INFO: task syz.2.559:6066 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.559 state:D stack:23064 pid:6066 ppid:4273 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x107f/0x4030 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+0x176/0x1050 kernel/events/core.c:5037 put_event kernel/events/core.c:5162 [inline] perf_event_release_kernel+0x7c4/0x850 kernel/events/core.c:5287 perf_release+0x37/0x40 kernel/events/core.c:5297 __fput+0x20a/0x8b0 fs/file_table.c:320 task_work_run+0x1d0/0x260 kernel/task_work.c:203 get_signal+0x118d/0x1340 kernel/signal.c:2649 arch_do_signal_or_restart+0xc4/0x1310 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: 0033:0x7fee2699de99 RSP: 002b:00007fee278ddfd8 EFLAGS: 00000202 ORIG_RAX: 0000000000000038 RAX: fffffffffffffffc RBX: 00007fee26c25fa0 RCX: 00007fee2699de99 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000c0126080 RBP: 00007fee26a33eaf R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000 R13: 00007fee26c26038 R14: 00007fee26c25fa0 R15: 00007ffc32815a48 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8cb2e4f0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8cb2ed10 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/28: #0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6527 1 lock held by klogd/3627: #0: ffff8880b8f3ad18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x25/0x130 kernel/sched/core.c:538 2 locks held by getty/4029: #0: ffff88814cc6f098 (&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+0x41e/0x1360 drivers/tty/n_tty.c:2198 3 locks held by syz.4.1364/8626: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/25/2026 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+0xf0e/0xf50 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: 8626 Comm: syz.4.1364 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/25/2026 RIP: 0010:asm_sysvec_apic_timer_interrupt+0x0/0x20 arch/x86/include/asm/idtentry.h:690 Code: e9 f5 04 00 00 90 90 90 90 90 0f 01 ca fc 6a ff e8 f5 03 00 00 48 89 c4 48 89 e7 e8 da 37 f0 ff e9 d5 04 00 00 90 90 90 90 90 <0f> 01 ca fc 6a ff e8 d5 03 00 00 48 89 c4 48 89 e7 e8 2a 36 f0 ff RSP: 0018:ffffc9000d9af228 EFLAGS: 00000046 RAX: 1ffff11047fffa01 RBX: fffff91ffff61dd9 RCX: ffffffff81b9c68e RDX: 0000000000000001 RSI: 0000000000000128 RDI: ffffe8ffffb0eda0 RBP: 0000000000000004 R08: ffffe8ffffb0eec7 R09: 1ffffd1ffff61dd8 R10: dffffc0000000000 R11: fffff91ffff61db4 R12: dffffc0000000001 R13: 1ffffffff1c42476 R14: 1ffffd1ffff61db4 R15: fffff91ffff61db4 FS: 00007f21ce9226c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2d89bed2f8 CR3: 000000007d6b6000 CR4: 00000000003506f0 DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:85 [inline] RIP: 0010:memory_is_nonzero mm/kasan/generic.c:106 [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+0xaa/0x290 mm/kasan/generic.c:189 Code: 41 80 3b 00 0f 85 86 01 00 00 49 ff c3 48 ff c3 75 ee e9 18 01 00 00 44 89 dd 83 e5 07 0f 84 b5 00 00 00 41 80 3b 00 4d 89 df <0f> 85 97 01 00 00 83 fd 07 0f 84 8d 00 00 00 43 80 3c 26 00 0f 85 RSP: 0018:ffffc9000d9af258 EFLAGS: 00000246 memset+0x1e/0x40 mm/kasan/shadow.c:44 pcpu_alloc+0xf0e/0x16b0 mm/percpu.c:1882 snmp6_alloc_dev net/ipv6/addrconf.c:339 [inline] ipv6_add_dev+0x407/0x1110 net/ipv6/addrconf.c:404 addrconf_notify+0x634/0xf60 net/ipv6/addrconf.c:3595 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:455 call_netdevice_notifiers_extack net/core/dev.c:2052 [inline] call_netdevice_notifiers net/core/dev.c:2066 [inline] register_netdevice+0x16a8/0x1b80 net/core/dev.c:10276 __ip_tunnel_create+0x346/0x450 net/ipv4/ip_tunnel.c:267 ip_tunnel_init_net+0x2ac/0x7a0 net/ipv4/ip_tunnel.c:1104 ops_init+0x360/0x5e0 net/core/net_namespace.c:138 setup_net+0x4f2/0xbd0 net/core/net_namespace.c:336 copy_net_ns+0x33e/0x5b0 net/core/net_namespace.c:508 create_new_namespaces+0x3ce/0x700 kernel/nsproxy.c:110 copy_namespaces+0x3ae/0x410 kernel/nsproxy.c:178 copy_process+0x19ef/0x40c0 kernel/fork.c:2360 kernel_clone+0x24b/0x900 kernel/fork.c:2764 __do_sys_clone kernel/fork.c:2905 [inline] __se_sys_clone kernel/fork.c:2889 [inline] __x64_sys_clone+0x1a7/0x220 kernel/fork.c:2889 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f21cd99de99 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f21ce921fd8 EFLAGS: 00000202 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007f21cdc25fa0 RCX: 00007f21cd99de99 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000c0126080 RBP: 00007f21cda33eaf R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000 R13: 00007f21cdc26038 R14: 00007f21cdc25fa0 R15: 00007ffdecd6c988