syzbot

binder: undelivered TRANSACTION_COMPLETE
binder: send failed reply for transaction 127, target dead
INFO: task syz-executor5:18611 blocked for more than 140 seconds.
      Not tainted 4.9.111-g03c70fe #58
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor5   D28928 18611   3857 0x00000004
 ffff8801d8cf9800 ffff8801d05f8fc0 ffff8801a5621a40 ffff8801952e3000
 ffff8801db221c18 ffff8801960f7970 ffffffff839e7ded 0000000041b58ab3
 ffffffff843c3108 ffffffff81236170 00ffe8ffffc01480 ffff8801db2224e8
Call Trace:
 [<ffffffff839e93ef>] schedule+0x7f/0x1b0 kernel/sched/core.c:3557
 [<ffffffff839f5801>] schedule_timeout+0x861/0xf70 kernel/time/timer.c:1768
 [<ffffffff839e75ca>] io_schedule_timeout+0x1ba/0x390 kernel/sched/core.c:5180
 [<ffffffff839ea839>] io_schedule include/linux/sched.h:460 [inline]
 [<ffffffff839ea839>] bit_wait_io+0x19/0xa0 kernel/sched/wait.c:582
 [<ffffffff839e9f83>] __wait_on_bit+0x93/0x120 kernel/sched/wait.c:383
 [<ffffffff81433f50>] wait_on_page_bit+0x130/0x140 mm/filemap.c:802
 [<ffffffff81434121>] wait_on_page_writeback include/linux/pagemap.h:526 [inline]
 [<ffffffff81434121>] __filemap_fdatawait_range+0x1c1/0x290 mm/filemap.c:453
 [<ffffffff81434215>] filemap_fdatawait_range+0x25/0x50 mm/filemap.c:483
 [<ffffffff8143cf65>] filemap_write_and_wait_range+0x85/0xb0 mm/filemap.c:584
 [<ffffffff8162f146>] blkdev_fsync+0x66/0xb0 fs/block_dev.c:369
 [<ffffffff8161a76c>] vfs_fsync_range+0x10c/0x260 fs/sync.c:195
 [<ffffffff8161a932>] vfs_fsync fs/sync.c:209 [inline]
 [<ffffffff8161a932>] do_fsync+0x42/0xb0 fs/sync.c:219
 [<ffffffff8161b0d9>] SYSC_fdatasync fs/sync.c:233 [inline]
 [<ffffffff8161b0d9>] SyS_fdatasync+0x19/0x20 fs/sync.c:231
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839f8cd3>] 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: [<ffffffff813666fc>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff813666fc>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff81425d87>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
1 lock held by rsyslogd/3676:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff815d810c>] __fdget_pos+0xac/0xd0 fs/file.c:781
2 locks held by getty/3772:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff839f6e92>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff8211e602>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2133

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

NMI backtrace for cpu 1
CPU: 1 PID: 519 Comm: khungtaskd Not tainted 4.9.111-g03c70fe #58
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d96dfd08 ffffffff81eb2729 0000000000000000 0000000000000001
 0000000000000001 0000000000000001 ffffffff810b9af0 ffff8801d96dfd40
 ffffffff81ebda27 0000000000000001 0000000000000000 0000000000000003
Call Trace:
 [<ffffffff81eb2729>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb2729>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81ebda27>] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81ebd9ba>] nmi_trigger_cpumask_backtrace+0x12a/0x14f lib/nmi_backtrace.c:60
 [<ffffffff810b9bf4>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff81366c94>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81366c94>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81366c94>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81366c94>] watchdog+0x6b4/0xa20 kernel/hung_task.c:239
 [<ffffffff8119d05d>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff839f8e9c>] 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 skipped: idling at pc 0xffffffff839f78f6