syzbot


INFO: task hung in __blkdev_direct_IO_simple

Status: closed as dup on 2017/12/12 16:44
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+351690c704439fdf063697b93591b48688cb9043@syzkaller.appspotmail.com
First crash: 2299d, last: 2114d
Duplicate of
Title Repro Cause bisect Fix bisect Count Last Reported
INFO: task hung in lo_ioctl block 47 2174d 2290d

Sample crash report:
INFO: task syz-executor2:7537 blocked for more than 120 seconds.
      Not tainted 4.17.0+ #83
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor2   D20088  7537   4598 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2876 [inline]
 __schedule+0x801/0x1e30 kernel/sched/core.c:3518
 schedule+0xef/0x430 kernel/sched/core.c:3562
 io_schedule+0x1c/0x70 kernel/sched/core.c:5182
 __blkdev_direct_IO_simple+0x7fc/0xfb0 fs/block_dev.c:241
 blkdev_direct_IO+0xb46/0x10e0 fs/block_dev.c:428
 generic_file_read_iter+0x510/0x2f00 mm/filemap.c:2341
 blkdev_read_iter+0x120/0x190 fs/block_dev.c:1930
 call_read_iter include/linux/fs.h:1778 [inline]
 generic_file_splice_read+0x552/0x910 fs/splice.c:307
 do_splice_to+0x12e/0x190 fs/splice.c:880
 splice_direct_to_actor+0x268/0x8d0 fs/splice.c:952
 do_splice_direct+0x2cc/0x400 fs/splice.c:1061
 do_sendfile+0x60f/0xe00 fs/read_write.c:1440
 __do_sys_sendfile64 fs/read_write.c:1495 [inline]
 __se_sys_sendfile64 fs/read_write.c:1487 [inline]
 __x64_sys_sendfile64+0x155/0x240 fs/read_write.c:1487
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x455a09
RSP: 002b:00007fb973522c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007fb9735236d4 RCX: 0000000000455a09
RDX: 0000000020000040 RSI: 0000000000000013 RDI: 0000000000000013
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 000000001b7889b2 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000005a5 R14: 00000000006fd818 R15: 0000000000000000

Showing all locks held in the system:
2 locks held by khungtaskd/892:
 #0: 00000000a1a53a66 (rcu_read_lock){....}, at: check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline]
 #0: 00000000a1a53a66 (rcu_read_lock){....}, at: watchdog+0x1ff/0xf60 kernel/hung_task.c:249
 #1: 0000000058f20940 (tasklist_lock){.+.+}, at: debug_show_all_locks+0xde/0x34a kernel/locking/lockdep.c:4470
1 lock held by rsyslogd/4431:
 #0: 00000000e5d9fe46 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1a9/0x1e0 fs/file.c:766
2 locks held by getty/4522:
 #0: 000000003c52e76d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1: 00000000c44362cb (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
2 locks held by getty/4523:
 #0: 0000000092451c7b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1: 000000004ce25b6a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
2 locks held by getty/4524:
 #0: 00000000a43ecc6b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1: 000000009cafe530 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
2 locks held by getty/4525:
 #0: 000000004ebda64b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1: 0000000007f560cf (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
2 locks held by getty/4526:
 #0: 000000005978dcf3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1: 00000000fa86e638 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
2 locks held by getty/4527:
 #0: 000000000a3d4c4d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1: 0000000049dda11f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
2 locks held by getty/4528:
 #0: 00000000ca136047 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1: 00000000e2f99769 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131

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

NMI backtrace for cpu 1
CPU: 1 PID: 892 Comm: khungtaskd Not tainted 4.17.0+ #83
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1b9/0x294 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold.4+0x19/0xce lib/nmi_backtrace.c:103
 nmi_trigger_cpumask_backtrace+0x151/0x192 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+0xc10/0xf60 kernel/hung_task.c:249
 kthread+0x345/0x410 kernel/kthread.c:240
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412
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 (365):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/06/05 04:04 upstream 910470e03f34 a50d873b .config console log report ci-upstream-kasan-gce
2018/05/28 21:24 upstream 786b71f5b754 f48c20b8 .config console log report ci-upstream-kasan-gce
2018/05/21 10:24 upstream 771c577c23ba f48c20b8 .config console log report ci-upstream-kasan-gce
2018/05/20 02:30 upstream 0b449a441dac f48c20b8 .config console log report ci-upstream-kasan-gce
2018/04/16 07:17 upstream 71b8ebbf3d7b 7a67784c .config console log report ci-upstream-kasan-gce
2018/04/10 17:07 upstream c18bb396d3d2 8e873e9d .config console log report ci-upstream-kasan-gce
2018/04/05 05:45 upstream 3e968c9f1401 676bd07e .config console log report ci-upstream-kasan-gce
2018/04/03 12:08 upstream 642e7fd23353 676bd07e .config console log report ci-upstream-kasan-gce
2018/03/30 15:52 upstream c2a9838452a4 d47f0ed6 .config console log report ci-upstream-kasan-gce-root
2018/03/30 13:36 upstream c2a9838452a4 d47f0ed6 .config console log report ci-upstream-kasan-gce
2018/03/29 06:44 upstream a2601d78b77a bf5e585c .config console log report ci-upstream-kasan-gce
2018/03/28 16:17 upstream 3eb2ce825ea1 bf5e585c .config console log report ci-upstream-kasan-gce-root
2018/03/28 12:39 upstream 3eb2ce825ea1 bf5e585c .config console log report ci-upstream-kasan-gce
2018/03/28 05:49 upstream 3eb2ce825ea1 bf5e585c .config console log report ci-upstream-kasan-gce
2018/03/28 04:46 upstream 3eb2ce825ea1 bf5e585c .config console log report ci-upstream-kasan-gce
2018/03/27 14:37 upstream 3eb2ce825ea1 bf5e585c .config console log report ci-upstream-kasan-gce-root
2018/03/20 17:05 upstream 1b5f3ba415fe 72c33b66 .config console log report ci-upstream-kasan-gce
2018/02/09 12:48 upstream f1517df8701c 9fb5ec43 .config console log report ci-upstream-kasan-gce
2018/06/01 17:12 upstream 0512e0134582 2f93b54f .config console log report ci-upstream-kasan-gce-386
2018/05/24 13:54 upstream bee797529d7c f48c20b8 .config console log report ci-upstream-kasan-gce-386
2018/05/17 04:35 upstream e6506eb24187 a367c1d7 .config console log report ci-upstream-kasan-gce-386
2018/05/16 04:39 upstream eeba2dfa6a0d 68ce85f1 .config console log report ci-upstream-kasan-gce-386
2018/03/29 04:11 upstream a2601d78b77a bf5e585c .config console log report ci-upstream-kasan-gce-386
2018/03/28 09:54 upstream 3eb2ce825ea1 bf5e585c .config console log report ci-upstream-kasan-gce-386
2018/03/22 03:29 upstream 3215b9d57a2c 95c88d7a .config console log report ci-upstream-kasan-gce-386
2018/03/21 15:17 upstream 3215b9d57a2c f63eeee9 .config console log report ci-upstream-kasan-gce-386
2018/03/19 19:48 upstream c698ca527893 7e7d7ed2 .config console log report ci-upstream-kasan-gce-386
2018/03/19 04:22 upstream 9e1909b9da04 08dacaa0 .config console log report ci-upstream-kasan-gce-386
2018/03/18 16:09 upstream 8f5fd927c3a7 08dacaa0 .config console log report ci-upstream-kasan-gce-386
2018/03/13 15:52 upstream fc6eabbbf8ef 08dacaa0 .config console log report ci-upstream-kasan-gce-386
2018/03/12 01:15 upstream abeb75218aeb 36d1c454 .config console log report ci-upstream-kasan-gce-386
2018/03/11 18:05 upstream 3266b5bd97ea 36d1c454 .config console log report ci-upstream-kasan-gce-386
2018/03/10 23:17 upstream 3266b5bd97ea 36d1c454 .config console log report ci-upstream-kasan-gce-386
2018/03/03 12:18 upstream 0573fed92b67 2c6f473e .config console log report ci-upstream-kasan-gce-386
2018/03/03 05:54 upstream 0573fed92b67 2c6f473e .config console log report ci-upstream-kasan-gce-386
2018/03/03 02:27 upstream 0573fed92b67 2c6f473e .config console log report ci-upstream-kasan-gce-386
2018/03/02 05:50 upstream 8da5db7ddae1 2c6f473e .config console log report ci-upstream-kasan-gce-386
2018/03/01 03:52 upstream c02be2334e75 05b5a32c .config console log report ci-upstream-kasan-gce-386
2018/02/28 16:17 upstream f3afe530d644 05b5a32c .config console log report ci-upstream-kasan-gce-386
2018/02/27 07:52 upstream 4a3928c6f8a5 b370d4a7 .config console log report ci-upstream-kasan-gce-386
2018/02/25 00:54 upstream 9cb9c07d6b0c 5c1e0207 .config console log report ci-upstream-kasan-gce-386
2018/02/24 03:04 upstream 938e1426e262 5c1e0207 .config console log report ci-upstream-kasan-gce-386
2018/02/15 19:19 upstream 1388c80438e6 c8b3f7c1 .config console log report ci-upstream-kasan-gce-386
2018/01/21 23:28 mmots 2734fabdcba4 fbbdcd92 .config console log report ci-upstream-mmots-kasan-gce
2018/01/20 12:11 linux-next 761914dd2975 fbbdcd92 .config console log report ci-upstream-next-kasan-gce
* Struck through repros no longer work on HEAD.