INFO: task syz-executor.1:22349 can't die for more than 143 seconds. syz-executor.1 D28048 22349 9825 0x00000004 Call Trace: context_switch kernel/sched/core.c:3380 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4080 schedule+0xdc/0x2b0 kernel/sched/core.c:4154 schedule_timeout+0x58d/0x8c0 kernel/time/timer.c:1874 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 rdma_destroy_id+0x680/0xdd0 drivers/infiniband/core/cma.c:1855 ucma_close+0x115/0x310 drivers/infiniband/core/ucma.c:1762 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x316/0x380 arch/x86/entry/common.c:165 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline] syscall_return_slowpath arch/x86/entry/common.c:279 [inline] do_syscall_64+0x676/0x790 arch/x86/entry/common.c:305 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x416011 Code: 49 89 fc 48 83 e7 0f 48 81 cf f0 00 00 00 49 8d 43 04 4c 39 d0 0f 83 ec 00 00 00 41 88 38 90 49 c1 ec 04 48 39 d6 74 5d 49 83 08 73 48 0f b6 02 48 89 cf 4c 89 c9 48 d3 e0 49 09 c4 90 48 8d RSP: 002b:00007fff5aa8bd50 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000416011 RDX: 0000001b31b20000 RSI: 0000000000000e94 RDI: 0000000000000003 RBP: 0000000000000001 R08: 000000009c372e94 R09: 000000009c372e98 R10: 00007fff5aa8be30 R11: 0000000000000293 R12: 000000000076c920 R13: 000000000076c920 R14: 000000000008f884 R15: 000000000076c1ac INFO: task syz-executor.1:22349 blocked for more than 143 seconds. Not tainted 5.6.0-rc3-next-20200225-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28048 22349 9825 0x00000004 Call Trace: context_switch kernel/sched/core.c:3380 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4080 schedule+0xdc/0x2b0 kernel/sched/core.c:4154 schedule_timeout+0x58d/0x8c0 kernel/time/timer.c:1874 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 rdma_destroy_id+0x680/0xdd0 drivers/infiniband/core/cma.c:1855 ucma_close+0x115/0x310 drivers/infiniband/core/ucma.c:1762 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x316/0x380 arch/x86/entry/common.c:165 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline] syscall_return_slowpath arch/x86/entry/common.c:279 [inline] do_syscall_64+0x676/0x790 arch/x86/entry/common.c:305 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x416011 Code: 49 89 fc 48 83 e7 0f 48 81 cf f0 00 00 00 49 8d 43 04 4c 39 d0 0f 83 ec 00 00 00 41 88 38 90 49 c1 ec 04 48 39 d6 74 5d 49 83 08 73 48 0f b6 02 48 89 cf 4c 89 c9 48 d3 e0 49 09 c4 90 48 8d RSP: 002b:00007fff5aa8bd50 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000416011 RDX: 0000001b31b20000 RSI: 0000000000000e94 RDI: 0000000000000003 RBP: 0000000000000001 R08: 000000009c372e94 R09: 000000009c372e98 R10: 00007fff5aa8be30 R11: 0000000000000293 R12: 000000000076c920 R13: 000000000076c920 R14: 000000000008f884 R15: 000000000076c1ac Showing all locks held in the system: 1 lock held by khungtaskd/1131: #0: ffffffff89badac0 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x279 kernel/locking/lockdep.c:5546 1 lock held by rsyslogd/9693: #0: ffff888095bdbb60 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:821 2 locks held by getty/9783: #0: ffff88809584e090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000182b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9784: #0: ffff88809c754090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000183b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9785: #0: ffff8880964cf090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000185b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9786: #0: ffff8880a9317090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000181b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9787: #0: ffff88809fdce090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900017cb2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9788: #0: ffff8880a9604090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000184b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9789: #0: ffff8880a75db090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000179b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1131 Comm: khungtaskd Not tainted 5.6.0-rc3-next-20200225-syzkaller #0 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+0x197/0x210 lib/dump_stack.c:118 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:147 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:249 [inline] watchdog+0xdf1/0x14e0 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: 72 Comm: kworker/u4:2 Not tainted 5.6.0-rc3-next-20200225-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:__lock_acquire+0x12/0x6320 kernel/locking/lockdep.c:4051 Code: 0e 5a 00 48 8b 75 d0 eb a5 0f 1f 44 00 00 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 41 57 45 89 cf 48 8d 85 78 ff ff ff 41 56 <49> 89 fe 41 55 48 c1 e8 03 41 89 d5 41 54 48 89 c7 53 48 81 ec 08 RSP: 0018:ffffc90001067c30 EFLAGS: 00000046 RAX: ffffc90001067bb8 RBX: 0000000000000000 RCX: 0000000000000002 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff89badac0 RBP: ffffc90001067c40 R08: 0000000000000000 R09: 0000000000000000 R10: fffffbfff154c0f8 R11: ffffffff8aa607c7 R12: ffffffff89badac0 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc662a89000 CR3: 00000000a071f000 CR4: 00000000001426f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4720 rcu_lock_acquire include/linux/rcupdate.h:208 [inline] rcu_read_lock include/linux/rcupdate.h:601 [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+0xa05/0x17a0 kernel/workqueue.c:2266 worker_thread+0x98/0xe40 kernel/workqueue.c:2412 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352