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INFO: task hung in generic_file_direct_write

Status: auto-closed as invalid on 2019/02/22 14:09
First crash: 2222d, last: 2189d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-44 INFO: task hung in generic_file_direct_write 1 2201d 2201d 0/2 auto-closed as invalid on 2019/02/22 12:38
upstream INFO: task hung in generic_file_direct_write fs mm 1 248d 248d 0/26 auto-obsoleted due to no activity on 2023/11/07 07:29

Sample crash report:
Buffer I/O error on dev loop0, logical block 3, async page read
INFO: task syz-executor4:12662 blocked for more than 120 seconds.
      Not tainted 4.9.87-g97d7f1c #54
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor4   D28752 12662   3869 0x00000004
 ffff8801d8a58000 ffff8801cd140a80 ffff8801cd4f24c0 ffff8801bcd66000
 ffff8801db321b98 ffff8801d896f4a0 ffffffff838a5adb 0000000041b58ab3
 ffffffff84193c70 00ffffff8123c1a0 ffff8801db322468 ffff8801db322490
Call Trace:
 [<ffffffff838a707f>] schedule+0x7f/0x1b0 kernel/sched/core.c:3550
 [<ffffffff838b31dc>] schedule_timeout+0x56c/0x10b0 kernel/time/timer.c:1768
 [<ffffffff838a528e>] io_schedule_timeout+0x1be/0x390 kernel/sched/core.c:5172
 [<ffffffff838a84f9>] io_schedule include/linux/sched.h:460 [inline]
 [<ffffffff838a84f9>] bit_wait_io+0x19/0xa0 kernel/sched/wait.c:582
 [<ffffffff838a7bd7>] __wait_on_bit+0x57/0x120 kernel/sched/wait.c:383
 [<ffffffff81432874>] wait_on_page_bit+0xf4/0x140 mm/filemap.c:802
 [<ffffffff81432a81>] wait_on_page_writeback include/linux/pagemap.h:526 [inline]
 [<ffffffff81432a81>] __filemap_fdatawait_range+0x1c1/0x2b0 mm/filemap.c:453
 [<ffffffff81432b95>] filemap_fdatawait_range+0x25/0x50 mm/filemap.c:483
 [<ffffffff8143b8d4>] filemap_write_and_wait_range+0x74/0xb0 mm/filemap.c:584
 [<ffffffff8143ba5a>] generic_file_direct_write+0x14a/0x500 mm/filemap.c:2618
 [<ffffffff8143c02f>] __generic_file_write_iter+0x21f/0x570 mm/filemap.c:2823
 [<ffffffff8162d6ec>] blkdev_write_iter+0x1bc/0x380 fs/block_dev.c:1718
 [<ffffffff8156e723>] do_iter_readv_writev+0x3d3/0x4b0 fs/read_write.c:695
 [<ffffffff81570c76>] do_readv_writev+0x2e6/0x740 fs/read_write.c:871
 [<ffffffff81571607>] vfs_writev+0x87/0xc0 fs/read_write.c:910
 [<ffffffff815719a5>] do_pwritev+0x115/0x1a0 fs/read_write.c:997
 [<ffffffff81574870>] SYSC_pwritev fs/read_write.c:1044 [inline]
 [<ffffffff81574870>] SyS_pwritev+0x30/0x40 fs/read_write.c:1039
 [<ffffffff81006504>] do_syscall_64+0x1a4/0x490 arch/x86/entry/common.c:282
 [<ffffffff838b6b53>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb

Showing all locks held in the system:
2 locks held by khungtaskd/514:
 #0:  (rcu_read_lock){......}, at: [<ffffffff81373315>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff81373315>] watchdog+0x125/0xa70 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff81238300>] debug_show_all_locks+0x70/0x280 kernel/locking/lockdep.c:4336
3 locks held by kworker/u4:3/1610:
 #0:  ("writeback"){++++.+}, at: [<ffffffff81189922>] work_static include/linux/workqueue.h:186 [inline]
 #0:  ("writeback"){++++.+}, at: [<ffffffff81189922>] set_work_data kernel/workqueue.c:617 [inline]
 #0:  ("writeback"){++++.+}, at: [<ffffffff81189922>] set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0:  ("writeback"){++++.+}, at: [<ffffffff81189922>] process_one_work+0x6f2/0x1610 kernel/workqueue.c:2085
 #1:  ((&(&wb->dwork)->work)){+.+.+.}, at: [<ffffffff8118995c>] process_one_work+0x72c/0x1610 kernel/workqueue.c:2089
 #2:  (&type->s_umount_key#22){.+.+..}, at: [<ffffffff81579f90>] trylock_super+0x20/0x100 fs/super.c:393
1 lock held by rsyslogd/3652:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff815d3edf>] __fdget_pos+0x9f/0xc0 fs/file.c:781
2 locks held by getty/3781:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff838b4d52>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+.+.}, at: [<ffffffff8200af14>] n_tty_read+0x1f4/0x16c0 drivers/tty/n_tty.c:2133

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

NMI backtrace for cpu 1
CPU: 1 PID: 514 Comm: khungtaskd Not tainted 4.9.87-g97d7f1c #54
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d87b7d00 ffffffff81d95a19 0000000000000000 0000000000000001
 0000000000000001 0000000000000001 ffffffff810bb230 ffff8801d87b7d38
 ffffffff81da0b3d 0000000000000001 0000000000000000 ffff8801ba088418
Call Trace:
 [<ffffffff81d95a19>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d95a19>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81da0b3d>] nmi_cpu_backtrace+0xfd/0x120 lib/nmi_backtrace.c:99
 [<ffffffff81da0c77>] nmi_trigger_cpumask_backtrace+0x117/0x190 lib/nmi_backtrace.c:60
 [<ffffffff810bb324>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff813738e0>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff813738e0>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff813738e0>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff813738e0>] watchdog+0x6f0/0xa70 kernel/hung_task.c:239
 [<ffffffff8119a92d>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff838b6cec>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:374
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at pc 0xffffffff838b57c6

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/03/14 10:09 https://android.googlesource.com/kernel/common android-4.9 97d7f1c7c0f0 08dacaa0 .config console log report ci-android-49-kasan-gce
2018/04/16 22:04 https://android.googlesource.com/kernel/common android-4.9 8683408f8e81 802ac912 .config console log report ci-android-49-kasan-gce-386
2018/03/24 00:42 https://android.googlesource.com/kernel/common android-4.9 ebc27895e954 2e9d9054 .config console log report ci-android-49-kasan-gce-386
* Struck through repros no longer work on HEAD.