syzbot


INFO: task hung in vcs_open (6)

Status: auto-obsoleted due to no activity on 2024/01/17 08:03
Subsystems: serial
[Documentation on labels]
First crash: 455d, last: 391d
Similar bugs (10)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in vcs_open (5) serial 2 619d 623d 0/28 auto-obsoleted due to no activity on 2023/06/04 04:45
upstream INFO: task hung in vcs_open (3) serial 1 1361d 1361d 0/28 auto-closed as invalid on 2021/05/22 19:06
upstream INFO: task hung in vcs_open serial 32 1532d 1665d 0/28 closed as dup on 2020/08/05 10:53
upstream INFO: task hung in vcs_open (2) serial 1 1511d 1511d 0/28 auto-closed as invalid on 2020/12/23 12:34
upstream INFO: task hung in vcs_open (7) serial 1 241d 241d 0/28 auto-obsoleted due to no activity on 2024/06/15 13:53
linux-4.19 INFO: task hung in vcs_open 11 1468d 1780d 0/1 auto-closed as invalid on 2021/03/07 01:31
upstream INFO: task hung in vcs_open (4) serial 2 772d 835d 0/28 auto-obsoleted due to no activity on 2023/01/02 16:56
linux-4.14 INFO: task hung in vcs_open 3 1625d 1709d 0/1 auto-closed as invalid on 2020/09/30 10:12
linux-4.19 INFO: task hung in vcs_open (2) 1 751d 751d 0/1 auto-obsoleted due to no activity on 2023/02/22 05:12
upstream INFO: task hung in vcs_open (8) nilfs serial C inconclusive 7 42d 48d 28/28 fixed on 2024/11/12 23:31

Sample crash report:
INFO: task syz-executor.0:10757 blocked for more than 143 seconds.
      Not tainted 6.6.0-rc6-syzkaller-00043-gdd72f9c7e512 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0  state:D stack:28272 pid:10757 ppid:10742  flags:0x00000006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0xee1/0x5a10 kernel/sched/core.c:6695
 schedule+0xe7/0x1b0 kernel/sched/core.c:6771
 schedule_timeout+0x278/0x2c0 kernel/time/timer.c:2143
 ___down_common kernel/locking/semaphore.c:225 [inline]
 __down_common+0x327/0x6c0 kernel/locking/semaphore.c:246
 down+0x74/0xa0 kernel/locking/semaphore.c:63
 console_lock+0x96/0x150 kernel/printk/printk.c:2652
 vcs_open+0x64/0xc0 drivers/tty/vt/vc_screen.c:763
 chrdev_open+0x277/0x700 fs/char_dev.c:414
 do_dentry_open+0x88b/0x1730 fs/open.c:929
 do_open fs/namei.c:3639 [inline]
 path_openat+0x19af/0x29c0 fs/namei.c:3796
 do_filp_open+0x1de/0x430 fs/namei.c:3823
 do_sys_openat2+0x176/0x1e0 fs/open.c:1422
 do_sys_open fs/open.c:1437 [inline]
 __do_sys_openat fs/open.c:1453 [inline]
 __se_sys_openat fs/open.c:1448 [inline]
 __x64_sys_openat+0x175/0x210 fs/open.c:1448
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f3e2fe7cae9
RSP: 002b:00007f3e30b2d0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f3e2ff9bf80 RCX: 00007f3e2fe7cae9
RDX: 0000000000000000 RSI: 0000000020000c00 RDI: ffffffffffffff9c
RBP: 00007f3e2fec847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f3e2ff9bf80 R15: 00007ffdfd683b88
 </TASK>
INFO: task syz-executor.0:10758 blocked for more than 144 seconds.
      Not tainted 6.6.0-rc6-syzkaller-00043-gdd72f9c7e512 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0  state:D
 stack:28400 pid:10758 ppid:10742  flags:0x00000006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0xee1/0x5a10 kernel/sched/core.c:6695
 schedule+0xe7/0x1b0 kernel/sched/core.c:6771
 schedule_timeout+0x278/0x2c0 kernel/time/timer.c:2143
 ___down_common kernel/locking/semaphore.c:225 [inline]
 __down_common+0x327/0x6c0 kernel/locking/semaphore.c:246
 down+0x74/0xa0 kernel/locking/semaphore.c:63
 console_lock+0x96/0x150 kernel/printk/printk.c:2652
 vcs_open+0x64/0xc0 drivers/tty/vt/vc_screen.c:763
 chrdev_open+0x277/0x700 fs/char_dev.c:414
 do_dentry_open+0x88b/0x1730 fs/open.c:929
 do_open fs/namei.c:3639 [inline]
 path_openat+0x19af/0x29c0 fs/namei.c:3796
 do_filp_open+0x1de/0x430 fs/namei.c:3823
 do_sys_openat2+0x176/0x1e0 fs/open.c:1422
 do_sys_open fs/open.c:1437 [inline]
 __do_sys_openat fs/open.c:1453 [inline]
 __se_sys_openat fs/open.c:1448 [inline]
 __x64_sys_openat+0x175/0x210 fs/open.c:1448
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f3e2fe7cae9
RSP: 002b:00007f3e30b0c0c8 EFLAGS: 00000246
 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f3e2ff9c050 RCX: 00007f3e2fe7cae9
RDX: 0000000000000000 RSI: 0000000020000c00 RDI: ffffffffffffff9c
RBP: 00007f3e2fec847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f3e2ff9c050 R15: 00007ffdfd683b88
 </TASK>
INFO: task syz-executor.0:10759 blocked for more than 148 seconds.
      Not tainted 6.6.0-rc6-syzkaller-00043-gdd72f9c7e512 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0  state:D
 stack:28400 pid:10759 ppid:10742  flags:0x00000006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0xee1/0x5a10 kernel/sched/core.c:6695
 schedule+0xe7/0x1b0 kernel/sched/core.c:6771
 schedule_timeout+0x278/0x2c0 kernel/time/timer.c:2143
 ___down_common kernel/locking/semaphore.c:225 [inline]
 __down_common+0x327/0x6c0 kernel/locking/semaphore.c:246
 down+0x74/0xa0 kernel/locking/semaphore.c:63
 console_lock+0x96/0x150 kernel/printk/printk.c:2652
 vcs_open+0x64/0xc0 drivers/tty/vt/vc_screen.c:763
 chrdev_open+0x277/0x700 fs/char_dev.c:414
 do_dentry_open+0x88b/0x1730 fs/open.c:929
 do_open fs/namei.c:3639 [inline]
 path_openat+0x19af/0x29c0 fs/namei.c:3796
 do_filp_open+0x1de/0x430 fs/namei.c:3823
 do_sys_openat2+0x176/0x1e0 fs/open.c:1422
 do_sys_open fs/open.c:1437 [inline]
 __do_sys_openat fs/open.c:1453 [inline]
 __se_sys_openat fs/open.c:1448 [inline]
 __x64_sys_openat+0x175/0x210 fs/open.c:1448
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f3e2fe7cae9
RSP: 002b:00007f3e2e9fe0c8 EFLAGS: 00000246
 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f3e2ff9c120 RCX: 00007f3e2fe7cae9
RDX: 0000000000000000 RSI: 0000000020000c00 RDI: ffffffffffffff9c
RBP: 00007f3e2fec847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f3e2ff9c120 R15: 00007ffdfd683b88
 </TASK>

Showing all locks held in the system:
5 locks held by kworker/u4:0/11:
 #0: 
ffff888012c71938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x787/0x15c0 kernel/workqueue.c:2605
 #1: ffffc90000107d80 (
(work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: psi_task_switch+0x2d9/0x900 kernel/sched/psi.c:999
 #2: ffff8880b99297d8 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x5d/0x200 kernel/time/timer.c:999
 #3: ffffffff924f6ff8 (&obj_hash[i].lock
){-.-.}-{2:2}
, at: update_rq_clock_task kernel/sched/core.c:725 [inline]
, at: update_rq_clock kernel/sched/core.c:769 [inline]
, at: update_rq_clock+0x24a/0xb20 kernel/sched/core.c:750
 #4: 
ffffffff8ca6c768 (text_mutex){+.+.}-{3:3}, at: arch_jump_label_transform_apply+0x17/0x30 arch/x86/kernel/jump_label.c:145
1 lock held by khungtaskd/29:
 #0: ffffffff8cbab2e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:303 [inline]
 #0: ffffffff8cbab2e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:749 [inline]
 #0: ffffffff8cbab2e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6613
2 locks held by getty/4787:
 #0: ffff8880265a70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc5/0x1480 drivers/tty/n_tty.c:2206
2 locks held by kworker/0:4/5080:
 #0: ffff888012c72938 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x787/0x15c0 kernel/workqueue.c:2605
 #1: ffffc9000479fd80 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7e9/0x15c0 kernel/workqueue.c:2606
3 locks held by kworker/1:3/5099:
3 locks held by kworker/1:8/5114:
3 locks held by kworker/0:1/10288:
2 locks held by kworker/0:3/10547:
5 locks held by kworker/0:6/10848:
8 locks held by syz-executor.0/10928:
 #0: ffff88801b9a6410 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12f/0x250 fs/read_write.c:637
 #1: ffff88805788c488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x281/0x610 fs/kernfs/file.c:325
 #2: ffff888141fa3008 (kn->active#51){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2a4/0x610 fs/kernfs/file.c:326
 #3: ffffffff8dca4d28 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xd2/0x4b0 drivers/net/netdevsim/bus.c:209
 #4: 
ffff88801dd690e8
 (
&dev->mutex
){....}-{3:3}
, at: device_lock include/linux/device.h:992 [inline]
, at: __device_driver_lock drivers/base/dd.c:1095 [inline]
, at: device_release_driver_internal+0xa4/0x610 drivers/base/dd.c:1292
 #5: 
ffff88801dd6b250
 (
&devlink->lock_key
#17
){+.+.}-{3:3}
, at: nsim_drv_remove+0x4a/0x1d0 drivers/net/netdevsim/dev.c:1672
 #6: 

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/10/19 07:59 upstream dd72f9c7e512 342b9c55 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in vcs_open
2023/08/16 07:27 upstream 4853c74bd7ab 39990d51 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in vcs_open
* Struck through repros no longer work on HEAD.