IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_bridge: link becomes ready
IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready
IPv6: ADDRCONF(NETDEV_UP): veth1: link is not ready
IPv6: ADDRCONF(NETDEV_CHANGE): veth1: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready
INFO: task syz-executor0:9528 blocked for more than 140 seconds.
      Not tainted 4.9.116-g0137ea2 #18
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor0   D28360  9528   8030 0x00000004
 ffff880197b96000 ffff8801c9ff0540 ffff8801c9ff0540 ffff880197493000
 ffff8801db321c18 ffff88019776f4a8 ffffffff839ead0d dffffc0000000000
 ffff8801d6390530 ffff88019776f468 00ff880197b968c0 ffff8801db3224e8
Call Trace:
 [<ffffffff839ec30f>] schedule+0x7f/0x1b0 kernel/sched/core.c:3553
 [<ffffffff815c7ec2>] d_wait_lookup fs/dcache.c:2455 [inline]
 [<ffffffff815c7ec2>] d_alloc_parallel+0xeb2/0x17c0 fs/dcache.c:2537
 [<ffffffff81594e7c>] lookup_slow+0x19c/0x470 fs/namei.c:1650
 [<ffffffff815a14a6>] walk_component+0x716/0x1bb0 fs/namei.c:1784
 [<ffffffff815a31c9>] link_path_walk+0x889/0x1200 fs/namei.c:2120
 [<ffffffff815a423d>] path_openat+0x1ad/0x3590 fs/namei.c:3533
 [<ffffffff815ab8e7>] do_filp_open+0x197/0x270 fs/namei.c:3568
 [<ffffffff8156e0bd>] do_sys_open+0x30d/0x5c0 fs/open.c:1072
 [<ffffffff8156e3e0>] SYSC_openat fs/open.c:1099 [inline]
 [<ffffffff8156e3e0>] SyS_openat+0x30/0x40 fs/open.c:1093
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839fbc13>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb

Showing all locks held in the system:
2 locks held by khungtaskd/519:
 #0:  (rcu_read_lock){......}, at: [<ffffffff8136677c>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff8136677c>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff81425e07>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
2 locks held by rs:main Q:Reg/3664:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff815d835c>] __fdget_pos+0xac/0xd0 fs/file.c:781
 #1:  (sb_writers#3){.+.+.+}, at: [<ffffffff81572e3e>] file_start_write include/linux/fs.h:2640 [inline]
 #1:  (sb_writers#3){.+.+.+}, at: [<ffffffff81572e3e>] vfs_write+0x3ae/0x530 fs/read_write.c:556
2 locks held by getty/3762:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff839f9db2>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff82120212>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142
1 lock held by syz-executor0/9528:
 #0:  (&sb->s_type->i_mutex_key#16){++++++}, at: [<ffffffff81594e21>] inode_lock_shared include/linux/fs.h:776 [inline]
 #0:  (&sb->s_type->i_mutex_key#16){++++++}, at: [<ffffffff81594e21>] lookup_slow+0x141/0x470 fs/namei.c:1645

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

NMI backtrace for cpu 1
CPU: 1 PID: 519 Comm: khungtaskd Not tainted 4.9.116-g0137ea2 #18
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d86d7d08 ffffffff81eb46a9 0000000000000000 0000000000000001
 0000000000000001 0000000000000001 ffffffff810b9bd0 ffff8801d86d7d40
 ffffffff81ebf9a7 0000000000000001 0000000000000000 0000000000000003
Call Trace:
 [<ffffffff81eb46a9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb46a9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81ebf9a7>] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81ebf93a>] nmi_trigger_cpumask_backtrace+0x12a/0x14f lib/nmi_backtrace.c:60
 [<ffffffff810b9cd4>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff81366d14>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81366d14>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81366d14>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81366d14>] watchdog+0x6b4/0xa20 kernel/hung_task.c:239
 [<ffffffff8119d0ad>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff839fbddc>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 9516 Comm: syz-executor0 Not tainted 4.9.116-g0137ea2 #18
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff880198550000 task.stack: ffff8801c1fb0000
RIP: 0010:[<ffffffff8123abcd>] 
c [<ffffffff8123abcd>] arch_local_save_flags arch/x86/include/asm/paravirt.h:763 [inline]
RIP: 0010:[<ffffffff8123abcd>] 
c [<ffffffff8123abcd>] arch_local_irq_save arch/x86/include/asm/paravirt.h:785 [inline]
RIP: 0010:[<ffffffff8123abcd>] 
c [<ffffffff8123abcd>] lock_acquire+0x6d/0x3e0 kernel/locking/lockdep.c:3751
RSP: 0018:ffff8801c1fb6f68  EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff880198550000 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8801985508c4
RBP: ffff8801c1fb6fd8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff846defa0
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000002
FS:  00007f9a61946700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000022aa818 CR3: 00000001da224000 CR4: 00000000001606f0
DR0: ffffffffffffff00 DR1: 0000000020000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Stack:
 0000000000000246
c 0000000000000001
c dffffc0000000000
c 0000000000000000
c
 ffff8801d6145f88
c ffff8801c1fb6fe8
c ffffffff8143a1c1
c 0000000000000001
c
 00000000985508c8
c ffff8801d6145f88
c 0000000000000007
c dffffc0000000000
c
Call Trace:
 [<ffffffff81438caa>] rcu_lock_acquire include/linux/rcupdate.h:493 [inline]
 [<ffffffff81438caa>] rcu_read_lock include/linux/rcupdate.h:875 [inline]
 [<ffffffff81438caa>] find_get_entry+0x4a/0x540 mm/filemap.c:1090
 [<ffffffff8143a0db>] pagecache_get_page+0x4b/0x720 mm/filemap.c:1201
 [<ffffffff816255c9>] find_or_create_page include/linux/pagemap.h:309 [inline]
 [<ffffffff816255c9>] grow_dev_page fs/buffer.c:1005 [inline]
 [<ffffffff816255c9>] grow_buffers fs/buffer.c:1078 [inline]
 [<ffffffff816255c9>] __getblk_slow fs/buffer.c:1105 [inline]
 [<ffffffff816255c9>] __getblk_gfp+0x249/0x710 fs/buffer.c:1386
 [<ffffffff81628ead>] __bread_gfp+0x2d/0x270 fs/buffer.c:1420
 [<ffffffff818b7718>] sb_bread include/linux/buffer_head.h:300 [inline]
 [<ffffffff818b7718>] fat__get_entry+0x4c8/0x8f0 fs/fat/dir.c:100
 [<ffffffff818bf517>] fat_get_entry fs/fat/dir.c:128 [inline]
 [<ffffffff818bf517>] fat_search_long+0x277/0x1180 fs/fat/dir.c:477
 [<ffffffff818d9a84>] vfat_find+0x134/0x180 fs/fat/namei_vfat.c:708
 [<ffffffff818da261>] vfat_lookup+0xe1/0x530 fs/fat/namei_vfat.c:731
 [<ffffffff81594f1e>] lookup_slow+0x23e/0x470 fs/namei.c:1668
 [<ffffffff815a14a6>] walk_component+0x716/0x1bb0 fs/namei.c:1784
 [<ffffffff815a31c9>] link_path_walk+0x889/0x1200 fs/namei.c:2120
 [<ffffffff815a423d>] path_openat+0x1ad/0x3590 fs/namei.c:3533
 [<ffffffff815ab8e7>] do_filp_open+0x197/0x270 fs/namei.c:3568
 [<ffffffff8156e0bd>] do_sys_open+0x30d/0x5c0 fs/open.c:1072
 [<ffffffff8156e3e0>] SYSC_openat fs/open.c:1099 [inline]
 [<ffffffff8156e3e0>] SyS_openat+0x30/0x40 fs/open.c:1093
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839fbc13>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Code: 
cc1 
cea 
c03 
c0f 
cb6 
c14 
c02 
c48 
c89 
cf8 
c83 
ce0 
c07 
c83 
cc0 
c03 
c38 
cd0 
c7c 
c08 
c84 
cd2 
c0f 
c85 
cba 
c02 
c00 
c00 
c8b 
c83 
cc4 
c08 
c00 
c00 
c85 
cc0 
c0f 
c85 
c0c 
c01 
c00 
c00 
c9c 
c<58> 
c0f 
c1f 
c44 
c00 
c00 
c48 
c89 
cc3 
cfa 
c66 
c0f 
c1f 
c44 
c00 
c00 
c65 
c48 
c8b 
c14 
c25 
c