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INFO: task hung in vcs_open (5)

Status: auto-obsoleted due to no activity on 2023/06/04 04:45
Subsystems: serial
[Documentation on labels]
First crash: 427d, last: 423d
Similar bugs (8)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in vcs_open (3) serial 1 1166d 1166d 0/26 auto-closed as invalid on 2021/05/22 19:06
upstream INFO: task hung in vcs_open serial 32 1336d 1469d 0/26 closed as dup on 2020/08/05 10:53
upstream INFO: task hung in vcs_open (2) serial 1 1316d 1316d 0/26 auto-closed as invalid on 2020/12/23 12:34
linux-4.19 INFO: task hung in vcs_open 11 1272d 1585d 0/1 auto-closed as invalid on 2021/03/07 01:31
upstream INFO: task hung in vcs_open (4) serial 2 577d 640d 0/26 auto-obsoleted due to no activity on 2023/01/02 16:56
linux-4.14 INFO: task hung in vcs_open 3 1430d 1514d 0/1 auto-closed as invalid on 2020/09/30 10:12
upstream INFO: task hung in vcs_open (6) serial 2 196d 260d 0/26 auto-obsoleted due to no activity on 2024/01/17 08:03
linux-4.19 INFO: task hung in vcs_open (2) 1 555d 555d 0/1 auto-obsoleted due to no activity on 2023/02/22 05:12

Sample crash report:
INFO: task syz-executor.5:21251 blocked for more than 143 seconds.
      Not tainted 6.2.0-syzkaller-13563-gf915322fe014 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.5  state:D
 stack:28448 pid:21251 ppid:5129   flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5304 [inline]
 __schedule+0xcce/0x5b20 kernel/sched/core.c:6622
 schedule+0xde/0x1a0 kernel/sched/core.c:6698
 schedule_timeout+0x276/0x2b0 kernel/time/timer.c:2143
 ___down_common kernel/locking/semaphore.c:225 [inline]
 __down_common+0x3b2/0x8b0 kernel/locking/semaphore.c:246
 down+0x74/0xa0 kernel/locking/semaphore.c:63
 console_lock+0x2c/0x80 kernel/printk/printk.c:2609
 vcs_open+0x66/0xc0 drivers/tty/vt/vc_screen.c:756
 chrdev_open+0x26a/0x770 fs/char_dev.c:414
 do_dentry_open+0x6cc/0x13f0 fs/open.c:920
 do_open fs/namei.c:3560 [inline]
 path_openat+0x1baa/0x2750 fs/namei.c:3715
 do_filp_open+0x1ba/0x410 fs/namei.c:3742
 do_sys_openat2+0x16d/0x4c0 fs/open.c:1348
 do_sys_open fs/open.c:1364 [inline]
 __do_sys_openat fs/open.c:1380 [inline]
 __se_sys_openat fs/open.c:1375 [inline]
 __x64_sys_openat+0x143/0x1f0 fs/open.c:1375
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fad2368c0f9
RSP: 002b:00007fad2445a168 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fad237ac050 RCX: 00007fad2368c0f9
RDX: 0000000000000000 RSI: 0000000020000040 RDI: ffffffffffffff9c
RBP: 00007fad236e7ae9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fad238cfb1f R14: 00007fad2445a300 R15: 0000000000022000
 </TASK>

Showing all locks held in the system:
3 locks held by kworker/u4:0/9:
3 locks held by kworker/u4:1/11:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8c794eb0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x31/0xd80 kernel/rcu/tasks.h:510
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8c794bb0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x31/0xd80 kernel/rcu/tasks.h:510
2 locks held by kworker/1:1/26:
 #0: 
ffff888012472538
 (
(wq_completion)rcu_gp
){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline]
){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:639 [inline]
){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:666 [inline]
){+.+.}-{0:0}, at: process_one_work+0x86d/0x1820 kernel/workqueue.c:2361
 #1: 
ffffc90000a1fda8
 (
(work_completion)(&rew->rew_work)){+.+.}-{0:0}
, at: process_one_work+0x8a1/0x1820 kernel/workqueue.c:2365
1 lock held by khungtaskd/28:
 #0: ffffffff8c795a00
 (
rcu_read_lock

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/03/06 04:37 upstream f915322fe014 f8902b57 .config console log report info ci-upstream-kasan-gce INFO: task hung in vcs_open
2023/03/02 03:50 upstream ee3f96b16468 f8902b57 .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.