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INFO: task hung in generic_file_read_iter

Status: closed as invalid on 2018/03/27 11:14
First crash: 2213d, last: 2213d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in generic_file_read_iter (2) fs 2 2202d 2208d 0/26 auto-closed as invalid on 2019/02/22 10:22
upstream INFO: task hung in generic_file_read_iter fs 1 2214d 2214d 0/26 closed as invalid on 2018/03/27 11:14

Sample crash report:
binder: 29594:29622 ioctl 40046207 0 returned -16
binder: 29594:29622 transaction failed 29189/-22, size 0-0 line 3010
INFO: task syz-executor2:29602 blocked for more than 120 seconds.
      Not tainted 4.9.90-gdd1e37e #6
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor2   D26992 29602  23851 0x20020004
 ffff8801d835b000 ffff8801d744b480 ffff8801b78acfc0 ffff8801d960c800
 ffff8801db221b98 ffff8801c007f360 ffffffff838a75cb 0000000041b58ab3
 ffffffff84193d90 00ffffff8123aaf0 ffff8801db222468 ffff8801db222490
Call Trace:
 [<ffffffff838a8b6f>] schedule+0x7f/0x1b0 kernel/sched/core.c:3551
 [<ffffffff838b4b2c>] schedule_timeout+0x56c/0x10b0 kernel/time/timer.c:1768
 [<ffffffff838a6d7e>] io_schedule_timeout+0x1be/0x390 kernel/sched/core.c:5173
 [<ffffffff838a9fe9>] io_schedule include/linux/sched.h:460 [inline]
 [<ffffffff838a9fe9>] bit_wait_io+0x19/0xa0 kernel/sched/wait.c:582
 [<ffffffff838a96c7>] __wait_on_bit+0x57/0x120 kernel/sched/wait.c:383
 [<ffffffff814316e4>] wait_on_page_bit+0xf4/0x140 mm/filemap.c:802
 [<ffffffff814318f1>] wait_on_page_writeback include/linux/pagemap.h:526 [inline]
 [<ffffffff814318f1>] __filemap_fdatawait_range+0x1c1/0x2b0 mm/filemap.c:453
 [<ffffffff81431a05>] filemap_fdatawait_range+0x25/0x50 mm/filemap.c:483
 [<ffffffff8143a744>] filemap_write_and_wait_range+0x74/0xb0 mm/filemap.c:584
 [<ffffffff8143c093>] generic_file_read_iter+0x6d3/0x1ac0 mm/filemap.c:1945
 [<ffffffff8162b5e5>] blkdev_read_iter+0x105/0x170 fs/block_dev.c:1738
 [<ffffffff8160fe84>] generic_file_splice_read+0x294/0x510 fs/splice.c:309
 [<ffffffff8160e63a>] do_splice_to+0x10a/0x160 fs/splice.c:899
 [<ffffffff8160e8dd>] splice_direct_to_actor+0x24d/0x800 fs/splice.c:971
 [<ffffffff8160f037>] do_splice_direct+0x1a7/0x270 fs/splice.c:1080
 [<ffffffff8157200b>] do_sendfile+0x54b/0xd30 fs/read_write.c:1393
 [<ffffffff815740c1>] C_SYSC_sendfile fs/read_write.c:1469 [inline]
 [<ffffffff815740c1>] compat_SyS_sendfile+0xd1/0x160 fs/read_write.c:1458
 [<ffffffff81006f95>] do_syscall_32_irqs_on arch/x86/entry/common.c:325 [inline]
 [<ffffffff81006f95>] do_fast_syscall_32+0x2f5/0x870 arch/x86/entry/common.c:387
 [<ffffffff838b9bd0>] entry_SYSENTER_compat+0x90/0xa2 arch/x86/entry/entry_64_compat.S:137

Showing all locks held in the system:
3 locks held by kworker/u4:0/6:
 #0:  ("writeback"){++++.+}, at: [<ffffffff8118af42>] work_static include/linux/workqueue.h:186 [inline]
 #0:  ("writeback"){++++.+}, at: [<ffffffff8118af42>] set_work_data kernel/workqueue.c:617 [inline]
 #0:  ("writeback"){++++.+}, at: [<ffffffff8118af42>] set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0:  ("writeback"){++++.+}, at: [<ffffffff8118af42>] process_one_work+0x6f2/0x1610 kernel/workqueue.c:2085
 #1:  ((&(&wb->dwork)->work)){+.+.+.}, at: [<ffffffff8118af7c>] process_one_work+0x72c/0x1610 kernel/workqueue.c:2089
 #2:  (&type->s_umount_key#22){++++..}, at: [<ffffffff815790a0>] trylock_super+0x20/0x100 fs/super.c:393
2 locks held by khungtaskd/515:
 #0:  (rcu_read_lock){......}, at: [<ffffffff81372185>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff81372185>] watchdog+0x125/0xa70 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff81236c50>] debug_show_all_locks+0x70/0x280 kernel/locking/lockdep.c:4336
2 locks held by getty/3783:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff838b66a2>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+.+.}, at: [<ffffffff8200a6a4>] n_tty_read+0x1f4/0x16c0 drivers/tty/n_tty.c:2133

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

NMI backtrace for cpu 1
CPU: 1 PID: 515 Comm: khungtaskd Not tainted 4.9.90-gdd1e37e #6
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d86cfd00 ffffffff81d94ee9 0000000000000000 0000000000000001
 0000000000000001 0000000000000001 ffffffff810bb920 ffff8801d86cfd38
 ffffffff81da000d 0000000000000001 0000000000000000 ffff8801d74ccc18
Call Trace:
 [<ffffffff81d94ee9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d94ee9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81da000d>] nmi_cpu_backtrace+0xfd/0x120 lib/nmi_backtrace.c:99
 [<ffffffff81da0147>] nmi_trigger_cpumask_backtrace+0x117/0x190 lib/nmi_backtrace.c:60
 [<ffffffff810bba14>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff81372750>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81372750>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81372750>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81372750>] watchdog+0x6f0/0xa70 kernel/hung_task.c:239
 [<ffffffff8119bf4d>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff838b865c>] 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 0xffffffff838b7116

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/03/26 13:53 https://android.googlesource.com/kernel/common android-4.9 dd1e37e64645 e033c1f1 .config console log report ci-android-49-kasan-gce-386
* Struck through repros no longer work on HEAD.