INFO: task syz.3.1430:9873 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.1430 state:D stack:23424 pid:9873 ppid:4265 flags:0x00004006 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 get_signal+0x11a6/0x1350 kernel/signal.c:2648 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: 0033:0x7fc02778f6c9 RSP: 002b:00007fc02853efe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: fffffffffffffffc RBX: 00007fc0279e6090 RCX: 00007fc02778f6c9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000 RBP: 00007fc027811f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007fc0279e6128 R14: 00007fc0279e6090 R15: 00007fffd8ebdd48 Showing all locks held in the system: 1 lock held by kworker/u4:1/11: #0: ffff8880b8e3aad8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537 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 2 locks held by kworker/0:1/14: #0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #1: ffffc90000137d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 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/4026: #0: ffff88802fb14098 (&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+0x41b/0x1380 drivers/tty/n_tty.c:2198 3 locks held by kworker/0:4/4325: #0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #1: ffffc900044a7d00 (fqdir_free_work){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #2: ffffffff8cb30840 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x48/0x600 kernel/rcu/tree.c:4023 4 locks held by kworker/u4:7/4359: #0: ffff888017616938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #1: ffffc900046bfd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #2: ffffffff8dd34a10 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x132/0xb80 net/core/net_namespace.c:594 #3: ffffffff8dd416e8 (rtnl_mutex){+.+.}-{3:3}, at: tc_action_net_exit include/net/act_api.h:171 [inline] #3: ffffffff8dd416e8 (rtnl_mutex){+.+.}-{3:3}, at: gate_exit_net+0x2c/0x100 net/sched/act_gate.c:654 2 locks held by kworker/u4:8/4420: 1 lock held by syz.3.1762/11339: #0: ffffffff8dd416e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8dd416e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3d/0x1b0 drivers/net/tun.c:3492 1 lock held by syz.8.1764/11349: #0: ffffffff8dd416e8 (rtnl_mutex){+.+.}-{3:3}, at: bpf_xdp_link_attach+0xc8/0x460 net/core/dev.c:9521 2 locks held by syz.8.1764/11356: #0: ffffffff8dd34a10 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x32e/0x5b0 net/core/net_namespace.c:504 #1: ffffffff8dd416e8 (rtnl_mutex){+.+.}-{3:3}, at: register_nexthop_notifier+0x7d/0x210 net/ipv4/nexthop.c:3613 1 lock held by syz.5.1765/11350: #0: ffffffff8dd416e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8dd416e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3d/0x1b0 drivers/net/tun.c:3492 1 lock held by syz.7.1766/11355: #0: ffffffff8dd416e8 (rtnl_mutex){+.+.}-{3:3}, at: dev_ioctl+0x601/0xea0 net/core/dev_ioctl.c:612 1 lock held by syz.7.1766/11357: #0: ffffffff8dd416e8 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x288/0x1af0 net/ipv4/devinet.c:1080 2 locks held by syz.6.1767/11353: #0: ffff88804d19c410 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #0: ffff88804d19c410 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: __sock_release net/socket.c:653 [inline] #0: ffff88804d19c410 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1400 #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 ============================================= 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 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 11 Comm: kworker/u4:1 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:memory_is_nonzero mm/kasan/generic.c:101 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline] RIP: 0010:kasan_check_range+0x62/0x290 mm/kasan/generic.c:189 Code: ff df 49 89 fb 49 c1 eb 03 49 b8 00 00 00 00 00 fc ff df 4f 8d 0c 03 48 8d 5c 37 ff 48 c1 eb 03 4e 8d 14 3b 4d 89 d6 4d 29 ce <49> 83 fe 10 7f 26 4d 85 f6 0f 84 39 01 00 00 48 f7 d3 4c 01 db 41 RSP: 0018:ffffc90000107928 EFLAGS: 00000002 RAX: 0000000000000001 RBX: 1ffffffff1c3ed55 RCX: ffffffff8187361d RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8e1f6aa8 RBP: ffffc90000107a10 R08: dffffc0000000000 R09: fffffbfff1c3ed55 R10: fffffbfff1c3ed56 R11: 1ffffffff1c3ed55 R12: dffffc0000000000 R13: 0000000000000000 R14: 0000000000000001 R15: dffffc0000000001 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c342033 CR3: 000000007f95e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: instrument_atomic_read include/linux/instrumented.h:72 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] cpumask_test_cpu include/linux/cpumask.h:444 [inline] cpu_online include/linux/cpumask.h:1030 [inline] trace_irq_disable_rcuidle+0x6d/0x140 include/trace/events/preemptirq.h:36 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline] _raw_spin_lock_irqsave+0x7f/0xf0 kernel/locking/spinlock.c:162 __debug_check_no_obj_freed lib/debugobjects.c:968 [inline] debug_check_no_obj_freed+0x136/0x530 lib/debugobjects.c:1009 slab_free_hook mm/slub.c:1704 [inline] slab_free_freelist_hook+0xd2/0x1a0 mm/slub.c:1755 slab_free mm/slub.c:3687 [inline] kmem_cache_free+0xf7/0x290 mm/slub.c:3709 nsim_dev_trap_report drivers/net/netdevsim/dev.c:821 [inline] nsim_dev_trap_report_work+0x76b/0xaf0 drivers/net/netdevsim/dev.c:851 process_one_work+0x898/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295