[v5.15] INFO: task hung in _free_event
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syzbot
Nov 8, 2025, 11:01:30 PM (2 days ago) Nov 8
to syzkaller...@googlegroups.com
Hello,
syzbot found the following issue on:
HEAD commit: cc5ec8769306 Linux 5.15.196
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=10788412580000
kernel config: https://syzkaller.appspot.com/x/.config?x=e1bb6d24ef2164eb
dashboard link: https://syzkaller.appspot.com/bug?extid=196f888bfb53580e9f43
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/ed7568bc5bb4/disk-cc5ec876.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e343e0aaac77/vmlinux-cc5ec876.xz
kernel image: https://storage.googleapis.com/syzbot-assets/089870f2a980/bzImage-cc5ec876.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+196f88...@syzkaller.appspotmail.com
INFO: task syz.0.1070:8971 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1070 state:D stack:27648 pid: 8971 ppid: 8754 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 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+0xc71/0x2390 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239
_free_event+0x850/0xe60 kernel/events/core.c:5164
put_event kernel/events/core.c:5258 [inline]
perf_event_release_kernel+0x832/0x8c0 kernel/events/core.c:5383
perf_release+0x37/0x40 kernel/events/core.c:5393
__fput+0x234/0x930 fs/file_table.c:311
task_work_run+0x125/0x1a0 kernel/task_work.c:188
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fbf89dd06c9
RSP: 002b:00007ffc4d19f468 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 0000000000044c2b RCX: 00007fbf89dd06c9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fbf8a028da0 R08: 0000000000000001 R09: 0000001e4d19f75f
R10: 0000001b2ea20000 R11: 0000000000000246 R12: 00007fbf8a026fac
R13: 00007fbf8a026fa0 R14: ffffffffffffffff R15: 00007ffc4d19f580
</TASK>
INFO: task syz.2.1072:8976 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.1072 state:D stack:27488 pid: 8976 ppid: 8753 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 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+0xc71/0x2390 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239
_free_event+0x850/0xe60 kernel/events/core.c:5164
put_event kernel/events/core.c:5258 [inline]
perf_event_release_kernel+0x832/0x8c0 kernel/events/core.c:5383
perf_release+0x37/0x40 kernel/events/core.c:5393
__fput+0x234/0x930 fs/file_table.c:311
task_work_run+0x125/0x1a0 kernel/task_work.c:188
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fa9618376c9
RSP: 002b:00007fff1357a318 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007fa961a8fda0 RCX: 00007fa9618376c9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fa961a8fda0 R08: 000000000000012c R09: 000000111357a60f
R10: 00000000003ffcb0 R11: 0000000000000246 R12: 00000000000450e7
R13: 00007fa961a8e270 R14: ffffffffffffffff R15: 00007fff1357a430
</TASK>
INFO: task syz.5.1073:8985 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.1073 state:D stack:29088 pid: 8985 ppid: 8741 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 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+0xc71/0x2390 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
perf_uprobe_init+0x11f/0x190 kernel/trace/trace_event_perf.c:335
perf_uprobe_event_init+0xe2/0x170 kernel/events/core.c:10253
perf_try_init_event+0x12b/0x3d0 kernel/events/core.c:11601
perf_init_event kernel/events/core.c:11665 [inline]
perf_event_alloc+0xfcf/0x2240 kernel/events/core.c:11957
__do_sys_perf_event_open kernel/events/core.c:12495 [inline]
__se_sys_perf_event_open+0x6c5/0x1b80 kernel/events/core.c:12387
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: 0033:0x7fdbf8a5d6c9
RSP: 002b:00007fdbf6ca3038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007fdbf8cb4090 RCX: 00007fdbf8a5d6c9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000340
RBP: 00007fdbf8adff91 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007fdbf8cb4128 R14: 00007fdbf8cb4090 R15: 00007fffd231b0c8
</TASK>
INFO: task syz.5.1073:8986 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.1073 state:D stack:29088 pid: 8986 ppid: 8741 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 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+0xc71/0x2390 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
perf_trace_init+0x4c/0x2d0 kernel/trace/trace_event_perf.c:221
perf_tp_event_init+0x89/0x110 kernel/events/core.c:10102
perf_try_init_event+0x12b/0x3d0 kernel/events/core.c:11601
perf_init_event kernel/events/core.c:11665 [inline]
perf_event_alloc+0xfcf/0x2240 kernel/events/core.c:11957
__do_sys_perf_event_open kernel/events/core.c:12495 [inline]
__se_sys_perf_event_open+0x6c5/0x1b80 kernel/events/core.c:12387
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: 0033:0x7fdbf8a5d6c9
RSP: 002b:00007fdbf6c82038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007fdbf8cb4180 RCX: 00007fdbf8a5d6c9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000100
RBP: 00007fdbf8adff91 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007fdbf8cb4218 R14: 00007fdbf8cb4180 R15: 00007fffd231b0c8
</TASK>
Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8c11c760 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
1 lock held by klogd/3549:
1 lock held by udevd/3560:
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
2 locks held by getty/3950:
#0: ffff88802b996098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc900026562e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
4 locks held by kworker/0:47/7174:
#0: ffff8880b903a358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
#1: ffff8880b9027888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x4d6/0x810 kernel/sched/psi.c:891
#2: ffff8880b90280d8 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x123/0x270 kernel/time/timer.c:946
#3: ffffffff96327ed8 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x65/0x480 lib/debugobjects.c:694
2 locks held by dhcpcd-run-hook/8524:
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
#1: ffff88802b89b228 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#1: ffff88802b89b228 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:504 [inline]
#1: ffff88802b89b228 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1466 [inline]
#1: ffff88802b89b228 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x238/0x1380 kernel/fork.c:1518
1 lock held by syz-executor/8747:
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
1 lock held by syz-executor/8749:
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
1 lock held by syz.0.1070/8971:
#0: ffffffff8c169e68 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239
1 lock held by syz.2.1072/8976:
#0: ffffffff8c169e68 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239
4 locks held by syz.5.1073/8984:
#0: ffffffff96115918 (&pmus_srcu){....}-{0:0}, at: rcu_lock_acquire+0x9/0x30 include/linux/rcupdate.h:313
#1: ffffffff8c169e68 (event_mutex){+.+.}-{3:3}, at: perf_uprobe_init+0x11f/0x190 kernel/trace/trace_event_perf.c:335
#2: ffff8880600e7090 (&uprobe->register_rwsem){+.+.}-{3:3}, at: __uprobe_register+0x450/0x750 kernel/events/uprobes.c:1178
#3: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: register_for_each_vma+0x2f/0xbb0 kernel/events/uprobes.c:1041
2 locks held by syz.5.1073/8985:
#0: ffffffff96115918 (&pmus_srcu){....}-{0:0}, at: rcu_lock_acquire+0x9/0x30 include/linux/rcupdate.h:313
#1: ffffffff8c169e68 (event_mutex){+.+.}-{3:3}, at: perf_uprobe_init+0x11f/0x190 kernel/trace/trace_event_perf.c:335
2 locks held by syz.5.1073/8986:
#0: ffffffff96115918 (&pmus_srcu){....}-{0:0}, at: rcu_lock_acquire+0x9/0x30 include/linux/rcupdate.h:313
#1: ffffffff8c169e68 (event_mutex){+.+.}-{3:3}, at: perf_trace_init+0x4c/0x2d0 kernel/trace/trace_event_perf.c:221
1 lock held by syz-executor/8988:
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
1 lock held by syz-executor/8989:
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
1 lock held by syz-executor/8990:
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
1 lock held by syz-executor/8991:
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
1 lock held by syz-executor/8992:
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
<TASK>
dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x397/0x3d0 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+0xe0f/0xe50 kernel/hung_task.c:369
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4596 Comm: kworker/u4:7 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: bat_events batadv_nc_worker
RIP: 0010:lock_release+0x6/0x870 kernel/locking/lockdep.c:5631
Code: c1 03 38 c1 0f 8c c1 f8 ff ff 48 89 df e8 b2 b8 5f 00 e9 b4 f8 ff ff bb 2f 00 00 00 e9 ca f8 ff ff 0f 1f 00 55 48 89 e5 41 57 <41> 56 41 55 41 54 53 48 83 e4 e0 48 81 ec e0 00 00 00 48 89 74 24
RSP: 0018:ffffc900034afbc8 EFLAGS: 00000293
RAX: ffffffff897f17ea RBX: dffffc0000000000 RCX: ffff888017f91dc0
RDX: 0000000000000000 RSI: ffffffff897f17e5 RDI: ffffffff8c11c760
RBP: ffffc900034afbd0 R08: dffffc0000000000 R09: fffffbfff1ff7c19
R10: fffffbfff1ff7c19 R11: 1ffffffff1ff7c18 R12: 0000000000000359
R13: fffffffffffffe38 R14: ffff888046110c80 R15: ffff888065fe62d0
FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f684753c229 CR3: 000000002a29f000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
<TASK>
rcu_read_unlock include/linux/rcupdate.h:773 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:416 [inline]
batadv_nc_worker+0x25b/0x5c0 net/batman-adv/network-coding.c:723
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.
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If the report is already addressed, let syzbot know by replying with:
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#syz undup
syzbot found the following issue on:
HEAD commit: cc5ec8769306 Linux 5.15.196
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=10788412580000
kernel config: https://syzkaller.appspot.com/x/.config?x=e1bb6d24ef2164eb
dashboard link: https://syzkaller.appspot.com/bug?extid=196f888bfb53580e9f43
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/ed7568bc5bb4/disk-cc5ec876.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e343e0aaac77/vmlinux-cc5ec876.xz
kernel image: https://storage.googleapis.com/syzbot-assets/089870f2a980/bzImage-cc5ec876.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+196f88...@syzkaller.appspotmail.com
INFO: task syz.0.1070:8971 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1070 state:D stack:27648 pid: 8971 ppid: 8754 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 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+0xc71/0x2390 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239
_free_event+0x850/0xe60 kernel/events/core.c:5164
put_event kernel/events/core.c:5258 [inline]
perf_event_release_kernel+0x832/0x8c0 kernel/events/core.c:5383
perf_release+0x37/0x40 kernel/events/core.c:5393
__fput+0x234/0x930 fs/file_table.c:311
task_work_run+0x125/0x1a0 kernel/task_work.c:188
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fbf89dd06c9
RSP: 002b:00007ffc4d19f468 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 0000000000044c2b RCX: 00007fbf89dd06c9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fbf8a028da0 R08: 0000000000000001 R09: 0000001e4d19f75f
R10: 0000001b2ea20000 R11: 0000000000000246 R12: 00007fbf8a026fac
R13: 00007fbf8a026fa0 R14: ffffffffffffffff R15: 00007ffc4d19f580
</TASK>
INFO: task syz.2.1072:8976 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.1072 state:D stack:27488 pid: 8976 ppid: 8753 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 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+0xc71/0x2390 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239
_free_event+0x850/0xe60 kernel/events/core.c:5164
put_event kernel/events/core.c:5258 [inline]
perf_event_release_kernel+0x832/0x8c0 kernel/events/core.c:5383
perf_release+0x37/0x40 kernel/events/core.c:5393
__fput+0x234/0x930 fs/file_table.c:311
task_work_run+0x125/0x1a0 kernel/task_work.c:188
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fa9618376c9
RSP: 002b:00007fff1357a318 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007fa961a8fda0 RCX: 00007fa9618376c9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fa961a8fda0 R08: 000000000000012c R09: 000000111357a60f
R10: 00000000003ffcb0 R11: 0000000000000246 R12: 00000000000450e7
R13: 00007fa961a8e270 R14: ffffffffffffffff R15: 00007fff1357a430
</TASK>
INFO: task syz.5.1073:8985 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.1073 state:D stack:29088 pid: 8985 ppid: 8741 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 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+0xc71/0x2390 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
perf_uprobe_init+0x11f/0x190 kernel/trace/trace_event_perf.c:335
perf_uprobe_event_init+0xe2/0x170 kernel/events/core.c:10253
perf_try_init_event+0x12b/0x3d0 kernel/events/core.c:11601
perf_init_event kernel/events/core.c:11665 [inline]
perf_event_alloc+0xfcf/0x2240 kernel/events/core.c:11957
__do_sys_perf_event_open kernel/events/core.c:12495 [inline]
__se_sys_perf_event_open+0x6c5/0x1b80 kernel/events/core.c:12387
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: 0033:0x7fdbf8a5d6c9
RSP: 002b:00007fdbf6ca3038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007fdbf8cb4090 RCX: 00007fdbf8a5d6c9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000340
RBP: 00007fdbf8adff91 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007fdbf8cb4128 R14: 00007fdbf8cb4090 R15: 00007fffd231b0c8
</TASK>
INFO: task syz.5.1073:8986 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.1073 state:D stack:29088 pid: 8986 ppid: 8741 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 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+0xc71/0x2390 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
perf_trace_init+0x4c/0x2d0 kernel/trace/trace_event_perf.c:221
perf_tp_event_init+0x89/0x110 kernel/events/core.c:10102
perf_try_init_event+0x12b/0x3d0 kernel/events/core.c:11601
perf_init_event kernel/events/core.c:11665 [inline]
perf_event_alloc+0xfcf/0x2240 kernel/events/core.c:11957
__do_sys_perf_event_open kernel/events/core.c:12495 [inline]
__se_sys_perf_event_open+0x6c5/0x1b80 kernel/events/core.c:12387
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: 0033:0x7fdbf8a5d6c9
RSP: 002b:00007fdbf6c82038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007fdbf8cb4180 RCX: 00007fdbf8a5d6c9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000100
RBP: 00007fdbf8adff91 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007fdbf8cb4218 R14: 00007fdbf8cb4180 R15: 00007fffd231b0c8
</TASK>
Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8c11c760 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
1 lock held by klogd/3549:
1 lock held by udevd/3560:
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
2 locks held by getty/3950:
#0: ffff88802b996098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc900026562e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
4 locks held by kworker/0:47/7174:
#0: ffff8880b903a358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
#1: ffff8880b9027888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x4d6/0x810 kernel/sched/psi.c:891
#2: ffff8880b90280d8 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x123/0x270 kernel/time/timer.c:946
#3: ffffffff96327ed8 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x65/0x480 lib/debugobjects.c:694
2 locks held by dhcpcd-run-hook/8524:
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
#1: ffff88802b89b228 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#1: ffff88802b89b228 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:504 [inline]
#1: ffff88802b89b228 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1466 [inline]
#1: ffff88802b89b228 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x238/0x1380 kernel/fork.c:1518
1 lock held by syz-executor/8747:
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
1 lock held by syz-executor/8749:
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
1 lock held by syz.0.1070/8971:
#0: ffffffff8c169e68 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239
1 lock held by syz.2.1072/8976:
#0: ffffffff8c169e68 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239
4 locks held by syz.5.1073/8984:
#0: ffffffff96115918 (&pmus_srcu){....}-{0:0}, at: rcu_lock_acquire+0x9/0x30 include/linux/rcupdate.h:313
#1: ffffffff8c169e68 (event_mutex){+.+.}-{3:3}, at: perf_uprobe_init+0x11f/0x190 kernel/trace/trace_event_perf.c:335
#2: ffff8880600e7090 (&uprobe->register_rwsem){+.+.}-{3:3}, at: __uprobe_register+0x450/0x750 kernel/events/uprobes.c:1178
#3: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: register_for_each_vma+0x2f/0xbb0 kernel/events/uprobes.c:1041
2 locks held by syz.5.1073/8985:
#0: ffffffff96115918 (&pmus_srcu){....}-{0:0}, at: rcu_lock_acquire+0x9/0x30 include/linux/rcupdate.h:313
#1: ffffffff8c169e68 (event_mutex){+.+.}-{3:3}, at: perf_uprobe_init+0x11f/0x190 kernel/trace/trace_event_perf.c:335
2 locks held by syz.5.1073/8986:
#0: ffffffff96115918 (&pmus_srcu){....}-{0:0}, at: rcu_lock_acquire+0x9/0x30 include/linux/rcupdate.h:313
#1: ffffffff8c169e68 (event_mutex){+.+.}-{3:3}, at: perf_trace_init+0x4c/0x2d0 kernel/trace/trace_event_perf.c:221
1 lock held by syz-executor/8988:
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
1 lock held by syz-executor/8989:
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
1 lock held by syz-executor/8990:
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
1 lock held by syz-executor/8991:
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
1 lock held by syz-executor/8992:
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68f0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
<TASK>
dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x397/0x3d0 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+0xe0f/0xe50 kernel/hung_task.c:369
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4596 Comm: kworker/u4:7 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: bat_events batadv_nc_worker
RIP: 0010:lock_release+0x6/0x870 kernel/locking/lockdep.c:5631
Code: c1 03 38 c1 0f 8c c1 f8 ff ff 48 89 df e8 b2 b8 5f 00 e9 b4 f8 ff ff bb 2f 00 00 00 e9 ca f8 ff ff 0f 1f 00 55 48 89 e5 41 57 <41> 56 41 55 41 54 53 48 83 e4 e0 48 81 ec e0 00 00 00 48 89 74 24
RSP: 0018:ffffc900034afbc8 EFLAGS: 00000293
RAX: ffffffff897f17ea RBX: dffffc0000000000 RCX: ffff888017f91dc0
RDX: 0000000000000000 RSI: ffffffff897f17e5 RDI: ffffffff8c11c760
RBP: ffffc900034afbd0 R08: dffffc0000000000 R09: fffffbfff1ff7c19
R10: fffffbfff1ff7c19 R11: 1ffffffff1ff7c18 R12: 0000000000000359
R13: fffffffffffffe38 R14: ffff888046110c80 R15: ffff888065fe62d0
FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f684753c229 CR3: 000000002a29f000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
<TASK>
rcu_read_unlock include/linux/rcupdate.h:773 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:416 [inline]
batadv_nc_worker+0x25b/0x5c0 net/batman-adv/network-coding.c:723
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
---
This report is generated by a bot. It may contain errors.
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