syzbot

SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=14899 comm=syz-executor1
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=14902 comm=syz-executor1
INFO: task syz-executor3:14890 blocked for more than 120 seconds.
      Not tainted 4.9.94-g8683408 #3
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor3   D27976 14890   3780 0x00000004
 ffff8801d3f21800 ffff8801d3831500 ffff8801be6cb9c0 ffff8801d79e9800
 ffff8801db321b98 ffff8801cdd37170 ffffffff838c040d 0000000041b58ab3
 ffffffff841a49d8 ffffffff81234350 0000000000000000 ffff8801db322468
Call Trace:
 [<ffffffff838c1a0f>] schedule+0x7f/0x1b0 kernel/sched/core.c:3557
 [<ffffffff838cde21>] schedule_timeout+0x861/0xf70 kernel/time/timer.c:1768
 [<ffffffff838bfbea>] io_schedule_timeout+0x1ba/0x390 kernel/sched/core.c:5180
 [<ffffffff838c2e59>] io_schedule include/linux/sched.h:460 [inline]
 [<ffffffff838c2e59>] bit_wait_io+0x19/0xa0 kernel/sched/wait.c:582
 [<ffffffff838c26fe>] __wait_on_bit_lock+0xce/0x1c0 kernel/sched/wait.c:421
 [<ffffffff8143240f>] __lock_page+0xff/0x160 mm/filemap.c:934
 [<ffffffff814682db>] lock_page include/linux/pagemap.h:454 [inline]
 [<ffffffff814682db>] invalidate_inode_pages2_range+0x41b/0xa10 mm/truncate.c:614
 [<ffffffff8143b19a>] generic_file_direct_write+0x3fa/0x510 mm/filemap.c:2629
 [<ffffffff8143b4cf>] __generic_file_write_iter+0x21f/0x540 mm/filemap.c:2823
 [<ffffffff81630cf7>] blkdev_write_iter+0x1b7/0x370 fs/block_dev.c:1718
 [<ffffffff8156dea0>] vfs_iter_write+0x2e0/0x460 fs/read_write.c:390
 [<ffffffff81614d2b>] iter_file_splice_write+0x5fb/0xb30 fs/splice.c:768
 [<ffffffff8160fd98>] do_splice_from fs/splice.c:870 [inline]
 [<ffffffff8160fd98>] direct_splice_actor+0x128/0x190 fs/splice.c:1037
 [<ffffffff816110e1>] splice_direct_to_actor+0x2c1/0x7e0 fs/splice.c:992
 [<ffffffff816117a3>] do_splice_direct+0x1a3/0x270 fs/splice.c:1080
 [<ffffffff81572d70>] do_sendfile+0x4f0/0xc60 fs/read_write.c:1393
 [<ffffffff81574df1>] SYSC_sendfile64 fs/read_write.c:1448 [inline]
 [<ffffffff81574df1>] SyS_sendfile64+0xd1/0x160 fs/read_write.c:1440
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff838d1313>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb

Showing all locks held in the system:
2 locks held by khungtaskd/515:
 #0:  (rcu_read_lock){......}, at: [<ffffffff813646bc>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff813646bc>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff81423bb0>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
1 lock held by rsyslogd/3590:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff815d565c>] __fdget_pos+0xac/0xd0 fs/file.c:781
2 locks held by getty/3686:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff838cf4b2>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+.+.}, at: [<ffffffff82007082>] n_tty_read+0x202/0x16b0 drivers/tty/n_tty.c:2133
1 lock held by blkid/12568:
 #0:  (&bdev->bd_mutex){+.+.+.}, at: [<ffffffff8162e06b>] __blkdev_put+0xbb/0x840 fs/block_dev.c:1579

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

NMI backtrace for cpu 0
CPU: 0 PID: 515 Comm: khungtaskd Not tainted 4.9.94-g8683408 #3
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d87bfd08 ffffffff81d9b509 0000000000000000 0000000000000000
 0000000000000000 0000000000000001 ffffffff810b7d60 ffff8801d87bfd40
 ffffffff81da6837 0000000000000000 0000000000000000 0000000000000002
Call Trace:
 [<ffffffff81d9b509>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d9b509>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81da6837>] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81da67ca>] nmi_trigger_cpumask_backtrace+0x12a/0x14f lib/nmi_backtrace.c:60
 [<ffffffff810b7e64>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff81364c54>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81364c54>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81364c54>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81364c54>] watchdog+0x6b4/0xa20 kernel/hung_task.c:239
 [<ffffffff8119ad2d>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff838d14dc>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at pc 0xffffffff838cff16