ldm_validate_partition_table(): Disk read failed. Dev nbd4: unable to read RDB block 0 nbd4: unable to read partition table NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 INFO: task syz-executor.4:1332 blocked for more than 140 seconds. Not tainted 4.19.107-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D26776 1332 8105 0x00000004 Call Trace: schedule+0x8d/0x1b0 kernel/sched/core.c:3559 schedule_timeout+0x896/0xf20 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+0x26a/0x3c0 kernel/sched/completion.c:136 flush_workqueue+0x40f/0x14b0 kernel/workqueue.c:2713 nbd_start_device_ioctl drivers/block/nbd.c:1262 [inline] __nbd_ioctl drivers/block/nbd.c:1333 [inline] nbd_ioctl+0x502/0xb80 drivers/block/nbd.c:1373 __blkdev_driver_ioctl block/ioctl.c:303 [inline] blkdev_ioctl+0xbf7/0x1a1c block/ioctl.c:601 block_ioctl+0xe9/0x130 fs/block_dev.c:1894 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcda/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: 0033:0x45c479 Code: Bad RIP value. RSP: 002b:00007f944f6a1c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f944f6a26d4 RCX: 000000000045c479 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003 RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000402 R14: 00000000004c65f9 R15: 000000000076bf2c Showing all locks held in the system: 1 lock held by khungtaskd/1078: #0: 0000000048ec61e6 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4436 2 locks held by login/8046: #0: 0000000093b25141 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000ceea702a (&tty->atomic_write_lock){+.+.}, at: tty_write_lock+0x1e/0x80 drivers/tty/tty_io.c:886 2 locks held by getty/8047: #0: 000000006c7e37bf (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000063b6801 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1a50 drivers/tty/n_tty.c:2154 2 locks held by getty/8048: #0: 00000000dbefeea2 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 0000000000b8ea3d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1a50 drivers/tty/n_tty.c:2154 2 locks held by getty/8049: #0: 00000000ab84e3e5 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000f1eb7365 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1a50 drivers/tty/n_tty.c:2154 2 locks held by getty/8050: #0: 000000008d92402a (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 000000003e305e85 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1a50 drivers/tty/n_tty.c:2154 2 locks held by getty/8051: #0: 0000000099b43434 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 000000004c9c0de5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1a50 drivers/tty/n_tty.c:2154 2 locks held by getty/8052: #0: 000000008fece799 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000104771c9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1a50 drivers/tty/n_tty.c:2154 2 locks held by kworker/u5:2/13338: #0: 00000000abe32fc5 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline] #0: 00000000abe32fc5 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 00000000abe32fc5 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline] #0: 00000000abe32fc5 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline] #0: 00000000abe32fc5 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline] #0: 00000000abe32fc5 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: 00000000abe32fc5 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: process_one_work+0x81a/0x1640 kernel/workqueue.c:2124 #1: 00000000d75527a2 ((work_completion)(&args->work)){+.+.}, at: process_one_work+0x84e/0x1640 kernel/workqueue.c:2128 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1078 Comm: khungtaskd Not tainted 4.19.107-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+0x188/0x20d 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+0x962/0xe40 kernel/hung_task.c:287 kthread+0x34a/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: 23 Comm: kworker/u4:1 Not tainted 4.19.107-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet RIP: 0010:__rcu_read_unlock+0x27/0x160 kernel/rcu/tree_plugin.h:421 Code: 0f 1f 00 48 b8 00 00 00 00 00 fc ff df 55 53 65 48 8b 1c 25 40 ee 01 00 48 8d ab 70 03 00 00 48 89 ea 48 c1 ea 03 0f b6 04 02 <84> c0 74 08 3c 03 0f 8e e5 00 00 00 8b 83 70 03 00 00 83 f8 01 74 RSP: 0018:ffff8880a9497bb8 EFLAGS: 00000a06 RAX: 0000000000000000 RBX: ffff8880a9486600 RCX: ffffffff870011b3 RDX: 1ffff11015290d2e RSI: ffffffff87000f4d RDI: 0000000000000001 RBP: ffff8880a9486970 R08: ffff8880a9486600 R09: ffffed1015cc4733 R10: ffffed1015cc4732 R11: ffff8880ae623993 R12: 0000000000000001 R13: 0000000000000001 R14: ffff8880872eeb40 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c43c9eb000 CR3: 000000008b84d000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_read_unlock include/linux/rcupdate.h:680 [inline] batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:952 [inline] batadv_iv_ogm_schedule_buff+0x7c5/0x11e0 net/batman-adv/bat_iv_ogm.c:1002 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:1046 [inline] batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:1039 [inline] batadv_iv_send_outstanding_bat_ogm_packet+0x5e0/0x7a0 net/batman-adv/bat_iv_ogm.c:1865 process_one_work+0x91f/0x1640 kernel/workqueue.c:2153 worker_thread+0x96/0xe20 kernel/workqueue.c:2296 kthread+0x34a/0x420 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415