INFO: task syz.6.2852:14742 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.6.2852 state:D stack:26304 pid:14742 ppid: 8349 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 perf_pending_task_sync+0x13c/0x1c0 kernel/events/core.c:5127 _free_event+0x34/0xe60 kernel/events/core.c:5133 put_event kernel/events/core.c:5258 [inline] perf_event_release_kernel+0x832/0x8c0 kernel/events/core.c:5383 perf_release+0x37/0x40 kernel/events/core.c:5393 __fput+0x234/0x930 fs/file_table.c:311 task_work_run+0x125/0x1a0 kernel/task_work.c:188 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0x61e/0x20a0 kernel/exit.c:883 do_group_exit+0x12e/0x300 kernel/exit.c:997 get_signal+0x6ca/0x12c0 kernel/signal.c:2900 arch_do_signal_or_restart+0xc1/0x1300 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fc2457c2ba9 RSP: 002b:00007fc243a09038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: 0000000000000009 RBX: 00007fc245a0a090 RCX: 00007fc2457c2ba9 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000000 RBP: 00007fc245845e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc245a0a128 R14: 00007fc245a0a090 R15: 00007ffd87e55308 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c11c660 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 4 locks held by kworker/u4:3/1215: 2 locks held by getty/3948: #0: ffff88814cccf098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002d032e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158 2 locks held by kworker/u4:18/4410: 3 locks held by kworker/1:23/11478: #0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc9000359fd00 (fqdir_free_work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffffffff8c120ff0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0xa1/0x4b0 kernel/rcu/tree.c:4043 3 locks held by kworker/1:28/11483: #0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc900035ffd00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffffffff8c120ff0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0xa1/0x4b0 kernel/rcu/tree.c:4043 2 locks held by kworker/1:30/11485: #0: ffff888016872138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc90003e5fd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 3 locks held by syz.7.4056/18877: 2 locks held by syz.0.4071/18921: #0: ffffffff8d238048 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:699 [inline] #0: ffffffff8d238048 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3d/0x1b0 drivers/net/tun.c:3440 #1: ffffffff8c1210e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #1: ffffffff8c1210e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x347/0x6b0 kernel/rcu/tree_exp.h:845 ============================================= 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 07/12/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xe0f/0xe50 kernel/hung_task.c:369 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 18877 Comm: syz.7.4056 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline] RIP: 0010:static_key_false include/linux/jump_label.h:212 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:156 [inline] RIP: 0010:wrmsr arch/x86/include/asm/msr.h:263 [inline] RIP: 0010:native_apic_msr_write+0x35/0x50 arch/x86/include/asm/apic.h:208 Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 89 f6 31 d2 e9 ff b6 c7 02 66 2e 0f 1f 84 00 00 00 00 00 RSP: 0018:ffffc90000007e48 EFLAGS: 00000046 RAX: 0000000000000182 RBX: 0000000000000182 RCX: 0000000000000838 RDX: 0000000000000000 RSI: 0000000000000182 RDI: 0000000000000838 RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff1ad323e R10: fffffbfff1ad323e R11: 1ffffffff1ad323d R12: dffffc0000000000 R13: 0000000010004d2c R14: ffffffff8bbc29d8 R15: dffffc0000000000 FS: 00007fd34dea96c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fdc08e42ad8 CR3: 000000004dced000 CR4: 00000000003506f0 DR0: 0000200000000300 DR1: 0000200000000300 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: apic_write arch/x86/include/asm/apic.h:395 [inline] lapic_next_event+0x5b/0x70 arch/x86/kernel/apic/apic.c:468 clockevents_program_event+0x1bc/0x310 kernel/time/clockevents.c:334 hrtimer_interrupt+0x4de/0x8d0 kernel/time/hrtimer.c:1829 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline] __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:lock_acquire+0x1f2/0x3f0 kernel/locking/lockdep.c:5627 Code: 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f6 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 66 43 c7 44 3d 09 00 00 43 c6 44 3d 0b RSP: 0018:ffffc90002f9f620 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 9ade18e8508d3200 RDX: 0000000000000000 RSI: ffffffff8a0b2ac0 RDI: ffffffff8a59a480 RBP: ffffc90002f9f740 R08: dffffc0000000000 R09: fffffbfff1ff7819 R10: fffffbfff1ff7819 R11: 1ffffffff1ff7818 R12: ffffffff8c11c660 R13: 1ffff920005f3ed0 R14: 0000000000000246 R15: dffffc0000000000 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312 rcu_read_lock include/linux/rcupdate.h:739 [inline] inet_twsk_purge+0x119/0x810 net/ipv4/inet_timewait_sock.c:268 ops_exit_list net/core/net_namespace.c:177 [inline] setup_net+0x822/0x9f0 net/core/net_namespace.c:365 copy_net_ns+0x348/0x5b0 net/core/net_namespace.c:503 create_new_namespaces+0x3d3/0x6f0 kernel/nsproxy.c:110 copy_namespaces+0x37d/0x3e0 kernel/nsproxy.c:178 copy_process+0x180f/0x3e00 kernel/fork.c:2293 kernel_clone+0x219/0x930 kernel/fork.c:2679 __do_sys_clone kernel/fork.c:2796 [inline] __se_sys_clone kernel/fork.c:2780 [inline] __x64_sys_clone+0x170/0x1c0 kernel/fork.c:2780 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fd34fc41ba9 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:00007fd34dea8fe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007fd34fe88fa0 RCX: 00007fd34fc41ba9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000 RBP: 00007fd34fcc4e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007fd34fe89038 R14: 00007fd34fe88fa0 R15: 00007ffe2560f2f8