IPv6: ADDRCONF(NETDEV_UP): hsr0: link is not ready
IPv6: ADDRCONF(NETDEV_CHANGE): hsr0: link becomes ready
BFS-fs: bfs_fill_super(): No BFS filesystem on loop4 (magic=00000000)
INFO: task syz-executor.2:15573 blocked for more than 140 seconds.
      Not tainted 4.14.258-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D30296 15573   8027 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2811 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3387
 schedule+0x8d/0x1b0 kernel/sched/core.c:3431
 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline]
 rwsem_down_read_failed+0x1e6/0x350 kernel/locking/rwsem-xadd.c:309
 call_rwsem_down_read_failed+0x14/0x30 arch/x86/lib/rwsem.S:94
 __down_read arch/x86/include/asm/rwsem.h:66 [inline]
 down_read+0x44/0x80 kernel/locking/rwsem.c:26
 __get_super.part.0+0x271/0x390 fs/super.c:678
 __get_super include/linux/spinlock.h:317 [inline]
 get_super+0x2b/0x50 fs/super.c:707
 fsync_bdev+0x14/0xc0 fs/block_dev.c:495
 blkdev_flushbuf block/ioctl.c:430 [inline]
 blkdev_ioctl+0x883/0x1830 block/ioctl.c:514
 block_ioctl+0xd9/0x120 fs/block_dev.c:1893
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7fcd69af0e99
RSP: 002b:00007fcd68445168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fcd69c04030 RCX: 00007fcd69af0e99
RDX: 0000000000000000 RSI: 0000000000001261 RDI: 0000000000000003
RBP: 00007fcd69b4aff1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff64d71f0f R14: 00007fcd68445300 R15: 0000000000022000

Showing all locks held in the system:
1 lock held by khungtaskd/1533:
 #0:  (tasklist_lock){.+.+}, at: [<ffffffff8701ebe7>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548
2 locks held by agetty/7943:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff8354f632>] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:284
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff835449b3>] n_tty_read+0x1e3/0x1680 drivers/tty/n_tty.c:2156
1 lock held by syz-executor.2/15573:
 #0:  (&type->s_umount_key#74){.+.+}, at: [<ffffffff81877471>] __get_super.part.0+0x271/0x390 fs/super.c:678

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 1533 Comm: khungtaskd Not tainted 4.14.258-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x13a/0x180 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline]
 watchdog+0x5b9/0xb40 kernel/hung_task.c:274
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 15565 Comm: syz-executor.2 Not tainted 4.14.258-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8880925f4100 task.stack: ffff8880597b8000
RIP: 0010:lookup_bh_lru fs/buffer.c:1324 [inline]
RIP: 0010:__find_get_block+0xe1/0xc40 fs/buffer.c:1353
RSP: 0018:ffff8880597bf740 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 000000000000000c RCX: ffffc90005fe0000
RDX: 0000000000040000 RSI: ffffffff8319d715 RDI: ffffffff87ccf280
RBP: 000000000000000c R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: ffff8880925f4100 R12: 0000000000000000
R13: dffffc0000000000 R14: 0000000000000138 R15: 0000000000000000
FS:  00007fcd68466700(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0914d78000 CR3: 00000000af859000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __getblk_slow+0x127/0x7a0 fs/buffer.c:1100
 __getblk_gfp fs/buffer.c:1383 [inline]
 __bread_gfp+0x206/0x2e0 fs/buffer.c:1428
 sb_bread include/linux/buffer_head.h:309 [inline]
 udf_tread+0xe1/0x130 fs/udf/misc.c:44
 udf_read_tagged+0x40/0x4c0 fs/udf/misc.c:219
 udf_check_anchor_block+0x18a/0x590 fs/udf/super.c:1823
 udf_scan_anchors+0x16d/0x530 fs/udf/super.c:1863
 udf_find_anchor fs/udf/super.c:1928 [inline]
 udf_load_vrs+0x775/0xa90 fs/udf/super.c:1985
 udf_fill_super+0x715/0x1660 fs/udf/super.c:2177
 mount_bdev+0x2b3/0x360 fs/super.c:1134
 mount_fs+0x92/0x2a0 fs/super.c:1237
 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046
 vfs_kern_mount fs/namespace.c:1036 [inline]
 do_new_mount fs/namespace.c:2572 [inline]
 do_mount+0xe65/0x2a10 fs/namespace.c:2902
 SYSC_mount fs/namespace.c:3118 [inline]
 SyS_mount+0xa8/0x120 fs/namespace.c:3095
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7fcd69af0e99
RSP: 002b:00007fcd68466168 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fcd69c03f60 RCX: 00007fcd69af0e99
RDX: 0000000020000040 RSI: 0000000020000280 RDI: 00000000200004c0
RBP: 00007fcd69b4aff1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff64d71f0f R14: 00007fcd68466300 R15: 0000000000022000
Code: 83 c3 01 83 fb 10 0f 84 02 01 00 00 e8 99 55 c2 ff 48 c7 c7 c0 83 93 87 89 dd e8 7b f3 86 01 65 4c 8b 3c ed a0 1c 03 00 4d 85 ff <4d> 89 fc 74 cb e8 75 55 c2 ff 49 8d 7f 18 48 89 fa 48 c1 ea 03 
----------------
Code disassembly (best guess):
   0:	83 c3 01             	add    $0x1,%ebx
   3:	83 fb 10             	cmp    $0x10,%ebx
   6:	0f 84 02 01 00 00    	je     0x10e
   c:	e8 99 55 c2 ff       	callq  0xffc255aa
  11:	48 c7 c7 c0 83 93 87 	mov    $0xffffffff879383c0,%rdi
  18:	89 dd                	mov    %ebx,%ebp
  1a:	e8 7b f3 86 01       	callq  0x186f39a
  1f:	65 4c 8b 3c ed a0 1c 	mov    %gs:0x31ca0(,%rbp,8),%r15
  26:	03 00
  28:	4d 85 ff             	test   %r15,%r15
* 2b:	4d 89 fc             	mov    %r15,%r12 <-- trapping instruction
  2e:	74 cb                	je     0xfffffffb
  30:	e8 75 55 c2 ff       	callq  0xffc255aa
  35:	49 8d 7f 18          	lea    0x18(%r15),%rdi
  39:	48 89 fa             	mov    %rdi,%rdx
  3c:	48 c1 ea 03          	shr    $0x3,%rdx