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INFO: task hung in vt_ioctl (6)

Status: auto-obsoleted due to no activity on 2025/11/16 03:48
Subsystems: kernel
[Documentation on labels]
First crash: 113d, last: 113d
▶ ▼ Similar bugs (7)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.6 INFO: task hung in vt_ioctl 1 1 37d 37d 0/2 upstream: reported on 2025/11/02 14:54
upstream INFO: task hung in vt_ioctl (4) serial 1 1 811d 811d 0/29 auto-obsoleted due to no activity on 2023/12/19 05:20
linux-4.19 INFO: task hung in vt_ioctl 1 1 2022d 2022d 0/1 auto-closed as invalid on 2020/09/24 20:12
upstream INFO: task hung in vt_ioctl (3) serial 1 1 991d 991d 0/29 auto-obsoleted due to no activity on 2023/06/22 09:16
upstream INFO: task hung in vt_ioctl serial 1 1 2116d 2116d 0/29 auto-closed as invalid on 2020/05/23 20:53
upstream INFO: task hung in vt_ioctl (2) serial 1 2 1985d 2024d 0/29 auto-closed as invalid on 2020/10/01 08:58
upstream INFO: task hung in vt_ioctl (5) kernel 1 1 276d 276d 0/29 auto-obsoleted due to no activity on 2025/06/06 19:57

Sample crash report:
INFO: task syz.0.1237:15413 blocked for more than 143 seconds.
      Not tainted 6.17.0-rc1-syzkaller-00224-g8d561baae505 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1237      state:D stack:29032 pid:15413 tgid:15409 ppid:5847   task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1190/0x5de0 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:7058
 schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75
 ___down_common+0x2d8/0x460 kernel/locking/semaphore.c:268
 __down_common kernel/locking/semaphore.c:293 [inline]
 __down+0x20/0x30 kernel/locking/semaphore.c:303
 down+0x74/0xa0 kernel/locking/semaphore.c:100
 console_lock+0x5b/0xa0 kernel/printk/printk.c:2849
 vt_ioctl+0x2ddb/0x30a0 drivers/tty/vt/vt_ioctl.c:920
 tty_ioctl+0x65e/0x1680 drivers/tty/tty_io.c:2792
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:598 [inline]
 __se_sys_ioctl fs/ioctl.c:584 [inline]
 __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:584
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f10d6b8ebe9
RSP: 002b:00007f10d7a95038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f10d6db6180 RCX: 00007f10d6b8ebe9
RDX: 0000200000000140 RSI: 0000000000005609 RDI: 0000000000000009
RBP: 00007f10d6c11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f10d6db6218 R14: 00007f10d6db6180 R15: 00007ffdf5552d88
 </TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.17.0-rc1-syzkaller-00224-g8d561baae505 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
 watchdog+0xf0e/0x1260 kernel/hung_task.c:491
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5955 Comm: kworker/0:3 Not tainted 6.17.0-rc1-syzkaller-00224-g8d561baae505 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: wg-kex-wg2 wg_packet_handshake_receive_worker
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x8/0x20 kernel/kcov.c:314
Code: bf 03 00 00 00 e9 58 fe ff ff 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 0c 24 <89> f2 89 fe bf 05 00 00 00 e9 2a fe ff ff 66 2e 0f 1f 84 00 00 00
RSP: 0018:ffffc900000069f0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff88802adcbc58 RCX: ffffffff8a4459af
RDX: ffff88802ec84880 RSI: 0000000000000000 RDI: 0000000000000000
RBP: dffffc0000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000080 R11: 0000000000002c10 R12: ffff888074d34500
R13: ffffc90000006a90 R14: fffff52000000d53 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8881246bc000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555607875c8 CR3: 0000000032604000 CR4: 00000000003526f0
DR0: 0000000000000680 DR1: 0000000000000003 DR2: 0000000000000007
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 fib6_node_lookup_1+0x11f/0x9d0 net/ipv6/ip6_fib.c:1625
 fib6_node_lookup+0xdb/0x190 net/ipv6/ip6_fib.c:1695
 fib6_table_lookup+0xb1/0xa30 net/ipv6/route.c:2229
 ip6_pol_route+0x1cc/0x1230 net/ipv6/route.c:2269
 pol_lookup_func include/net/ip6_fib.h:617 [inline]
 fib6_rule_lookup+0x536/0x720 net/ipv6/fib6_rules.c:120
 ip6_route_input_lookup net/ipv6/route.c:2338 [inline]
 ip6_route_input+0x662/0xc00 net/ipv6/route.c:2641
 ip6_rcv_finish_core.constprop.0+0x1a0/0x5d0 net/ipv6/ip6_input.c:66
 ip6_rcv_finish+0x130/0x580 net/ipv6/ip6_input.c:77
 ip_sabotage_in+0x21e/0x290 net/bridge/br_netfilter_hooks.c:993
 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
 nf_hook_slow+0xbe/0x200 net/netfilter/core.c:623
 nf_hook.constprop.0+0x422/0x750 include/linux/netfilter.h:273
 NF_HOOK include/linux/netfilter.h:316 [inline]
 ipv6_rcv+0xa4/0x650 net/ipv6/ip6_input.c:311
 __netif_receive_skb_one_core+0x12d/0x1e0 net/core/dev.c:5979
 __netif_receive_skb+0x1d/0x160 net/core/dev.c:6092
 netif_receive_skb_internal net/core/dev.c:6178 [inline]
 netif_receive_skb+0x137/0x7b0 net/core/dev.c:6237
 NF_HOOK include/linux/netfilter.h:318 [inline]
 NF_HOOK include/linux/netfilter.h:312 [inline]
 br_pass_frame_up+0x346/0x490 net/bridge/br_input.c:70
 br_handle_frame_finish+0xf5a/0x1ca0 net/bridge/br_input.c:227
 br_nf_hook_thresh+0x307/0x410 net/bridge/br_netfilter_hooks.c:1170
 br_nf_pre_routing_finish_ipv6+0x76a/0xfb0 net/bridge/br_netfilter_ipv6.c:154
 NF_HOOK include/linux/netfilter.h:318 [inline]
 br_nf_pre_routing_ipv6+0x3cd/0x8c0 net/bridge/br_netfilter_ipv6.c:184
 br_nf_pre_routing+0x860/0x15b0 net/bridge/br_netfilter_hooks.c:508
 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
 nf_hook_bridge_pre net/bridge/br_input.c:283 [inline]
 br_handle_frame+0xad8/0x14b0 net/bridge/br_input.c:434
 __netif_receive_skb_core.constprop.0+0xa25/0x48c0 net/core/dev.c:5866
 __netif_receive_skb_one_core+0xb0/0x1e0 net/core/dev.c:5977
 __netif_receive_skb+0x1d/0x160 net/core/dev.c:6092
 process_backlog+0x442/0x15e0 net/core/dev.c:6444
 __napi_poll.constprop.0+0xba/0x550 net/core/dev.c:7494
 napi_poll net/core/dev.c:7557 [inline]
 net_rx_action+0xa9f/0xfe0 net/core/dev.c:7684
 handle_softirqs+0x216/0x8e0 kernel/softirq.c:579
 do_softirq kernel/softirq.c:480 [inline]
 do_softirq+0xb2/0xf0 kernel/softirq.c:467
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:407
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 fpregs_unlock arch/x86/include/asm/fpu/api.h:77 [inline]
 kernel_fpu_end+0x5e/0x70 arch/x86/kernel/fpu/core.c:479
 blake2s_compress+0x7f/0xe0 lib/crypto/x86/blake2s-glue.c:46
 blake2s_update+0xef/0x360 lib/crypto/blake2s.c:33
 hmac.constprop.0+0x23f/0x420 drivers/net/wireguard/noise.c:324
 kdf.constprop.0+0x1a1/0x280 drivers/net/wireguard/noise.c:375
 derive_keys drivers/net/wireguard/noise.c:397 [inline]
 wg_noise_handshake_begin_session+0x325/0xe80 drivers/net/wireguard/noise.c:838
 wg_packet_send_handshake_response+0x216/0x310 drivers/net/wireguard/send.c:96
 wg_receive_handshake_packet+0x247/0xbf0 drivers/net/wireguard/receive.c:154
 wg_packet_handshake_receive_worker+0x17f/0x3a0 drivers/net/wireguard/receive.c:213
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3236
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/08/18 03:46 upstream 8d561baae505 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in vt_ioctl
* Struck through repros no longer work on HEAD.