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INFO: task hung in vt_ioctl (3)

Status: auto-obsoleted due to no activity on 2023/06/22 09:16
Subsystems: serial
[Documentation on labels]
First crash: 409d, last: 409d
▶ ▼ Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in vt_ioctl (4) serial 1 229d 229d 0/26 auto-obsoleted due to no activity on 2023/12/19 05:20
linux-4.19 INFO: task hung in vt_ioctl 1 1440d 1440d 0/1 auto-closed as invalid on 2020/09/24 20:12
upstream INFO: task hung in vt_ioctl serial 1 1533d 1533d 0/26 auto-closed as invalid on 2020/05/23 20:53
upstream INFO: task hung in vt_ioctl (2) serial 2 1403d 1442d 0/26 auto-closed as invalid on 2020/10/01 08:58

Sample crash report:
INFO: task syz-executor.5:18955 blocked for more than 143 seconds.
      Not tainted 6.3.0-rc3-syzkaller-00031-g1e760fa3596e #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.5  state:D stack:28456 pid:18955 ppid:5557   flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5304 [inline]
 __schedule+0xc91/0x5770 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+0x345/0x680 kernel/locking/semaphore.c:246
 down+0x74/0xa0 kernel/locking/semaphore.c:63
 console_lock+0x2c/0x80 kernel/printk/printk.c:2609
 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:380 [inline]
 vt_ioctl+0x19ce/0x2df0 drivers/tty/vt/vt_ioctl.c:752
 tty_ioctl+0x773/0x16e0 drivers/tty/tty_io.c:2777
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __x64_sys_ioctl+0x197/0x210 fs/ioctl.c:856
 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: 0033:0x7f120b68c0f9
RSP: 002b:00007f120c4b7168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f120b7abf80 RCX: 00007f120b68c0f9
RDX: 0000000000000001 RSI: 0000000000004b3a RDI: 0000000000000003
RBP: 00007f120b6e7b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc40472b6f R14: 00007f120c4b7300 R15: 0000000000022000
 </TASK>
INFO: task syz-executor.5:18960 blocked for more than 143 seconds.
      Not tainted 6.3.0-rc3-syzkaller-00031-g1e760fa3596e #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.5  state:D stack:28264 pid:18960 ppid:5557   flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5304 [inline]
 __schedule+0xc91/0x5770 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+0x345/0x680 kernel/locking/semaphore.c:246
 down+0x74/0xa0 kernel/locking/semaphore.c:63
 console_lock+0x2c/0x80 kernel/printk/printk.c:2609
 con_install+0x92/0x630 drivers/tty/vt/vt.c:3330
 tty_driver_install_tty drivers/tty/tty_io.c:1303 [inline]
 tty_init_dev.part.0+0x9e/0x670 drivers/tty/tty_io.c:1415
 tty_init_dev include/linux/err.h:36 [inline]
 tty_open_by_driver drivers/tty/tty_io.c:2081 [inline]
 tty_open+0xb0e/0x1010 drivers/tty/tty_io.c:2128
 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: 0033:0x7f120b63e284
RSP: 002b:00007f120c495ca0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f120b7ac050 RCX: 00007f120b63e284
RDX: 0000000000000002 RSI: 00007f120c495d40 RDI: 00000000ffffff9c
RBP: 00007f120c495d40 R08: 0000000000000000 R09: 000000000000000e
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000002
R13: 00007ffc40472b6f R14: 00007f120c496300 R15: 0000000000022000
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8c794b70 (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: ffffffff8c794870 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x31/0xd80 kernel/rcu/tasks.h:510
1 lock held by khungtaskd/28:
 #0: ffffffff8c7956c0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x340 kernel/locking/lockdep.c:6495
2 locks held by getty/4758:
 #0: ffff88802c7b2098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x26/0x80 drivers/tty/tty_ldisc.c:244
 #1: ffffc900015a02f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xef4/0x13e0 drivers/tty/n_tty.c:2177
1 lock held by syz-fuzzer/5550:
3 locks held by kworker/u4:24/12772:
1 lock held by syz-executor.0/13501:
6 locks held by syz-executor.3/18457:
2 locks held by syz-executor.5/18960:
 #0: ffffffff8d229388 (tty_mutex){+.+.}-{3:3}, at: tty_open_by_driver drivers/tty/tty_io.c:2045 [inline]
 #0: ffffffff8d229388 (tty_mutex){+.+.}-{3:3}, at: tty_open+0x59c/0x1010 drivers/tty/tty_io.c:2128
 #1: ffff888095e271c0 (&tty->legacy_mutex){+.+.}-{3:3}, at: tty_init_dev.part.0+0x39/0x670 drivers/tty/tty_io.c:1414
1 lock held by syz-executor.5/19075:
 #0: ffffffff8d229388 (tty_mutex){+.+.}-{3:3}, at: tty_open_by_driver drivers/tty/tty_io.c:2045 [inline]
 #0: ffffffff8d229388 (tty_mutex){+.+.}-{3:3}, at: tty_open+0x59c/0x1010 drivers/tty/tty_io.c:2128
1 lock held by syz-executor.5/19076:
 #0: ffffffff8d229388 (tty_mutex){+.+.}-{3:3}, at: tty_open_by_driver drivers/tty/tty_io.c:2045 [inline]
 #0: ffffffff8d229388 (tty_mutex){+.+.}-{3:3}, at: tty_open+0x59c/0x1010 drivers/tty/tty_io.c:2128
1 lock held by syz-executor.5/19127:
 #0: ffffffff8d229388 (tty_mutex){+.+.}-{3:3}, at: tty_open_by_driver drivers/tty/tty_io.c:2045 [inline]
 #0: ffffffff8d229388 (tty_mutex){+.+.}-{3:3}, at: tty_open+0x59c/0x1010 drivers/tty/tty_io.c:2128
1 lock held by syz-executor.5/19128:
 #0: ffffffff8d229388 (tty_mutex){+.+.}-{3:3}, at: tty_open_by_driver drivers/tty/tty_io.c:2045 [inline]
 #0: ffffffff8d229388 (tty_mutex){+.+.}-{3:3}, at: tty_open+0x59c/0x1010 drivers/tty/tty_io.c:2128

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

NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.3.0-rc3-syzkaller-00031-g1e760fa3596e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x29c/0x350 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x2a4/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
 watchdog+0xe16/0x1090 kernel/hung_task.c:379
 kthread+0x2e8/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 13501 Comm: syz-executor.0 Not tainted 6.3.0-rc3-syzkaller-00031-g1e760fa3596e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
RIP: 0010:preempt_count_sub+0xbf/0x150 kernel/sched/core.c:5804
Code: d2 0f 85 8e 00 00 00 8b 15 8a a3 20 0d 85 d2 75 bd 48 c7 c6 40 de 4b 8a 48 c7 c7 80 de 4b 8a e8 37 13 f4 ff 0f 0b 5b c3 84 c0 <75> 99 e8 aa 5c b5 02 85 c0 74 99 48 c7 c0 ec ee 77 8e 48 ba 00 00
RSP: 0018:ffffc9000c85fa48 EFLAGS: 00000002
RAX: 0000000080000002 RBX: 0000000000000001 RCX: 0000000000000000
RDX: 0000000000000002 RSI: 0000000000000003 RDI: 0000000000000001
RBP: ffff88801df28000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
R13: ffff88801df28018 R14: 0000000008000001 R15: ffff8880371cc000
FS:  00007fc659ecb700(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c00115b000 CR3: 000000003df02000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 try_to_wake_up+0x100/0x1c40 kernel/sched/core.c:4281
 autoremove_wake_function+0x16/0x150 kernel/sched/wait.c:419
 io_wake_function+0xe6/0x2c0 io_uring/io_uring.c:2508
 __wake_up_common+0x147/0x650 kernel/sched/wait.c:107
 __wake_up_common_lock+0xd4/0x140 kernel/sched/wait.c:138
 __io_cqring_wake io_uring/io_uring.h:245 [inline]
 __io_cqring_wake io_uring/io_uring.h:232 [inline]
 io_cqring_wake io_uring/io_uring.h:252 [inline]
 io_cq_unlock_post+0x134/0x180 io_uring/io_uring.c:648
 __io_cqring_overflow_flush+0x327/0x7b0 io_uring/io_uring.c:697
 io_cqring_do_overflow_flush io_uring/io_uring.c:705 [inline]
 io_cqring_wait io_uring/io_uring.c:2629 [inline]
 __do_sys_io_uring_enter+0x1f5e/0x26e0 io_uring/io_uring.c:3503
 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: 0033:0x7fc65908c0f9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc659ecb168 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa
RAX: ffffffffffffffda RBX: 00007fc6591abf80 RCX: 00007fc65908c0f9
RDX: 0000000000001543 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007fc6590e7b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd3444e40f R14: 00007fc659ecb300 R15: 0000000000022000
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/03/24 09:09 upstream 1e760fa3596e f94b4a29 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in vt_ioctl
* Struck through repros no longer work on HEAD.