INFO: task syz.9.3172:16821 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.9.3172 state:D stack:24000 pid:16821 ppid:12827 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
schedule+0xb9/0x180 kernel/sched/core.c:6637
perf_pending_task_sync kernel/events/core.c:5031 [inline]
_free_event+0x171/0x10a0 kernel/events/core.c:5037
put_event kernel/events/core.c:5162 [inline]
perf_event_release_kernel+0x832/0x8c0 kernel/events/core.c:5287
perf_release+0x37/0x40 kernel/events/core.c:5297
__fput+0x22c/0x920 fs/file_table.c:320
task_work_run+0x1ca/0x250 kernel/task_work.c:203
exit_task_work include/linux/task_work.h:39 [inline]
do_exit+0x93e/0x2400 kernel/exit.c:880
do_group_exit+0x217/0x2d0 kernel/exit.c:1022
get_signal+0x1272/0x1350 kernel/signal.c:2871
arch_do_signal_or_restart+0xb7/0x1240 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:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f803778f749
RSP: 002b:00007f80359d4fe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: fffffffffffffffc RBX: 00007f80379e6090 RCX: 00007f803778f749
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000126400
RBP: 00007f8037813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f80379e6128 R14: 00007f80379e6090 R15: 00007ffe3e274b88
Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8cb2b630 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
#0: ffffffff8cb2be50 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/27:
#0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513
2 locks held by getty/4025:
#0: ffff88807e3e8098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
#1: ffffc9000327e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41b/0x1380 drivers/tty/n_tty.c:2198
3 locks held by kworker/1:2/4365:
2 locks held by kworker/u4:14/5626:
#0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc9000c79fd00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
3 locks held by kworker/1:9/7067:
#0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc90003797d00 (set_printk_work){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#2: ffffffff8cb7fd28 (event_mutex){+.+.}-{3:3}, at: __ftrace_set_clr_event kernel/trace/trace_events.c:1217 [inline]
#2: ffffffff8cb7fd28 (event_mutex){+.+.}-{3:3}, at: trace_set_clr_event+0xbe/0x130 kernel/trace/trace_events.c:1283
3 locks held by kworker/1:5/13373:
#0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc9000dc5fd00 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#2: ffffffff8cb30978 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
#2: ffffffff8cb30978 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x455/0x830 kernel/rcu/tree_exp.h:962
2 locks held by kworker/1:8/13374:
#0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc9000e89fd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
2 locks held by kworker/u4:37/16240:
#0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc9000c7afd00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
2 locks held by kworker/u4:52/16256:
#0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
#1: ffffc9000c87fd00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267
3 locks held by syz.3.4067/20126:
1 lock held by syz.1.4081/20167:
#0: ffffffff8cb7fd28 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239
2 locks held by syz.1.4081/20168:
#0: ffffffff8dd43c08 (bpf_dispatcher_xdp.mutex){+.+.}-{3:3}, at: bpf_dispatcher_change_prog+0x9d/0xcc0 kernel/bpf/dispatcher.c:146
#1: ffffffff8cb30978 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline]
#1: ffffffff8cb30978 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x346/0x830 kernel/rcu/tree_exp.h:962
7 locks held by syz.0.4086/20186:
#0: ffff88807b49ed68 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2ae/0x360 fs/file.c:1038
#1: ffff8880731c6460 (sb_writers#10){.+.+}-{0:0}, at: vfs_write+0x256/0x960 fs/read_write.c:580
#2: ffff888076bf4488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e3/0x520 fs/kernfs/file.c:343
#3: ffffffff8cb536e8 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_lock include/linux/cgroup.h:442 [inline]
#3: ffffffff8cb536e8 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_kn_lock_live+0xee/0x230 kernel/cgroup/cgroup.c:1700
#4: ffffffff8c9c7b30 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2476 [inline]
#4: ffffffff8c9c7b30 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_procs_write_start+0x183/0x600 kernel/cgroup/cgroup.c:2982
#5: ffffffff8cb538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2478 [inline]
#5: ffffffff8cb538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_procs_write_start+0x199/0x600 kernel/cgroup/cgroup.c:2982
#6: ffffffff8cb30978 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline]
#6: ffffffff8cb30978 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x346/0x830 kernel/rcu/tree_exp.h:962
4 locks held by syz.0.4086/20187:
#0: ffff888042e15268 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2ae/0x360 fs/file.c:1038
#1: ffff8880731c6460 (sb_writers#10){.+.+}-{0:0}, at: vfs_write+0x256/0x960 fs/read_write.c:580
#2: ffff888023863888 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e3/0x520 fs/kernfs/file.c:343
#3: ffffffff8cb536e8 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_lock include/linux/cgroup.h:442 [inline]
#3: ffffffff8cb536e8 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_kn_lock_live+0xee/0x230 kernel/cgroup/cgroup.c:1700
2 locks held by syz.3.4088/20192:
#0: ffffffff96c3a168 (&pmus_srcu){....}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff96c3a168 (&pmus_srcu){....}-{0:0}, at: srcu_read_lock include/linux/srcu.h:165 [inline]
#0: ffffffff96c3a168 (&pmus_srcu){....}-{0:0}, at: perf_init_event kernel/events/core.c:11624 [inline]
#0: ffffffff96c3a168 (&pmus_srcu){....}-{0:0}, at: perf_event_alloc+0xbe2/0x21b0 kernel/events/core.c:11950
#1: ffffffff8cb7fd28 (event_mutex){+.+.}-{3:3}, at: perf_trace_init+0x4c/0x2d0 kernel/trace/trace_event_perf.c:221
2 locks held by syz.3.4088/20194:
#0: ffffffff96c3a168 (&pmus_srcu){....}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff96c3a168 (&pmus_srcu){....}-{0:0}, at: srcu_read_lock include/linux/srcu.h:165 [inline]
#0: ffffffff96c3a168 (&pmus_srcu){....}-{0:0}, at: perf_init_event kernel/events/core.c:11624 [inline]
#0: ffffffff96c3a168 (&pmus_srcu){....}-{0:0}, at: perf_event_alloc+0xbe2/0x21b0 kernel/events/core.c:11950
#1: ffffffff8cb7fd28 (event_mutex){+.+.}-{3:3}, at: perf_trace_init+0x4c/0x2d0 kernel/trace/trace_event_perf.c:221
1 lock held by syz.3.4088/20196:
#0: ffffffff8cb71ec8 (tracepoints_mutex){+.+.}-{3:3}, at: tracepoint_probe_register_prio_may_exist+0x40/0x90 kernel/tracepoint.c:478
=============================================
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:
dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106
nmi_cpu_backtrace+0x3f4/0x470 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+0xeee/0xf30 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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 20126 Comm: syz.3.4067 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4737 [inline]
RIP: 0010:__lock_acquire+0x6ce/0x7c50 kernel/locking/lockdep.c:4999
Code: 24 d8 0a 00 00 41 8d 47 ff 83 f8 ff 4c 89 e1 41 bc ff ff ff ff 44 0f 4c e0 4c 8d a9 00 0b 00 00 41 ff c4 45 8d 77 01 49 ff cf <44> 89 f0 83 c0 fe 0f 88 70 01 00 00 44 89 fb 81 e3 ff ff ff 7f 83
RSP: 0018:ffffc9000db2ee80 EFLAGS: 00000046
RAX: ffff88802d006468 RBX: 0000000000010001 RCX: ffff88802d005940
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90ae22e0
RBP: ffffc9000db2f0d0 R08: dffffc0000000000 R09: fffffbfff215c45d
R10: fffffbfff215c45d R11: 1ffffffff215c45c R12: 0000000000000000
R13: ffff88802d006440 R14: 0000000000000001 R15: ffffffffffffffff
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0bf69b7198 CR3: 000000003bb68000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662
down_write+0x36/0x60 kernel/locking/rwsem.c:1573
inode_lock include/linux/fs.h:758 [inline]
generic_file_write_iter+0x7f/0x2e0 mm/filemap.c:4003
__kernel_write_iter+0x26d/0x630 fs/read_write.c:517
dump_emit_page fs/coredump.c:950 [inline]
dump_user_range+0x3ea/0x7f0 fs/coredump.c:977
elf_core_dump+0x2f77/0x3490 fs/binfmt_elf.c:2354
do_coredump+0x15ff/0x22b0 fs/coredump.c:824
get_signal+0x10aa/0x1350 kernel/signal.c:2857
arch_do_signal_or_restart+0xb7/0x1240 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
irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:316
exc_page_fault+0x88/0x100 arch/x86/mm/fault.c:1490
asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0033:0x7ff2b384f6b7
Code: 88 15 42 60 ec 00 88 05 3f 60 ec 00 c3 50 48 8d 35 e9 48 1c 00 48 8d 3d ef 48 1c 00 31 c0 e8 20 f7 ff ff 53 89 fb 48 83 ec 10 <64> 8b 04 25 94 ff ff ff 85 c0 74 2a 89 fe 31 c0 bf 3c 00 00 00 e8
RSP: 002b:00007ff2b47d8120 EFLAGS: 00010202
RAX: 0000000000000000 RBX: 000000000000000b RCX: 00007ff2b398f749
RDX: 00007ff2b47d8140 RSI: 00007ff2b47d8270 RDI: 000000000000000b
RBP: 00007ff2b3a13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007ff2b3be6038 R14: 00007ff2b3be5fa0 R15: 00007ffc19458d48