INFO: task syz.3.329:5280 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.329 state:D stack:23552 pid:5280 ppid:4271 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+0xb0/0x1230 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 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: 0033:0x7f55e1b8ebe9 RSP: 002b:00007f55e2a6efe8 EFLAGS: 00000202 ORIG_RAX: 0000000000000038 RAX: fffffffffffffff4 RBX: 00007f55e1dc5fa0 RCX: 00007f55e1b8ebe9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000430010e0 RBP: 00007f55e1c11e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000 R13: 00007f55e1dc6038 R14: 00007f55e1dc5fa0 R15: 00007fffd1051ed8 Showing all locks held in the system: 2 locks held by kworker/u4:0/9: #0: ffff8880b8f3aa98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537 #1: ffffffff8cb2a9e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #1: ffffffff8cb2a9e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #1: ffffffff8cb2a9e0 (rcu_read_lock){....}-{1:2}, at: do_perf_sw_event kernel/events/core.c:9706 [inline] #1: ffffffff8cb2a9e0 (rcu_read_lock){....}-{1:2}, at: ___perf_sw_event+0x13c/0x630 kernel/events/core.c:9744 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8cb2b370 (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: ffffffff8cb2bb90 (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: ffffffff8cb2a9e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8cb2a9e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8cb2a9e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513 2 locks held by getty/4028: #0: ffff88814cadc098 (&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 2 locks held by kworker/1:8/4398: #0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #1: ffffc90004b8fd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 2 locks held by syz.4.1332/8093: #0: ffffffff8cb7f968 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239 #1: ffffffff8cb306b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #1: ffffffff8cb306b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x346/0x830 kernel/rcu/tree_exp.h:962 1 lock held by syz.2.1335/8100: #0: ffffffff8cb7f968 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239 6 locks held by syz.2.1335/8108: 1 lock held by syz.0.1336/8101: #0: ffffffff8cb7f968 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239 1 lock held by syz.0.1336/8104: #0: ffffffff8dd44408 (bpf_dispatcher_xdp.mutex){+.+.}-{3:3}, at: bpf_dispatcher_change_prog+0x9d/0xcc0 kernel/bpf/dispatcher.c:146 1 lock held by syz.1.1338/8105: #0: ffffffff8cb7f968 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239 ============================================= 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 07/12/2025 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: 8108 Comm: syz.2.1335 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:fib6_check_expired include/net/ip6_fib.h:268 [inline] RIP: 0010:__find_rr_leaf+0x15e/0x6c0 net/ipv6/route.c:846 Code: e8 47 e8 9f f8 44 39 e3 0f 85 07 04 00 00 e8 d9 e6 9f f8 eb 05 e8 d2 e6 9f f8 49 8d 5e 54 49 89 dc 49 c1 ec 03 43 0f b6 04 2c <84> c0 0f 85 23 03 00 00 48 89 5c 24 78 8b 1b 89 de 81 e6 00 00 40 RSP: 0018:ffffc90003ebe4a0 EFLAGS: 00000a03 RAX: 0000000000000000 RBX: ffff8880586b3454 RCX: 0000000000080000 RDX: ffffc9000f1d2000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: ffffc90003ebe5f8 R08: ffffc90003ebe720 R09: ffffc90003ebe730 R10: fffff520007d7cb2 R11: 1ffff920007d7cb0 R12: 1ffff1100b0d668a R13: dffffc0000000000 R14: ffff8880586b3400 R15: ffffc90003ebe6f8 FS: 00007f9c062496c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2f711ff8 CR3: 0000000075215000 CR4: 00000000003506e0 DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: find_rr_leaf net/ipv6/route.c:893 [inline] rt6_select net/ipv6/route.c:937 [inline] fib6_table_lookup+0x39c/0xa70 net/ipv6/route.c:2223 ip6_pol_route+0x238/0x1260 net/ipv6/route.c:2259 pol_lookup_func include/net/ip6_fib.h:579 [inline] fib6_rule_lookup+0x2fc/0x570 net/ipv6/fib6_rules.c:121 ip6_route_output_flags+0xe3/0x330 net/ipv6/route.c:2679 ip6_dst_lookup_tail+0x262/0x1480 net/ipv6/ip6_output.c:1152 icmpv6_route_lookup+0xc8/0x530 net/ipv6/icmp.c:366 icmp6_send+0xf4c/0x18d0 net/ipv6/icmp.c:603 __icmpv6_send include/linux/icmpv6.h:28 [inline] icmpv6_send include/linux/icmpv6.h:49 [inline] gre_rcv+0xb4b/0x1100 net/ipv6/ip6_gre.c:622 ip6_protocol_deliver_rcu+0xb5e/0x13b0 net/ipv6/ip6_input.c:438 ip6_input_finish+0x181/0x2c0 net/ipv6/ip6_input.c:483 NF_HOOK+0x2ff/0x390 include/linux/netfilter.h:302 dst_input include/net/dst.h:463 [inline] ip6_sublist_rcv_finish net/ipv6/ip6_input.c:88 [inline] ip6_list_rcv_finish net/ipv6/ip6_input.c:146 [inline] ip6_sublist_rcv+0xed1/0x11c0 net/ipv6/ip6_input.c:320 ipv6_list_rcv+0x3e2/0x430 net/ipv6/ip6_input.c:355 __netif_receive_skb_list_ptype net/core/dev.c:5624 [inline] __netif_receive_skb_list_core+0x574/0x740 net/core/dev.c:5672 __netif_receive_skb_list net/core/dev.c:5724 [inline] netif_receive_skb_list_internal+0x90f/0xc50 net/core/dev.c:5815 netif_receive_skb_list+0x51/0x4e0 net/core/dev.c:5867 xdp_recv_frames net/bpf/test_run.c:256 [inline] xdp_test_run_batch net/bpf/test_run.c:334 [inline] bpf_test_run_xdp_live+0x16bc/0x1970 net/bpf/test_run.c:362 bpf_prog_test_run_xdp+0x6f1/0xe50 net/bpf/test_run.c:1390 bpf_prog_test_run+0x31e/0x390 kernel/bpf/syscall.c:3685 __sys_bpf+0x593/0x6d0 kernel/bpf/syscall.c:5038 __do_sys_bpf kernel/bpf/syscall.c:5124 [inline] __se_sys_bpf kernel/bpf/syscall.c:5122 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5122 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f9c0538ebe9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f9c06249038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f9c055c6090 RCX: 00007f9c0538ebe9 RDX: 0000000000000048 RSI: 0000200000000600 RDI: 000000000000000a RBP: 00007f9c05411e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f9c055c6128 R14: 00007f9c055c6090 R15: 00007ffc6a683438