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INFO: task hung in SyS_sync_file_range (2)

Status: closed as invalid on 2018/09/02 04:50
First crash: 2207d, last: 2207d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-49 INFO: task hung in SyS_sync_file_range 1 2211d 2211d 0/3 closed as invalid on 2018/03/27 11:14
upstream INFO: task hung in SyS_sync_file_range fs 10 2202d 2208d 0/26 closed as invalid on 2018/09/02 04:43

Sample crash report:
Buffer I/O error on dev loop0, logical block 1, lost async page write
INFO: task syz-executor6:7173 blocked for more than 120 seconds.
      Not tainted 4.9.90-gdd1e37e #66
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor6   D29472  7173   3882 0x00000004
 ffff8801ca793000 0000000000000000 ffff8801cbd8e4c0 ffffffff84429880
 ffff8801db221b98 ffff8801c9d87a10 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
 [<ffffffff816160fb>] SYSC_sync_file_range fs/sync.c:346 [inline]
 [<ffffffff816160fb>] SyS_sync_file_range+0x1bb/0x220 fs/sync.c:283
 [<ffffffff81006504>] do_syscall_64+0x1a4/0x490 arch/x86/entry/common.c:282
 [<ffffffff838b8493>] 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: [<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
3 locks held by kworker/u4:3/1603:
 #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
1 lock held by rsyslogd/3655:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff815d2f5f>] __fdget_pos+0x9f/0xc0 fs/file.c:781
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 #66
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d8627d00 ffffffff81d94ee9 0000000000000000 0000000000000001
 0000000000000001 0000000000000001 ffffffff810bb920 ffff8801d8627d38
 ffffffff81da000d 0000000000000001 0000000000000000 ffff8801cba93418
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
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.9.90-gdd1e37e #66
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffffffff84429880 task.stack: ffffffff84400000
RIP: 0010:[<ffffffff811cb9c3>] c [<ffffffff811cb9c3>] llist_del_all include/linux/llist.h:210 [inline]
RIP: 0010:[<ffffffff811cb9c3>] c [<ffffffff811cb9c3>] sched_ttwu_pending+0x53/0x160 kernel/sched/core.c:1792
RSP: 0018:ffff8801db207f58  EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffff8801db221b80 RCX: 1ffffffff084007c
RDX: 0000000000000000 RSI: ffffffff83c18d80 RDI: ffffffff842003e0
RBP: ffff8801db207f98 R08: 0000000000000001 R09: ffff88021fffd008
R10: ffff88021fffd018 R11: ffff88021fffd010 R12: 0000000000021b80
R13: ffff8801db200000 R14: ffffffff84429880 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdd12264000 CR3: 00000001b84e2000 CR4: 0000000000160670
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffffffff812862b7c ffff8801db207f80c 0000000000000046c 0000000000021b80c
 0000000000021b80c ffff8801db200000c ffffffff84429880c 0000000000000000c
 ffff8801db207fd0c ffffffff811cbdb2c ffffffff84429880c ffffffff84200840c
Call Trace:
 [<ffffffff811cbdb2>] scheduler_ipi+0xc2/0x4f0 kernel/sched/core.c:1845
 [<ffffffff838bcbb6>] __smp_reschedule_interrupt arch/x86/kernel/smp.c:262 [inline]
 [<ffffffff838bcbb6>] smp_reschedule_interrupt+0x66/0x80 arch/x86/kernel/smp.c:269
 [<ffffffff838ba7d0>] reschedule_interrupt+0xa0/0xb0 arch/x86/entry/entry_64.S:671
 <EOI> d [<ffffffff838b7116>] ? native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:53
 [<ffffffff838b6745>] arch_safe_halt arch/x86/include/asm/paravirt.h:104 [inline]
 [<ffffffff838b6745>] default_idle+0x55/0x360 arch/x86/kernel/process.c:295
 [<ffffffff8106be0a>] arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:286
 [<ffffffff838b7556>] default_idle_call+0x36/0x60 kernel/sched/idle.c:97
 [<ffffffff81225520>] cpuidle_idle_call kernel/sched/idle.c:155 [inline]
 [<ffffffff81225520>] cpu_idle_loop kernel/sched/idle.c:248 [inline]
 [<ffffffff81225520>] cpu_startup_entry+0x2b0/0x380 kernel/sched/idle.c:303
 [<ffffffff838a4214>] rest_init+0x184/0x190 init/main.c:408
 [<ffffffff84a6f8b2>] start_kernel+0x684/0x6b9 init/main.c:663
 [<ffffffff84a6e29d>] x86_64_start_reservations+0x2a/0x2c arch/x86/kernel/head64.c:196
 [<ffffffff84a6e3df>] x86_64_start_kernel+0x140/0x163 arch/x86/kernel/head64.c:177
Code: cc0 c48 c8d c3c cc5 ce0 c03 c20 c84 c48 c89 cf9 c48 cc1 ce9 c03 c80 c3c c11 c00 c0f c85 cca c00 c00 c00 c48 c03 c1c cc5 ce0 c03 c20 c84 c31 cd2 c48 c87 c93 c50 c0b c00 c00 c<48> c85 cd2 c48 c89 c55 cd0 c0f c84 c9d c00 c00 c00 c4c c8d c73 c18 c48 c89 cdf c49 c

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/03/29 02:54 https://android.googlesource.com/kernel/common android-4.9 dd1e37e64645 bf5e585c .config console log report ci-android-49-kasan-gce
* Struck through repros no longer work on HEAD.