INFO: task syz.0.503:4847 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.503       state:D stack:27648 pid: 4847 ppid:  4310 flags:0x00004002
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
 perf_pending_task_sync+0x13c/0x1c0 kernel/events/core.c:5127
 _free_event+0x34/0xe60 kernel/events/core.c:5133
 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
 exit_task_work include/linux/task_work.h:33 [inline]
 do_exit+0x61e/0x20a0 kernel/exit.c:883
 do_group_exit+0x12e/0x300 kernel/exit.c:997
 __do_sys_exit_group kernel/exit.c:1008 [inline]
 __se_sys_exit_group kernel/exit.c:1006 [inline]
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1006
 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: 0033:0x7fc81dd6dec9
RSP: 002b:00007ffe1741c588 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fc81dd6dec9
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffe1741c5ec R08: 000000091741c67f R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 00000000000001e6
R13: 00000000000927c0 R14: 0000000000028688 R15: 00007ffe1741c640
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8c11c660 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by getty/3950:
 #0: ffff88814cf68098 (&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

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

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 08/18/2025
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: 3855 Comm: dhcpcd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:mark_lock+0x1/0x320 kernel/locking/lockdep.c:4552
Code: c1 7c 90 48 c7 c7 48 c9 69 8d e8 9a 83 5f 00 4c 89 f7 41 89 d9 e9 79 ff ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 <41> 57 41 56 41 55 41 54 53 50 89 d5 49 89 f6 48 89 fb 49 bd 00 00
RSP: 0018:ffffc900033af4f0 EFLAGS: 00000046
RAX: 0000000000000003 RBX: 0000000000000003 RCX: 0000000000000003
RDX: 0000000000000008 RSI: ffff88802897c6e8 RDI: ffff88802897bb80
RBP: ffffc900033af750 R08: dffffc0000000000 R09: fffffbfff1ff7a2f
R10: fffffbfff1ff7a2f R11: 1ffffffff1ff7a2e R12: ffff88802897c708
R13: ffff88802897bb80 R14: ffffffff8f988b38 R15: ffff88802897c6e8
FS:  00007f076ee66740(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000560224c7fa38 CR3: 000000001ed2a000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 mark_usage kernel/locking/lockdep.c:4512 [inline]
 __lock_acquire+0xd5a/0x7c60 kernel/locking/lockdep.c:4966
 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
 rcu_lock_acquire+0x20/0x30 include/linux/rcupdate.h:312
 rcu_read_lock include/linux/rcupdate.h:739 [inline]
 get_obj_cgroup_from_current+0xd1/0x2f0 mm/memcontrol.c:2922
 memcg_slab_pre_alloc_hook mm/slab.h:283 [inline]
 slab_pre_alloc_hook+0x7e/0xc0 mm/slab.h:497
 slab_alloc_node mm/slub.c:3139 [inline]
 slab_alloc mm/slub.c:3233 [inline]
 kmem_cache_alloc+0x3d/0x290 mm/slub.c:3238
 vm_area_dup kernel/fork.c:358 [inline]
 dup_mmap kernel/fork.c:557 [inline]
 dup_mm kernel/fork.c:1466 [inline]
 copy_mm+0x8b1/0x1380 kernel/fork.c:1518
 copy_process+0x17c6/0x3e00 kernel/fork.c:2290
 kernel_clone+0x219/0x930 kernel/fork.c:2679
 __do_sys_clone kernel/fork.c:2796 [inline]
 __se_sys_clone kernel/fork.c:2780 [inline]
 __x64_sys_clone+0x170/0x1c0 kernel/fork.c:2780
 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: 0033:0x7f076ef3a636
Code: 89 df e8 6d e8 f6 ff 45 31 c0 31 d2 31 f6 64 48 8b 04 25 10 00 00 00 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 52 89 c5 85 c0 75 31 64 48 8b 04 25 10 00 00
RSP: 002b:00007ffd0e2d1190 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffd0e2d1198 RCX: 00007f076ef3a636
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007ffd0e2f16e0 R08: 0000000000000000 R09: 0000000000000001
R10: 00007f076ee66a10 R11: 0000000000000246 R12: 00007ffd0e2d12d0
R13: 0000000000000000 R14: 0000000000000000 R15: 0000558f19ecbac0
 </TASK>