INFO: task syz-executor.2:17067 blocked for more than 140 seconds. Not tainted 5.0.0-rc8+ #2 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D29136 17067 15612 0x00000004 Call Trace: context_switch kernel/sched/core.c:2844 [inline] __schedule+0x817/0x1cc0 kernel/sched/core.c:3485 schedule+0x92/0x180 kernel/sched/core.c:3529 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:584 [inline] rwsem_down_write_failed+0x774/0xc30 kernel/locking/rwsem-xadd.c:613 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117 __down_write arch/x86/include/asm/rwsem.h:142 [inline] down_write+0x53/0x90 kernel/locking/rwsem.c:72 grab_super+0xaf/0x2c0 fs/super.c:384 sget_userns+0x35a/0xd30 fs/super.c:512 sget+0x10c/0x150 fs/super.c:571 mount_bdev+0xff/0x3c0 fs/super.c:1132 udf_mount+0x35/0x40 fs/udf/super.c:131 mount_fs+0x106/0x3ff fs/super.c:1258 vfs_kern_mount.part.0+0x6f/0x410 fs/namespace.c:959 vfs_kern_mount fs/namespace.c:949 [inline] do_new_mount fs/namespace.c:2513 [inline] do_mount+0x581/0x2d30 fs/namespace.c:2845 ksys_mount+0xdb/0x150 fs/namespace.c:3061 __do_sys_mount fs/namespace.c:3075 [inline] __se_sys_mount fs/namespace.c:3072 [inline] __x64_sys_mount+0xbe/0x150 fs/namespace.c:3072 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457e29 Code: Bad RIP value. RSP: 002b:00007f5cbb693c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000457e29 RDX: 0000000020000100 RSI: 00000000200000c0 RDI: 0000000020000040 RBP: 000000000073bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5cbb6946d4 R13: 00000000004c3bf7 R14: 00000000004d6e00 R15: 00000000ffffffff Showing all locks held in the system: 2 locks held by kworker/u4:2/30: #0: 000000004cced8c1 (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1149 [inline] #0: 000000004cced8c1 (&rq->lock){-.-.}, at: __schedule+0x1fc/0x1cc0 kernel/sched/core.c:3423 #1: 000000002d48f7e5 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}, at: process_one_work+0x8b4/0x1790 kernel/workqueue.c:2148 1 lock held by khungtaskd/1039: #0: 00000000075674fb (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:4389 1 lock held by udevd/3867: 1 lock held by rsyslogd/7904: #0: 00000000cbc4b3ad (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:795 2 locks held by getty/8025: #0: 0000000014aaa0e4 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000008a78598b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/8026: #0: 000000002554ddc3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000009650d84c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/8027: #0: 00000000edca6e6b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000008073eabe (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/8028: #0: 00000000bbe791d6 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000066b99389 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/8029: #0: 000000002b7c0f61 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000006507ca (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/8030: #0: 0000000090d3e872 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000001a7a952f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/8031: #0: 00000000242d5ac0 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000fa5d8a6d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 1 lock held by syz-executor.2/17032: 2 locks held by syz-executor.2/17067: #0: 000000005db0c55d (&bdev->bd_fsfreeze_mutex){+.+.}, at: mount_bdev+0x93/0x3c0 fs/super.c:1126 #1: 00000000fc94f8c4 (&type->s_umount_key#81){+.+.}, at: grab_super+0xaf/0x2c0 fs/super.c:384 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1039 Comm: khungtaskd Not tainted 5.0.0-rc8+ #2 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+0x63/0xa4 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1be/0x236 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+0x357/0x430 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 30 Comm: kworker/u4:2 Not tainted 5.0.0-rc8+ #2 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:mark_lock+0xac/0x1380 kernel/locking/lockdep.c:3036 Code: c1 e3 06 48 81 eb 40 01 00 00 48 81 c3 80 28 09 8a 48 8d 7b 30 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 a3 0e 00 00 4c 85 6b 30 0f 84 c1 00 00 00 41 bd 01 00 00 00 RSP: 0018:ffff8880a9897b20 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: ffffffff8a100b00 RCX: 1ffff11015310929 RDX: 1ffffffff1420166 RSI: ffff8880a9884928 RDI: ffffffff8a100b30 RBP: ffff8880a9897b68 R08: ffff8880a9884080 R09: ffff8880a9884948 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880a9884928 R13: 0000000000000004 R14: 0000000000000002 R15: ffff8880a9884080 FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000457dff CR3: 0000000040ece000 CR4: 00000000001426f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: mark_held_locks+0xb1/0x100 kernel/locking/lockdep.c:2740 __trace_hardirqs_on_caller kernel/locking/lockdep.c:2761 [inline] lockdep_hardirqs_on+0x19b/0x5d0 kernel/locking/lockdep.c:2814 trace_hardirqs_on+0x67/0x230 kernel/trace/trace_preemptirq.c:30 __local_bh_enable_ip+0x15a/0x270 kernel/softirq.c:194 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:176 [inline] _raw_spin_unlock_bh+0x31/0x40 kernel/locking/spinlock.c:200 spin_unlock_bh include/linux/spinlock.h:374 [inline] batadv_nc_purge_paths+0x267/0x370 net/batman-adv/network-coding.c:482 batadv_nc_worker+0x29c/0x760 net/batman-adv/network-coding.c:731 process_one_work+0x98e/0x1790 kernel/workqueue.c:2173 worker_thread+0x98/0xe40 kernel/workqueue.c:2319 kthread+0x357/0x430 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352