INFO: task hung in show_traces_open

Status: upstream: reported syz repro on 2026/10/06 06:56
Reported-by: syzbot+29e0b8d3e8d1b2f3c3e3@syzkaller.appspotmail.com
First crash: 16d, last: 12d
▶ ▼ Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: task hung in show_traces_open origin:lts-only 1 syz 12 12d 39d 0/3 upstream: reported syz repro on 2026/09/13 05:47

Sample crash report:
INFO: task syz.2.19:4395 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.19        state:D stack:26896 pid: 4395 ppid:  4324 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11c3/0x4350 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xdf5/0x2400 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 trace_array_get kernel/trace/trace.c:451 [inline]
 tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
 show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
 do_dentry_open+0x7f7/0xf90 fs/open.c:826
 do_open fs/namei.c:3659 [inline]
 path_openat+0x2718/0x2fb0 fs/namei.c:3793
 do_filp_open+0x1df/0x400 fs/namei.c:3820
 do_sys_openat2+0x14b/0x500 fs/open.c:1255
 do_sys_open fs/open.c:1271 [inline]
 __do_sys_openat fs/open.c:1287 [inline]
 __se_sys_openat fs/open.c:1282 [inline]
 __x64_sys_openat+0x135/0x160 fs/open.c:1282
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7efd3c5801d9
RSP: 002b:00007ffd87a03378 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007efd3c807fa0 RCX: 00007efd3c5801d9
RDX: 000000000000001b RSI: 0000200000000080 RDI: ffffffffffffff9c
RBP: 00007efd3c617888 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007efd3c807fac R14: 00007efd3c807fa0 R15: 00007efd3c807fa0
 </TASK>
INFO: task syz.1.18:4396 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.18        state:D stack:27088 pid: 4396 ppid:  4319 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11c3/0x4350 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xdf5/0x2400 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 trace_array_get kernel/trace/trace.c:451 [inline]
 tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
 show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
 do_dentry_open+0x7f7/0xf90 fs/open.c:826
 do_open fs/namei.c:3659 [inline]
 path_openat+0x2718/0x2fb0 fs/namei.c:3793
 do_filp_open+0x1df/0x400 fs/namei.c:3820
 do_sys_openat2+0x14b/0x500 fs/open.c:1255
 do_sys_open fs/open.c:1271 [inline]
 __do_sys_openat fs/open.c:1287 [inline]
 __se_sys_openat fs/open.c:1282 [inline]
 __x64_sys_openat+0x135/0x160 fs/open.c:1282
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fc806d361d9
RSP: 002b:00007fffe3656918 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fc806fbdfa0 RCX: 00007fc806d361d9
RDX: 000000000000001b RSI: 0000200000000080 RDI: ffffffffffffff9c
RBP: 00007fc806dcd888 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc806fbdfac R14: 00007fc806fbdfa0 R15: 00007fc806fbdfa0
 </TASK>
INFO: task syz.4.21:4397 blocked for more than 145 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.21        state:D stack:27472 pid: 4397 ppid:  4331 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11c3/0x4350 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xdf5/0x2400 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 trace_array_get kernel/trace/trace.c:451 [inline]
 tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
 show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
 do_dentry_open+0x7f7/0xf90 fs/open.c:826
 do_open fs/namei.c:3659 [inline]
 path_openat+0x2718/0x2fb0 fs/namei.c:3793
 do_filp_open+0x1df/0x400 fs/namei.c:3820
 do_sys_openat2+0x14b/0x500 fs/open.c:1255
 do_sys_open fs/open.c:1271 [inline]
 __do_sys_openat fs/open.c:1287 [inline]
 __se_sys_openat fs/open.c:1282 [inline]
 __x64_sys_openat+0x135/0x160 fs/open.c:1282
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fca1513e1d9
RSP: 002b:00007ffd23de2e68 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fca153c5fa0 RCX: 00007fca1513e1d9
RDX: 000000000000001b RSI: 0000200000000080 RDI: ffffffffffffff9c
RBP: 00007fca151d5888 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fca153c5fac R14: 00007fca153c5fa0 R15: 00007fca153c5fa0
 </TASK>
INFO: task syz.3.20:4398 blocked for more than 146 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.20        state:D
 stack:27088 pid: 4398 ppid:  4326 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11c3/0x4350 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xdf5/0x2400 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 trace_array_get kernel/trace/trace.c:451 [inline]
 tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
 show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
 do_dentry_open+0x7f7/0xf90 fs/open.c:826
 do_open fs/namei.c:3659 [inline]
 path_openat+0x2718/0x2fb0 fs/namei.c:3793
 do_filp_open+0x1df/0x400 fs/namei.c:3820
 do_sys_openat2+0x14b/0x500 fs/open.c:1255
 do_sys_open fs/open.c:1271 [inline]
 __do_sys_openat fs/open.c:1287 [inline]
 __se_sys_openat fs/open.c:1282 [inline]
 __x64_sys_openat+0x135/0x160 fs/open.c:1282
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fa3d2af61d9
RSP: 002b:00007ffefa871d38 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fa3d2d7dfa0 RCX: 00007fa3d2af61d9
RDX: 000000000000001b RSI: 0000200000000080 RDI: ffffffffffffff9c
RBP: 00007fa3d2b8d888 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa3d2d7dfac R14: 00007fa3d2d7dfa0 R15: 00007fa3d2d7dfa0
 </TASK>

Showing all locks held in the system:
3 locks held by kworker/1:1/23:
 #0: ffff88802c568138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
 #1: ffffc90000ddfd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
 #2: ffffffff8e24d5c8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xc4/0x1530 net/ipv6/addrconf.c:4128
1 lock held by khungtaskd/27:
 #0: ffffffff8d11efa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
3 locks held by kworker/u4:1/144:
2 locks held by getty/3947:
 #0: ffff88814c7ac098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x594/0x1a50 drivers/tty/n_tty.c:2158
2 locks held by kworker/1:3/4248:
 #0: ffff888017872138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
 #1: ffffc90002f4fd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
3 locks held by kworker/0:16/4312:
 #0: ffff88802c568138
 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x75c/0xff0 kernel/workqueue.c:-1
 #1: 
ffffc9000312fd00
 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x79e/0xff0 kernel/workqueue.c:2285
 #2: ffffffff8e24d5c8 (rtnl_mutex
){+.+.}-{3:3}, at: addrconf_dad_work+0xc4/0x1530 net/ipv6/addrconf.c:4128
5 locks held by syz.0.17/4363:
3 locks held by kworker/u4:6/4384:
1 lock held by syz.2.19/4395:
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: trace_array_get kernel/trace/trace.c:451 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
1 lock held by syz.1.18/4396:
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: trace_array_get kernel/trace/trace.c:451 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
1 lock held by syz.4.21/4397:
 #0: ffffffff8d1615a8 (
trace_types_lock){+.+.}-{3:3}
, at: trace_array_get kernel/trace/trace.c:451 [inline]
, at: tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
, at: show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
1 lock held by syz.3.20/4398:
 #0: 
ffffffff8d1615a8
 (
trace_types_lock
){+.+.}-{3:3}
, at: trace_array_get kernel/trace/trace.c:451 [inline]
, at: tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
, at: show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
1 lock held by syz.5.22/4421:
 #0: 
ffffffff8d1615a8
 (
trace_types_lock){+.+.}-{3:3}, at: trace_array_get kernel/trace/trace.c:451 [inline]
trace_types_lock){+.+.}-{3:3}, at: tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
trace_types_lock){+.+.}-{3:3}, at: show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
1 lock held by syz.6.23/4465:
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: trace_array_get kernel/trace/trace.c:451 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
1 lock held by syz.9.26/4503:
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: trace_array_get kernel/trace/trace.c:451 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
1 lock held by syz.7.24/4504:
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: trace_array_get kernel/trace/trace.c:451 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
1 lock held by syz.8.25/4505:
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: trace_array_get kernel/trace/trace.c:451 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
1 lock held by syz.2.32/4562:
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: trace_array_get kernel/trace/trace.c:451 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
1 lock held by syz.3.44/4608:
 #0: 
ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: trace_array_get kernel/trace/trace.c:451 [inline]
ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
1 lock held by syz.1.43/4609:
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: trace_array_get kernel/trace/trace.c:451 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
1 lock held by syz.4.45/4632:
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: trace_array_get kernel/trace/trace.c:451 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
1 lock held by syz.5.65/4648:
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: trace_array_get kernel/trace/trace.c:451 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
1 lock held by syz.6.88/4743:
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: trace_array_get kernel/trace/trace.c:451 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
1 lock held by syz.9.89/4744:
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: trace_array_get kernel/trace/trace.c:451 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
1 lock held by syz.7.98/4777:
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: trace_array_get kernel/trace/trace.c:451 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
1 lock held by syz.8.104/4782:
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: trace_array_get kernel/trace/trace.c:451 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
1 lock held by syz.3.130/4847:
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: trace_array_get kernel/trace/trace.c:451 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
1 lock held by syz.2.129/4851:
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: trace_array_get kernel/trace/trace.c:451 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
1 lock held by syz.4.144/4886:
 #0: ffffffff8d1615a8 (
trace_types_lock){+.+.}-{3:3}, at: trace_array_get kernel/trace/trace.c:451 [inline]
trace_types_lock){+.+.}-{3:3}, at: tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
trace_types_lock){+.+.}-{3:3}, at: show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
1 lock held by syz-executor/4887:
 #0: ffffffff8e24d5c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8e24d5c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x79f/0xf10 net/core/rtnetlink.c:5695
1 lock held by syz.1.141/4888:
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: trace_array_get kernel/trace/trace.c:451 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: tracing_check_open_get_tr kernel/trace/trace.c:501 [inline]
 #0: ffffffff8d1615a8 (trace_types_lock){+.+.}-{3:3}, at: show_traces_open+0x7c/0x270 kernel/trace/trace.c:5105
3 locks held by syz-executor/4892:
 #0: ffffffff8e24d5c8 (rtnl_mutex
){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x79f/0xf10 net/core/rtnetlink.c:5695
 #1: ffff88805926d3e8 (&wg->device_update_lock){+.+.}-{3:3}, at: wg_open+0x223/0x420 drivers/net/wireguard/device.c:49
 #2: ffffffff8d123a28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
 #2: ffffffff8d123a28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2d1/0x750 kernel/rcu/tree_exp.h:845
1 lock held by syz-executor/4946:
 #0: ffffffff8e24d5c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8e24d5c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x79f/0xf10 net/core/rtnetlink.c:5695
1 lock held by syz-executor/4948:
 #0: ffffffff8e24d5c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8e24d5c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x79f/0xf10 net/core/rtnetlink.c:5695

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

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
 watchdog+0xe1b/0xe60 kernel/hung_task.c:369
 kthread+0x42e/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4302 Comm: kworker/0:6 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: events hci_cmd_timeout
RIP: 0010:format_decode+0x146/0x1330 lib/vsprintf.c:2545
Code: 48 c1 e8 03 0f b6 04 18 84 c0 75 2b 45 0f b6 3e 4c 89 ff 48 c7 c6 40 fa 74 8d e8 65 bd 6c fd 45 85 ff 74 2d 41 83 ff 25 74 20 <e8> f5 b8 6c fd 49 ff c6 48 ff c5 eb c6 89 e9 80 e1 07 38 c1 7c cc
RSP: 0018:ffffc900030af450 EFLAGS: 00000202
RAX: 0000000000000002 RBX: dffffc0000000000 RCX: 0000000000000001
RDX: ffffffff840c6a5b RSI: ffffffff8d74fa40 RDI: 000000000000005d
RBP: ffffffff8a2be344 R08: ffff88802d439dc0 R09: 0000000000000002
R10: 0000000000000025 R11: 0000000000000000 R12: ffffffff8a2be344
R13: ffff0a0000000604 R14: ffffffff8a2be344 R15: 000000000000005d
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055557f736a38 CR3: 000000002bd78000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 vsnprintf+0xef/0x1c20 lib/vsprintf.c:2763
 sprintf+0xe4/0x140 lib/vsprintf.c:3013
 print_caller kernel/printk/printk.c:1285 [inline]
 info_print_prefix+0x20c/0x360 kernel/printk/printk.c:1302
 record_print_text kernel/printk/printk.c:1349 [inline]
 console_unlock+0x650/0x10f0 kernel/printk/printk.c:2725
 vprintk_emit+0xc0/0x150 kernel/printk/printk.c:2274
 _printk+0xda/0x130 kernel/printk/printk.c:2299
 bt_err+0x11e/0x180 net/bluetooth/lib.c:180
 hci_cmd_timeout+0x10a/0x220 net/bluetooth/hci_core.c:2797
 process_one_work+0x867/0xff0 kernel/workqueue.c:2310
 worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457
 kthread+0x42e/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/10/09 14:24 linux-5.15.y a051a4bf909f b2734a59 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in show_traces_open
2026/10/06 15:14 linux-5.15.y a051a4bf909f f7710056 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in show_traces_open
2026/10/09 10:22 linux-5.15.y a051a4bf909f b2734a59 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in show_traces_open
2026/10/06 06:55 linux-5.15.y a051a4bf909f f7710056 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in show_traces_open
* Struck through repros no longer work on HEAD.