block nbd4: Device being setup by another task block nbd4: shutting down sockets block nbd5: shutting down sockets INFO: task syz-executor.4:30812 blocked for more than 140 seconds. Not tainted 4.19.102-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28024 30812 7757 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x866/0x1dc0 kernel/sched/core.c:3515 schedule+0x92/0x1c0 kernel/sched/core.c:3559 schedule_timeout+0x8c8/0xfc0 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 kernel/sched/completion.c:115 [inline] wait_for_completion+0x29c/0x440 kernel/sched/completion.c:136 flush_workqueue+0x40f/0x14b0 kernel/workqueue.c:2713 nbd_start_device_ioctl drivers/block/nbd.c:1252 [inline] __nbd_ioctl drivers/block/nbd.c:1323 [inline] nbd_ioctl+0x546/0xcc0 drivers/block/nbd.c:1363 __blkdev_driver_ioctl block/ioctl.c:303 [inline] blkdev_ioctl+0xc2c/0x1ab3 block/ioctl.c:601 block_ioctl+0xee/0x130 fs/block_dev.c:1894 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:688 ksys_ioctl+0xab/0xd0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:710 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45b3b9 Code: 0d bf ff ff eb bb cc cc cc cc cc cc cc cc cc cc cc 48 8b 44 24 08 84 00 48 83 c0 10 48 89 44 24 08 48 c7 44 24 10 00 00 00 00 <0f> 57 c0 0f 11 44 24 18 e9 3a 9a fc ff cc cc cc cc cc cc cc cc cc RSP: 002b:00007f8f04ddec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f8f04ddf6d4 RCX: 000000000045b3b9 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000003fd R14: 00000000004c5513 R15: 000000000075bf2c Showing all locks held in the system: 3 locks held by kworker/u4:0/7: 1 lock held by khungtaskd/1071: #0: 00000000ad8953d9 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:4438 2 locks held by kworker/u5:0/1216: #0: 00000000f43380b0 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline] #0: 00000000f43380b0 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 00000000f43380b0 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline] #0: 00000000f43380b0 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline] #0: 00000000f43380b0 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline] #0: 00000000f43380b0 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: 00000000f43380b0 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: process_one_work+0x87e/0x1750 kernel/workqueue.c:2124 #1: 00000000ce594ede ((work_completion)(&args->work)){+.+.}, at: process_one_work+0x8b4/0x1750 kernel/workqueue.c:2128 2 locks held by getty/8194: #0: 000000009424b64c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 0000000042b3e2e1 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/8195: #0: 000000006d840ad3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000003df3367e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/8196: #0: 00000000eb53afd1 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 0000000093093006 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/8197: #0: 00000000a3c378fd (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000c2ac8a7f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/8198: #0: 00000000e9fd5fe8 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000007efd6beb (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/8199: #0: 00000000d3a970a5 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000d3fa7268 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/8200: #0: 000000000612efc2 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 0000000027aebb31 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1071 Comm: khungtaskd Not tainted 4.19.102-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+0x63/0xa4 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b0/0x1f8 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:203 [inline] watchdog+0x9df/0xee0 kernel/hung_task.c:287 kthread+0x354/0x420 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 7 Comm: kworker/u4:0 Not tainted 4.19.102-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:kasan_check_write+0x0/0x20 mm/kasan/kasan.c:277 Code: 66 2e 0f 1f 84 00 00 00 00 00 55 89 f6 31 d2 48 89 e5 48 8b 4d 08 e8 5f fe ff ff 5d c3 0f 1f 00 66 2e 0f 1f 84 00 00 00 00 00 <55> 89 f6 ba 01 00 00 00 48 89 e5 48 8b 4d 08 e8 3c fe ff ff 5d c3 RSP: 0018:ffff8880aa35fa78 EFLAGS: 00000082 RAX: ffffffff8a7a7140 RBX: 0000000000000000 RCX: 1ffffffff11f269d RDX: dffffc0000000000 RSI: 0000000000000004 RDI: ffffffff8a7a7278 RBP: ffff8880aa35fc50 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000002 R13: 0000000000000000 R14: ffff8880aa34c1c0 R15: ffffffff88f934e0 FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 000000008ccdc000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x16f/0x3f0 kernel/locking/lockdep.c:3903 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+0x117/0x760 net/batman-adv/network-coding.c:730 process_one_work+0x989/0x1750 kernel/workqueue.c:2153 worker_thread+0x98/0xe40 kernel/workqueue.c:2296 kthread+0x354/0x420 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415