INFO: task syz.2.11652:10824 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.11652 state:D stack:24400 pid:10824 ppid:2717 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5246 [inline]
__schedule+0x107f/0x4030 kernel/sched/core.c:6563
schedule+0xb9/0x180 kernel/sched/core.c:6639
perf_pending_task_sync kernel/events/core.c:5031 [inline]
_free_event+0x176/0x1050 kernel/events/core.c:5037
put_event kernel/events/core.c:5162 [inline]
perf_event_release_kernel+0x7c4/0x850 kernel/events/core.c:5287
perf_release+0x37/0x40 kernel/events/core.c:5297
__fput+0x20a/0x8b0 fs/file_table.c:320
task_work_run+0x1d0/0x260 kernel/task_work.c:203
exit_task_work include/linux/task_work.h:39 [inline]
do_exit+0x9d5/0x2570 kernel/exit.c:881
do_group_exit+0x229/0x2e0 kernel/exit.c:1024
get_signal+0x1259/0x1340 kernel/signal.c:2872
arch_do_signal_or_restart+0xc4/0x1310 arch/x86/kernel/signal.c:871
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f361459de99
RSP: 002b:00007f3615454028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: 000000000000005c RBX: 00007f3614825fa0 RCX: 00007f361459de99
RDX: 0000000000044010 RSI: 0000200000000180 RDI: 000000000000000c
RBP: 00007f3614633eaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3614826038 R14: 00007f3614825fa0 R15: 00007ffcce349188
Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8cb2e4f0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
#0: ffffffff8cb2ed10 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
#0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6527
1 lock held by klogd/3629:
2 locks held by getty/4033:
#0: ffff88814cba2098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
#1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41e/0x1360 drivers/tty/n_tty.c:2198
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
watchdog+0xf0e/0xf50 kernel/hung_task.c:377
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 3629 Comm: klogd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
RIP: 0010:perf_trace_lock+0x33f/0x390 include/trace/events/lock.h:50
Code: 40 0e 36 e0 45 4b c7 44 3d 00 00 00 00 00 43 c7 44 3d 08 00 00 00 00 65 48 8b 04 25 28 00 00 00 48 3b 84 24 a0 00 00 00 75 23 <48> 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 48 c7 c7 00 a2 9f 8c
RSP: 0018:ffffc900032a7360 EFLAGS: 00000046
RAX: c7440e72833fd200 RBX: ffffe8ffffc36ed0 RCX: c7440e72833fd200
RDX: ffffffff841a46b1 RSI: ffffffff8adf5dc0 RDI: ffffffff8adf5d80
RBP: ffffc900032a7450 R08: ffffffff8e210aef R09: 1ffffffff1c4215d
R10: dffffc0000000000 R11: fffffbfff1c4215e R12: ffffe8ffffc36ed0
R13: 1ffff92000654e74 R14: ffffffff8c9f9b20 R15: dffffc0000000000
FS: 00007fcfbace1c80(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555980596660 CR3: 000000007e604000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000b6e DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
trace_lock_release include/trace/events/lock.h:69 [inline]
lock_release+0x8ad/0x920 kernel/locking/lockdep.c:5687
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline]
_raw_spin_unlock_irqrestore+0x6d/0x120 kernel/locking/spinlock.c:194
__debug_check_no_obj_freed lib/debugobjects.c:1054 [inline]
debug_check_no_obj_freed+0x471/0x520 lib/debugobjects.c:1075
free_pages_prepare mm/page_alloc.c:1493 [inline]
free_pcp_prepare mm/page_alloc.c:1537 [inline]
free_unref_page_prepare+0x2c3/0x9e0 mm/page_alloc.c:3414
free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3509
qlink_free mm/kasan/quarantine.c:168 [inline]
qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294
__kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:306
kasan_slab_alloc include/linux/kasan.h:201 [inline]
slab_post_alloc_hook+0x4b/0x490 mm/slab.h:737
slab_alloc_node mm/slub.c:3359 [inline]
kmem_cache_alloc_node+0x1ad/0x310 mm/slub.c:3404
__alloc_skb+0xf9/0x7d0 net/core/skbuff.c:505
alloc_skb include/linux/skbuff.h:1303 [inline]
alloc_skb_with_frags+0xa7/0x710 net/core/skbuff.c:6186
sock_alloc_send_pskb+0x87f/0x9a0 net/core/sock.c:2764
unix_dgram_sendmsg+0x5c1/0x16f0 net/unix/af_unix.c:1945
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg net/socket.c:730 [inline]
__sys_sendto+0x497/0x650 net/socket.c:2153
__do_sys_sendto net/socket.c:2165 [inline]
__se_sys_sendto net/socket.c:2161 [inline]
__x64_sys_sendto+0xda/0xf0 net/socket.c:2161
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fcfbae31407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffef8c63e70 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fcfbace1c80 RCX: 00007fcfbae31407
RDX: 000000000000003a RSI: 00007ffef8c63fb0 RDI: 0000000000000003
RBP: 00007ffef8c643e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000004000 R11: 0000000000000202 R12: 00007ffef8c643f8
R13: 00007ffef8c63fb0 R14: 000000000000001f R15: 00007ffef8c63fb0