48 83 ec 68 48 89 6c 24 60 48 8d 6c 24 60 48 8b 42 08 48 8b 4a 10 48 8b 5a 18 48 8b 72 20 48 8b 7a 28 48 8b 3f 4c <8b> 42 30 48 8b 52 38 48 85 d2 76 62 48 89 44 24 58 4c 89 44 24 28 RSP: 002b:00007fa8dfca0c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000459819 RDX: 0000000020000100 RSI: 0000000020000040 RDI: 0000000000000000 RBP: 000000000075c070 R08: 0000000020000280 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa8dfca16d4 R13: 00000000004c5c6d R14: 00000000004da4c8 R15: 00000000ffffffff INFO: task syz-executor.5:7936 blocked for more than 143 seconds. Not tainted 5.2.0-next-20190718 #41 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28168 7936 9324 0x00004004 Call Trace: context_switch /kernel/sched/core.c:3254 [inline] __schedule+0x755/0x1580 /kernel/sched/core.c:3880 schedule+0xa8/0x270 /kernel/sched/core.c:3944 schedule_timeout+0x717/0xc50 /kernel/time/timer.c:1783 do_wait_for_common /kernel/sched/completion.c:83 [inline] __wait_for_common /kernel/sched/completion.c:104 [inline] wait_for_common /kernel/sched/completion.c:115 [inline] wait_for_completion+0x29c/0x440 /kernel/sched/completion.c:136 __flush_work+0x508/0xa50 /kernel/workqueue.c:3040 __cancel_work_timer+0x3d9/0x540 /kernel/workqueue.c:3127 cancel_work_sync+0x18/0x20 /kernel/workqueue.c:3163 p9_conn_destroy /net/9p/trans_fd.c:868 [inline] p9_fd_close+0x329/0x570 /net/9p/trans_fd.c:898 p9_client_destroy+0xc9/0x360 /net/9p/client.c:1085 v9fs_session_init+0x102e/0x18c0 /fs/9p/v9fs.c:482 v9fs_mount+0x7d/0x920 /fs/9p/vfs_super.c:120 legacy_get_tree+0x113/0x220 /fs/fs_context.c:651 vfs_get_tree+0x8f/0x380 /fs/super.c:1483 do_new_mount /fs/namespace.c:2791 [inline] do_mount+0x13b3/0x1c30 /fs/namespace.c:3111 ksys_mount+0xdb/0x150 /fs/namespace.c:3320 __do_sys_mount /fs/namespace.c:3334 [inline] __se_sys_mount /fs/namespace.c:3331 [inline] __x64_sys_mount+0xbe/0x150 /fs/namespace.c:3331 do_syscall_64+0xfd/0x6a0 /arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459819 Code: 9b 00 00 00 48 83 ec 68 48 89 6c 24 60 48 8d 6c 24 60 48 8b 42 08 48 8b 4a 10 48 8b 5a 18 48 8b 72 20 48 8b 7a 28 48 8b 3f 4c <8b> 42 30 48 8b 52 38 48 85 d2 76 62 48 89 44 24 58 4c 89 44 24 28 RSP: 002b:00007fa8dfca0c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000459819 RDX: 0000000020000100 RSI: 0000000020000040 RDI: 0000000000000000 RBP: 000000000075c070 R08: 0000000020000280 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa8dfca16d4 R13: 00000000004c5c6d R14: 00000000004da4c8 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1054: #0: 000000004cedf1fb (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e /kernel/locking/lockdep.c:5257 3 locks held by rsyslogd/9174: #0: 00000000acc207ff (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 /fs/file.c:801 #1: 000000006dc0308d (&rq->lock){-.-.}, at: rq_lock /kernel/sched/sched.h:1207 [inline] #1: 000000006dc0308d (&rq->lock){-.-.}, at: __schedule+0x1f5/0x1580 /kernel/sched/core.c:3832 #2: 000000004cedf1fb (rcu_read_lock){....}, at: trace_sched_stat_runtime /./include/trace/events/sched.h:435 [inline] #2: 000000004cedf1fb (rcu_read_lock){....}, at: update_curr+0x2e8/0x8d0 /kernel/sched/fair.c:861 2 locks held by getty/9264: #0: 000000005cb49e22 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 /drivers/tty/tty_ldsem.c:341 #1: 000000003827ebbb (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 /drivers/tty/n_tty.c:2156 2 locks held by getty/9265: #0: 00000000fcc5fff7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 /drivers/tty/tty_ldsem.c:341 #1: 000000007a77b59c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 /drivers/tty/n_tty.c:2156 2 locks held by getty/9266: #0: 00000000f3406c19 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 /drivers/tty/tty_ldsem.c:341 #1: 0000000039652914 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 /drivers/tty/n_tty.c:2156 2 locks held by getty/9267: #0: 00000000b8f897a3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 /drivers/tty/tty_ldsem.c:341 #1: 000000004565d292 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 /drivers/tty/n_tty.c:2156 2 locks held by getty/9268: #0: 0000000098bfdefc (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 /drivers/tty/tty_ldsem.c:341 #1: 000000004c0a10f9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 /drivers/tty/n_tty.c:2156 2 locks held by getty/9269: #0: 00000000dbbec2ac (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 /drivers/tty/tty_ldsem.c:341 #1: 0000000019d43a19 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 /drivers/tty/n_tty.c:2156 2 locks held by getty/9270: #0: 00000000787b955b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 /drivers/tty/tty_ldsem.c:341 #1: 00000000c0f81c34 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 /drivers/tty/n_tty.c:2156 2 locks held by kworker/0:6/11481: #0: 00000000e6931216 ((wq_completion)events){+.+.}, at: __write_once_size /./include/linux/compiler.h:226 [inline] #0: 00000000e6931216 ((wq_completion)events){+.+.}, at: arch_atomic64_set /./arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 00000000e6931216 ((wq_completion)events){+.+.}, at: atomic64_set /./include/asm-generic/atomic-instrumented.h:855 [inline] #0: 00000000e6931216 ((wq_completion)events){+.+.}, at: atomic_long_set /./include/asm-generic/atomic-long.h:40 [inline] #0: 00000000e6931216 ((wq_completion)events){+.+.}, at: set_work_data /kernel/workqueue.c:620 [inline] #0: 00000000e6931216 ((wq_completion)events){+.+.}, at: set_work_pool_and_clear_pending /kernel/workqueue.c:647 [inline] #0: 00000000e6931216 ((wq_completion)events){+.+.}, at: process_one_work+0x88b/0x1740 /kernel/workqueue.c:2240 #1: 00000000770321b6 ((work_completion)(&m->wq)){+.+.}, at: process_one_work+0x8c1/0x1740 /kernel/workqueue.c:2244 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1054 Comm: khungtaskd Not tainted 5.2.0-next-20190718 #41 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack /lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 /lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x70/0xb2 /lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x23b/0x28b /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:146 [inline] check_hung_uninterruptible_tasks /kernel/hung_task.c:249 [inline] watchdog+0xc54/0x1320 /kernel/hung_task.c:333 kthread+0x361/0x430 /kernel/kthread.c:255 ret_from_fork+0x24/0x30 /arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 29719 Comm: kworker/u4:4 Not tainted 5.2.0-next-20190718 #41 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:separate_irq_context /kernel/locking/lockdep.c:3539 [inline] RIP: 0010:__lock_acquire+0x63d/0x4c30 /kernel/locking/lockdep.c:3864 Code: 00 fc ff df 48 c1 ea 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e 6c 35 00 00 41 8b 83 90 08 00 00 85 c0 74 77 48 8b b5 60 ff ff ff <48> 8d 04 80 4c 8d 74 c6 d8 48 b8 00 00 00 00 00 fc ff df 49 8d 7e RSP: 0018:ffff888057557b38 EFLAGS: 00000002 RAX: 0000000000000002 RBX: 0000000000000000 RCX: ffffffff81588694 RDX: 1ffff110133651c2 RSI: ffff888099b28e18 RDI: 0000000000000002 RBP: ffff888057557c50 R08: 1ffffffff14a7d40 R09: fffffbfff14a7d41 R10: ffff888099b28e68 R11: ffff888099b28580 R12: 0000000000000029 R13: a7b91d2781928fa6 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 000000009129e000 CR4: 00000000001406f0 Call Trace: lock_acquire+0x190/0x410 /kernel/locking/lockdep.c:4413 rcu_lock_acquire /./include/linux/rcupdate.h:208 [inline] rcu_read_lock /./include/linux/rcupdate.h:592 [inline] batadv_nc_purge_orig_hash /net/batman-adv/network-coding.c:407 [inline] batadv_nc_worker+0x117/0x760 /net/batman-adv/network-coding.c:718 process_one_work+0x9af/0x1740 /kernel/workqueue.c:2269 worker_thread+0x98/0xe40 /kernel/workqueue.c:2415 kthread+0x361/0x430 /kernel/kthread.c:255 ret_from_fork+0x24/0x30 /arch/x86/entry/entry_64.S:352