INFO: task syz-executor.1:3428 blocked for more than 143 seconds. Not tainted 5.4.0-rc4 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D26680 3428 9250 0x00004004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x94f/0x1e70 kernel/sched/core.c:4069 schedule+0xd9/0x260 kernel/sched/core.c:4136 schedule_timeout+0x717/0xc50 kernel/time/timer.c:1871 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/0x14c0 kernel/workqueue.c:2826 nbd_start_device_ioctl drivers/block/nbd.c:1272 [inline] __nbd_ioctl drivers/block/nbd.c:1347 [inline] nbd_ioctl+0xb2e/0xc44 drivers/block/nbd.c:1387 __blkdev_driver_ioctl block/ioctl.c:304 [inline] blkdev_ioctl+0xedb/0x1c20 block/ioctl.c:606 block_ioctl+0xee/0x130 fs/block_dev.c:1954 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0xdb6/0x13e0 fs/ioctl.c:696 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713 __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl fs/ioctl.c:718 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459cd9 Code: cc c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 48 8b 44 24 08 48 8d 5c 24 08 48 89 18 48 8b 1c 24 48 89 58 08 48 c7 40 20 <00> 00 00 00 48 89 68 30 48 8b 58 18 48 85 db 74 05 e8 d1 43 fd ff RSP: 002b:00007fda37f93c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000459cd9 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000006 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fda37f946d4 R13: 00000000004c3601 R14: 00000000004d7478 R15: 00000000ffffffff INFO: task syz-executor.1:3472 blocked for more than 143 seconds. Not tainted 5.4.0-rc4 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D24872 3472 9250 0x00004004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x94f/0x1e70 kernel/sched/core.c:4069 schedule+0xd9/0x260 kernel/sched/core.c:4136 io_schedule+0x1c/0x70 kernel/sched/core.c:5780 wait_on_page_bit_common mm/filemap.c:1175 [inline] wait_on_page_bit mm/filemap.c:1224 [inline] wait_on_page_locked include/linux/pagemap.h:527 [inline] wait_on_page_read mm/filemap.c:2768 [inline] do_read_cache_page+0xf2f/0x2140 mm/filemap.c:2811 read_cache_page+0x5e/0x70 mm/filemap.c:2895 read_mapping_page include/linux/pagemap.h:396 [inline] read_dev_sector+0x71/0x310 block/partition-generic.c:667 read_part_sector block/partitions/check.h:38 [inline] adfspart_check_ICS+0x12d/0xc90 block/partitions/acorn.c:361 check_partition+0x3bc/0x6ce block/partitions/check.c:167 rescan_partitions+0x230/0xa30 block/partition-generic.c:531 __blkdev_get+0x1213/0x1660 fs/block_dev.c:1637 blkdev_get+0x47/0x2c0 fs/block_dev.c:1707 blkdev_open+0x205/0x290 fs/block_dev.c:1846 do_dentry_open+0x4e6/0x1380 fs/open.c:797 vfs_open+0xa0/0xd0 fs/open.c:914 do_last fs/namei.c:3408 [inline] path_openat+0x10e9/0x46d0 fs/namei.c:3525 do_filp_open+0x1a1/0x280 fs/namei.c:3555 do_sys_open+0x3fe/0x5d0 fs/open.c:1097 __do_sys_open fs/open.c:1115 [inline] __se_sys_open fs/open.c:1110 [inline] __x64_sys_open+0x7e/0xc0 fs/open.c:1110 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413bc1 Code: 80 00 00 00 44 88 44 1c 30 48 c1 ee 07 48 ff c3 49 89 f0 49 81 f8 80 00 00 00 72 0b 48 83 fb 28 72 d8 e9 74 01 00 00 48 83 fb <28> 0f 83 63 01 00 00 44 88 44 1c 30 48 ff c3 48 ff c8 48 89 c6 eb RSP: 002b:00007fda37f727a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 6666666666666667 RCX: 0000000000413bc1 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007fda37f72850 RBP: 000000000075bfc8 R08: 000000000000000f R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00007fda37f736d4 R13: 00000000004c9419 R14: 00000000004e0b98 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1070: #0: ffffffff88fab040 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5337 1 lock held by rsyslogd/9082: #0: ffff888093e09d60 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/9204: #0: ffff8880a401f090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f512e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9205: #0: ffff8880a1859090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f492e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9206: #0: ffff8880a7f20090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f592e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9207: #0: ffff88809247c090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f5d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9208: #0: ffff888094629090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f552e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9209: #0: ffff88809e573090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f412e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9210: #0: ffff8880a0b8a090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f2d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by kworker/u5:1/10801: #0: ffff8880a4f8e528 ((wq_completion)knbd1-recv){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8880a4f8e528 ((wq_completion)knbd1-recv){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880a4f8e528 ((wq_completion)knbd1-recv){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8880a4f8e528 ((wq_completion)knbd1-recv){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8880a4f8e528 ((wq_completion)knbd1-recv){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: ffff8880a4f8e528 ((wq_completion)knbd1-recv){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: ffff8880a4f8e528 ((wq_completion)knbd1-recv){+.+.}, at: process_one_work+0x88b/0x1740 kernel/workqueue.c:2240 #1: ffff888055dc7dc0 ((work_completion)(&args->work)){+.+.}, at: process_one_work+0x8c1/0x1740 kernel/workqueue.c:2244 1 lock held by syz-executor.1/3472: #0: ffff8880808fd1b8 (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x19b/0x1660 fs/block_dev.c:1553 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1070 Comm: khungtaskd Not tainted 5.4.0-rc4 #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+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:205 [inline] watchdog+0x9d0/0xef0 kernel/hung_task.c:289 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 10899 Comm: kworker/u4:10 Not tainted 5.4.0-rc4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:756 [inline] RIP: 0010:lock_acquire+0x20b/0x410 kernel/locking/lockdep.c:4490 Code: 94 08 00 00 00 00 00 00 48 c1 e8 03 80 3c 10 00 0f 85 d3 01 00 00 48 83 3d 71 d1 99 07 00 0f 84 53 01 00 00 48 8b 7d c8 57 9d <0f> 1f 44 00 00 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 65 8b RSP: 0018:ffff888055aa7c80 EFLAGS: 00000286 RAX: 1ffffffff11e63d4 RBX: ffff88806b0e8180 RCX: ffffffff8158f240 RDX: dffffc0000000000 RSI: 0000000000000008 RDI: 0000000000000286 RBP: ffff888055aa7cc8 R08: 1ffffffff14efd34 R09: fffffbfff14efd35 R10: ffff88806b0e8a68 R11: ffff88806b0e8180 R12: ffffffff88fab040 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000002 FS: 0000000000000000(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000fe9000 CR3: 000000008fe86000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:208 [inline] rcu_read_lock include/linux/rcupdate.h:599 [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