NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 INFO: task syz-executor.5:18066 blocked for more than 140 seconds. Not tainted 4.19.130-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28568 18066 6932 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3515 schedule+0x8d/0x1b0 kernel/sched/core.c:3559 schedule_timeout+0x90e/0xef0 kernel/time/timer.c:1782 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common+0x29c/0x470 kernel/sched/completion.c:115 flush_workqueue+0x40b/0x13e0 kernel/workqueue.c:2715 nbd_start_device_ioctl drivers/block/nbd.c:1262 [inline] __nbd_ioctl drivers/block/nbd.c:1333 [inline] nbd_ioctl+0x759/0xbe0 drivers/block/nbd.c:1373 __blkdev_driver_ioctl block/ioctl.c:303 [inline] blkdev_ioctl+0x5cb/0x1a7e block/ioctl.c:601 block_ioctl+0xe9/0x130 fs/block_dev.c:1896 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45cb19 Code: Bad RIP value. RSP: 002b:00007fc1f78b9c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000004e9b80 RCX: 000000000045cb19 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000416 R14: 00000000004c6e52 R15: 00007fc1f78ba6d4 Showing all locks held in the system: 3 locks held by kworker/u4:3/121: #0: 0000000006ece174 (&rq->lock){-.-.}, at: idle_balance kernel/sched/fair.c:9688 [inline] #0: 0000000006ece174 (&rq->lock){-.-.}, at: pick_next_task_fair+0x556/0x1570 kernel/sched/fair.c:6840 #1: 00000000e0f4045e (rcu_read_lock){....}, at: cpu_of kernel/sched/sched.h:927 [inline] #1: 00000000e0f4045e (rcu_read_lock){....}, at: __update_idle_core+0x39/0x3e0 kernel/sched/fair.c:6057 #2: 00000000e0f4045e (rcu_read_lock){....}, at: batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:417 [inline] #2: 00000000e0f4045e (rcu_read_lock){....}, at: batadv_nc_worker+0xf3/0xd50 net/batman-adv/network-coding.c:730 1 lock held by khungtaskd/1079: #0: 00000000e0f4045e (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4440 1 lock held by in:imklog/6139: 2 locks held by kworker/u5:1/9561: #0: 000000004a2601b9 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2126 #1: 00000000877ef364 ((work_completion)(&args->work)){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2130 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1079 Comm: khungtaskd Not tainted 4.19.130-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+0x1fc/0x2fe lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1eb lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x991/0xe60 kernel/hung_task.c:287 kthread+0x30b/0x410 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 121 Comm: kworker/u4:3 Not tainted 4.19.130-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:rcu_read_unlock_sched_notrace include/linux/rcupdate.h:771 [inline] RIP: 0010:trace_lock_acquire include/trace/events/lock.h:13 [inline] RIP: 0010:lock_acquire+0x2fb/0x3c0 kernel/locking/lockdep.c:3906 Code: fe ff ff 65 ff 05 a5 5b b0 7e 48 8b 05 36 b0 55 08 e8 b9 e2 05 00 85 c0 74 09 80 3d 98 58 55 08 00 74 3f 65 ff 0d 85 5b b0 7e <0f> 85 3e fe ff ff e8 bb cc ae ff e9 34 fe ff ff 0f 0b 0f 0b 0f 0b RSP: 0018:ffff8880a97c7c58 EFLAGS: 00000086 RAX: 0000000000000000 RBX: ffff8880a96221c0 RCX: 0000000000000001 RDX: 0000000000000001 RSI: 0000000000000002 RDI: ffff8880a9622a44 RBP: ffffffff88d93820 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000004 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000002 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9e3542a008 CR3: 00000000a8d8b000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:242 [inline] rcu_read_lock include/linux/rcupdate.h:627 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:419 [inline] batadv_nc_worker+0x12d/0xd50 net/batman-adv/network-coding.c:730 process_one_work+0x864/0x1570 kernel/workqueue.c:2155 worker_thread+0x64c/0x1130 kernel/workqueue.c:2298 kthread+0x30b/0x410 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415