syzbot


INFO: task hung in SyS_sync_file_range

Status: closed as invalid on 2018/09/02 04:43
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+e19265ff646b0be033eb@syzkaller.appspotmail.com
First crash: 2215d, last: 2208d
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 (2) 1 2213d 2213d 0/3 closed as invalid on 2018/09/02 04:50
android-49 INFO: task hung in SyS_sync_file_range 1 2218d 2218d 0/3 closed as invalid on 2018/03/27 11:14

Sample crash report:
Buffer I/O error on dev loop0, logical block 15, lost async page write
Buffer I/O error on dev loop0, logical block 16, lost async page write
Buffer I/O error on dev loop0, logical block 17, lost async page write
buffer_io_error: 46 callbacks suppressed
Buffer I/O error on dev loop0, logical block 64, async page read
INFO: task syz-executor2:5526 blocked for more than 120 seconds.
      Not tainted 4.16.0+ #376
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor2   D27568  5526   4488 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2862 [inline]
 __schedule+0x8fb/0x1ef0 kernel/sched/core.c:3440
 schedule+0xf5/0x430 kernel/sched/core.c:3499
 io_schedule+0x1c/0x70 kernel/sched/core.c:5115
 wait_on_page_bit_common+0x4b3/0x770 mm/filemap.c:1099
 wait_on_page_bit mm/filemap.c:1132 [inline]
 wait_on_page_writeback include/linux/pagemap.h:546 [inline]
 __filemap_fdatawait_range+0x282/0x430 mm/filemap.c:533
 file_fdatawait_range+0x47/0x60 mm/filemap.c:581
 SYSC_sync_file_range fs/sync.c:341 [inline]
 SyS_sync_file_range+0x1e3/0x210 fs/sync.c:283
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x4552d9
RSP: 002b:00007f0b1ec1bc68 EFLAGS: 00000246 ORIG_RAX: 0000000000000115
RAX: ffffffffffffffda RBX: 00007f0b1ec1c6d4 RCX: 00000000004552d9
RDX: 000000007fffffff RSI: 0000000000000002 RDI: 0000000000000013
RBP: 000000000072bf58 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000007 R11: 0000000000000246 R12: 00000000ffffffff
R13: 000000000000064c R14: 00000000006fc7c0 R15: 0000000000000001

Showing all locks held in the system:
2 locks held by khungtaskd/878:
 #0: 0000000057f80a5b (rcu_read_lock){....}, at: check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline]
 #0: 0000000057f80a5b (rcu_read_lock){....}, at: watchdog+0x1d6/0xd70 kernel/hung_task.c:249
 #1: 0000000077f25fe0 (tasklist_lock){.+.+}, at: debug_show_all_locks+0xd3/0x3d0 kernel/locking/lockdep.c:4470
1 lock held by rsyslogd/4315:
 #0: 00000000e6415ac0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x165/0x1a0 fs/file.c:765
2 locks held by getty/4406:
 #0: 00000000673a66e6 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1: 00000000ffda2029 (&tty->atomic_write_lock){+.+.}, at: tty_write_lock+0x21/0x60 drivers/tty/tty_io.c:884
2 locks held by getty/4407:
 #0: 00000000b49aabc3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1: 00000000dd9ccd2a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131
2 locks held by getty/4408:
 #0: 0000000058e4e779 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1: 00000000fa90ddc0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131
2 locks held by getty/4409:
 #0: 00000000a4692fa8 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1: 00000000a34ae4d4 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131
2 locks held by getty/4410:
 #0: 0000000042dc14d6 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1: 00000000f6363992 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131
2 locks held by getty/4411:
 #0: 00000000756dd6d2 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1: 00000000b41a2450 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131
2 locks held by getty/4412:
 #0: 000000009b9ce399 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1: 00000000a7abaeb9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131
3 locks held by kworker/u4:6/26522:
 #0: 00000000651d2334 ((wq_completion)"writeback"){+.+.}, at: __write_once_size include/linux/compiler.h:215 [inline]
 #0: 00000000651d2334 ((wq_completion)"writeback"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: 00000000651d2334 ((wq_completion)"writeback"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline]
 #0: 00000000651d2334 ((wq_completion)"writeback"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:57 [inline]
 #0: 00000000651d2334 ((wq_completion)"writeback"){+.+.}, at: set_work_data kernel/workqueue.c:619 [inline]
 #0: 00000000651d2334 ((wq_completion)"writeback"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline]
 #0: 00000000651d2334 ((wq_completion)"writeback"){+.+.}, at: process_one_work+0xb83/0x1c40 kernel/workqueue.c:2084
 #1: 000000002ac26354 ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0xbd9/0x1c40 kernel/workqueue.c:2088
 #2: 00000000a1963c7b (&type->s_umount_key#35){++++}, at: trylock_super+0x20/0x100 fs/super.c:395
1 lock held by blkid/5486:
 #0: 000000003f11c216 (&bdev->bd_mutex){+.+.}, at: blkdev_put+0x2a/0x4f0 fs/block_dev.c:1808
1 lock held by syz-executor1/5534:
 #0: 000000003f11c216 (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x176/0x13b0 fs/block_dev.c:1458
1 lock held by syz-executor5/5518:
 #0: 000000003f11c216 (&bdev->bd_mutex){+.+.}, at: iterate_bdevs+0xc8/0x260 fs/block_dev.c:2160
1 lock held by syz-executor5/5539:
 #0: 000000003f11c216 (&bdev->bd_mutex){+.+.}, at: iterate_bdevs+0xc8/0x260 fs/block_dev.c:2160

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

NMI backtrace for cpu 1
CPU: 1 PID: 878 Comm: khungtaskd Not tainted 4.16.0+ #376
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1a7/0x27d lib/dump_stack.c:53
 nmi_cpu_backtrace+0x1e0/0x220 lib/nmi_backtrace.c:103
 nmi_trigger_cpumask_backtrace+0x123/0x180 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_all_cpu_backtrace include/linux/nmi.h:138 [inline]
 check_hung_task kernel/hung_task.c:132 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:190 [inline]
 watchdog+0x969/0xd70 kernel/hung_task.c:249
 kthread+0x33c/0x400 kernel/kthread.c:238
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:406
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:54

Crashes (10):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/04/03 05:49 upstream 86bbbebac193 676bd07e .config console log report ci-upstream-kasan-gce
2018/04/02 15:03 upstream 0adb32858b0b dc889257 .config console log report ci-upstream-kasan-gce
2018/04/02 14:31 upstream 0adb32858b0b dc889257 .config console log report ci-upstream-kasan-gce
2018/04/02 06:59 upstream 0adb32858b0b dc889257 .config console log report ci-upstream-kasan-gce
2018/04/02 01:38 upstream 0adb32858b0b dc889257 .config console log report ci-upstream-kasan-gce
2018/04/01 15:00 upstream 10b84daddbec 0a78e248 .config console log report ci-upstream-kasan-gce
2018/04/01 08:09 upstream 10b84daddbec 0174c6c8 .config console log report ci-upstream-kasan-gce
2018/04/01 04:46 upstream 10b84daddbec 0174c6c8 .config console log report ci-upstream-kasan-gce
2018/04/01 01:37 upstream 10b84daddbec 0174c6c8 .config console log report ci-upstream-kasan-gce
2018/03/28 01:12 upstream 3eb2ce825ea1 bf5e585c .config console log report ci-upstream-kasan-gce
* Struck through repros no longer work on HEAD.