INFO: task syz.2.7367:28493 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.7367 state:D stack:21744 pid:28493 ppid:24884 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 schedule+0xb9/0x180 kernel/sched/core.c:6638 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+0x83e/0x8d0 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+0x1d0/0x260 kernel/task_work.c:203 exit_task_work include/linux/task_work.h:39 [inline] do_exit+0x982/0x2480 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+0xc4/0x1350 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: 0033:0x7f5f2f39c819 RSP: 002b:00007f5f301bbfd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: fffffffffffffff4 RBX: 00007f5f2f615fa0 RCX: 00007f5f2f39c819 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000ae12e400 RBP: 00007f5f2f432c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f5f2f616038 R14: 00007f5f2f615fa0 R15: 00007ffe3e727018 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8cb2df30 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 2 locks held by rcu_tasks_trace/13: #0: ffffffff8cb2e750 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 #1: ffffffff8cb33278 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #1: ffffffff8cb33278 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3c0/0x890 kernel/rcu/tree_exp.h:962 1 lock held by khungtaskd/28: #0: ffffffff8cb2d5a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8cb2d5a0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8cb2d5a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513 2 locks held by getty/4027: #0: ffff88814d2ec098 (&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+0x429/0x1390 drivers/tty/n_tty.c:2198 2 locks held by kworker/u4:27/9566: 3 locks held by kworker/u4:9/22668: #0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 #1: ffffc90003b37d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 #2: ffffffff8dd47de8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:263 3 locks held by kworker/u4:14/22679: #0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 #1: ffffc90003bb7d00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 #2: ffffffff8cb33278 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #2: ffffffff8cb33278 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2ec/0x890 kernel/rcu/tree_exp.h:962 3 locks held by kworker/u4:21/22694: #0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 #1: ffffc90003c8fd00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 #2: ffffffff8dd47de8 (rtnl_mutex){+.+.}-{3:3}, at: bpf_map_offload_map_free+0x10/0x80 kernel/bpf/offload.c:421 2 locks held by kworker/0:5/26221: #0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 #1: ffffc90003ca7d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 4 locks held by kworker/u4:0/30838: #0: ffff888017616938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 #1: ffffc900039ffd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 #2: ffffffff8dd3af10 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x148/0xba0 net/core/net_namespace.c:594 #3: ffffffff8dd47de8 (rtnl_mutex){+.+.}-{3:3}, at: wg_netns_pre_exit+0x18/0x1c0 drivers/net/wireguard/device.c:420 2 locks held by syz.5.8001/30854: 2 locks held by syz.4.8036/30956: 1 lock held by syz.1.8059/31011: #0: ffffffff8cb8c208 (bpf_event_mutex){+.+.}-{3:3}, at: perf_event_detach_bpf_prog+0x87/0x310 kernel/trace/bpf_trace.c:2178 2 locks held by syz.1.8059/31012: #0: ffffffff8dd3af10 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x32e/0x5b0 net/core/net_namespace.c:504 #1: ffffffff8dd47de8 (rtnl_mutex){+.+.}-{3:3}, at: register_nexthop_notifier+0x84/0x240 net/ipv4/nexthop.c:3619 1 lock held by syz.3.8060/31013: #0: ffffffff8cb8c208 (bpf_event_mutex){+.+.}-{3:3}, at: perf_event_detach_bpf_prog+0x87/0x310 kernel/trace/bpf_trace.c:2178 1 lock held by syz.0.8062/31021: #0: ffffffff8dd47de8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8dd47de8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x824/0xfc0 net/core/rtnetlink.c:6154 3 locks held by syz.5.8061/31025: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 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+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: 30915 Comm: syz.3.8025 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:-1 [inline] RIP: 0010:debug_check_no_obj_freed+0x1e2/0x530 lib/debugobjects.c:1009 Code: 0f 84 3a 03 00 00 49 89 ee 49 c1 ee 03 41 80 3c 16 00 74 12 48 89 ef e8 7c b0 bd fd 48 ba 00 00 00 00 00 fc ff df 48 8b 45 00 <48> 89 04 24 4c 8d 7d 18 4c 89 f8 48 c1 e8 03 80 3c 10 00 74 12 4c RSP: 0018:ffffc90003c17050 EFLAGS: 00000046 RAX: ffff888056c4d3b8 RBX: 0000000000000003 RCX: 0000000000000001 RDX: dffffc0000000000 RSI: 0000000000000004 RDI: ffffc90003c16f40 RBP: ffff8880566d3ce8 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff52000782de8 R12: ffff88803dd51000 R13: ffff88803dd50000 R14: 1ffff1100acda79d R15: ffff888058cbf298 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005555665814e8 CR3: 000000000c88e000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: free_pages_prepare mm/page_alloc.c:1492 [inline] free_pcp_prepare mm/page_alloc.c:1536 [inline] free_unref_page_prepare+0x2a6/0x9a0 mm/page_alloc.c:3413 free_unref_page_list+0xbb/0x8e0 mm/page_alloc.c:3554 release_pages+0x1fa6/0x2220 mm/swap.c:1035 __pagevec_release+0x6d/0xe0 mm/swap.c:1055 pagevec_release include/linux/pagevec.h:71 [inline] folio_batch_release include/linux/pagevec.h:135 [inline] shmem_undo_range+0x7c2/0x20c0 mm/shmem.c:946 shmem_truncate_range mm/shmem.c:1062 [inline] shmem_evict_inode+0x25b/0xa80 mm/shmem.c:1171 evict+0x4c9/0x8d0 fs/inode.c:705 __dentry_kill+0x431/0x650 fs/dcache.c:611 dentry_kill+0xb8/0x290 fs/dcache.c:-1 dput+0xfa/0x1d0 fs/dcache.c:918 __fput+0x5e0/0x920 fs/file_table.c:328 task_work_run+0x1d0/0x260 kernel/task_work.c:203 exit_task_work include/linux/task_work.h:39 [inline] do_exit+0x982/0x2480 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+0xc4/0x1350 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:1485 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7f64ce59c821 Code: Unable to access opcode bytes at 0x7f64ce59c7f7. RSP: 002b:fffffffffffffc70 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f64ce816090 RCX: 00007f64ce59c819 RDX: 0000000000000000 RSI: fffffffffffffc70 RDI: 0000000001022000 RBP: 00007f64ce632c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f64ce816128 R14: 00007f64ce816090 R15: 00007ffd4c600968