INFO: task syz.0.64:6117 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.64 state:D stack:23144 pid:6117 ppid:5918 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5380 [inline] __schedule+0x14d2/0x44d0 kernel/sched/core.c:6699 schedule+0xbd/0x170 kernel/sched/core.c:6773 perf_pending_task_sync kernel/events/core.c:5242 [inline] _free_event+0x174/0xf30 kernel/events/core.c:5248 put_event kernel/events/core.c:5376 [inline] perf_event_release_kernel+0x836/0x8c0 kernel/events/core.c:5501 perf_release+0x3b/0x40 kernel/events/core.c:5511 __fput+0x234/0x970 fs/file_table.c:384 task_work_run+0x1ce/0x250 kernel/task_work.c:239 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0x90b/0x23c0 kernel/exit.c:883 do_group_exit+0x21b/0x2d0 kernel/exit.c:1024 get_signal+0x12fc/0x1400 kernel/signal.c:2902 arch_do_signal_or_restart+0x9c/0x7b0 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xf6/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fd4a498f6c9 RSP: 002b:00007ffe5557b198 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: fffffffffffffff2 RBX: 00007fd4a4be5fa0 RCX: 00007fd4a498f6c9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000630c1000 RBP: 00007fd4a4a11f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007fd4a4be5fa0 R14: 00007fd4a4be5fa0 R15: 0000000000000006 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8cd2fee0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8cd2fee0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8cd2fee0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 2 locks held by getty/5551: #0: ffff88823bde20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217 2 locks held by syz.2.90/6791: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 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+0x16c/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x39b/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf41/0xf80 kernel/hung_task.c:379 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 6791 Comm: syz.2.90 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:get_current arch/x86/include/asm/current.h:41 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x60 kernel/kcov.c:215 Code: 00 00 f3 0f 1e fa 53 48 89 fb e8 13 00 00 00 48 8b 3d 0c 00 c5 0c 48 89 de 5b e9 a3 8a 56 00 cc cc cc f3 0f 1e fa 48 8b 04 24 <65> 48 8b 0d 20 28 7e 7e 65 8b 15 21 28 7e 7e 81 e2 00 01 ff 00 74 RSP: 0018:ffffc900001f0558 EFLAGS: 00000086 RAX: ffffffff813ad979 RBX: ffffc90004b07f78 RCX: ffff888017f51e00 RDX: 0000000000010000 RSI: ffffffff8cb9e7a0 RDI: ffffc90004b07f78 RBP: ffffc900001f06f0 R08: ffff888017f51e00 R09: 0000000000000003 R10: 0000000000000004 R11: 0000000000010000 R12: ffffc900001f06a0 R13: dffffc0000000000 R14: ffffc90004b07f78 R15: ffffc900001f06d6 FS: 000055555b516500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055c9ad601000 CR3: 0000000024aa1000 CR4: 00000000003506e0 Call Trace: __read_once_word_nocheck+0x9/0x10 include/asm-generic/rwonce.h:66 get_reg arch/x86/kernel/unwind_orc.c:-1 [inline] unwind_next_frame+0x1bf9/0x2970 arch/x86/kernel/unwind_orc.c:643 perf_callchain_kernel+0x465/0x5c0 arch/x86/events/core.c:2780 get_perf_callchain+0x223/0x4d0 kernel/events/callchain.c:204 perf_callchain kernel/events/core.c:7740 [inline] perf_sample_save_callchain include/linux/perf_event.h:1232 [inline] perf_prepare_sample+0x3a2/0x1d20 kernel/events/core.c:7784 __perf_event_output kernel/events/core.c:7972 [inline] perf_event_output_forward+0x152/0x3a0 kernel/events/core.c:7993 __perf_event_overflow+0x447/0x630 kernel/events/core.c:9718 perf_swevent_hrtimer+0x3bc/0x530 kernel/events/core.c:11188 __run_hrtimer kernel/time/hrtimer.c:1750 [inline] __hrtimer_run_queues+0x4df/0xc40 kernel/time/hrtimer.c:1814 hrtimer_interrupt+0x3c9/0x9c0 kernel/time/hrtimer.c:1876 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline] __sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:unwind_get_return_address+0x5/0xc0 arch/x86/kernel/unwind_orc.c:365 Code: d9 80 e1 07 80 c1 03 38 c1 0f 8c 49 ff ff ff 48 89 df e8 2e 49 a2 00 e9 3c ff ff ff e8 14 2b 34 09 0f 1f 40 00 f3 0f 1e fa 55 <41> 57 41 56 53 48 89 fb 49 be 00 00 00 00 00 fc ff df e8 d4 ed 4a RSP: 0018:ffffc90004b06b98 EFLAGS: 00000293 RAX: ffffffff81321b22 RBX: ffffc90004b06c60 RCX: ffff888017f51e00 RDX: 0000000000000000 RSI: 0000000080000000 RDI: ffffc90004b06ba8 RBP: ffffc90004b06c30 R08: ffff888017f51e00 R09: 0000000000000003 R10: 0000000000000004 R11: 0000000000000000 R12: ffffffff890a1e63 R13: 00000000000000b8 R14: ffffffff81746cb0 R15: ffffc90004b06ba8 arch_stack_walk+0x11d/0x190 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767 slab_alloc_node mm/slub.c:3495 [inline] slab_alloc mm/slub.c:3503 [inline] __kmem_cache_alloc_lru mm/slub.c:3510 [inline] kmem_cache_alloc+0x11e/0x2e0 mm/slub.c:3519 kmem_cache_zalloc include/linux/slab.h:711 [inline] __kernfs_new_node+0xd8/0x7e0 fs/kernfs/dir.c:624 kernfs_new_node+0x14c/0x260 fs/kernfs/dir.c:700 __kernfs_create_file+0x4b/0x2e0 fs/kernfs/file.c:1068 sysfs_add_file_mode_ns+0x238/0x300 fs/sysfs/file.c:294 create_files fs/sysfs/group.c:64 [inline] internal_create_group+0x428/0xd00 fs/sysfs/group.c:152 netdev_queue_add_kobject net/core/net-sysfs.c:1699 [inline] netdev_queue_update_kobjects+0x228/0x480 net/core/net-sysfs.c:1745 register_queue_kobjects net/core/net-sysfs.c:1806 [inline] netdev_register_kobject+0x269/0x310 net/core/net-sysfs.c:2046 register_netdevice+0x128f/0x1ae0 net/core/dev.c:10280 __ip_tunnel_create+0x3b4/0x4c0 net/ipv4/ip_tunnel.c:267 ip_tunnel_init_net+0x2c3/0x770 net/ipv4/ip_tunnel.c:1104 ops_init+0x397/0x640 net/core/net_namespace.c:139 setup_net+0x3a5/0xa00 net/core/net_namespace.c:343 copy_net_ns+0x36d/0x5e0 net/core/net_namespace.c:520 create_new_namespaces+0x3d3/0x6f0 kernel/nsproxy.c:110 copy_namespaces+0x430/0x4a0 kernel/nsproxy.c:179 copy_process+0x1700/0x3d70 kernel/fork.c:2509 kernel_clone+0x21b/0x840 kernel/fork.c:2914 __do_sys_clone kernel/fork.c:3057 [inline] __se_sys_clone kernel/fork.c:3041 [inline] __x64_sys_clone+0x18c/0x1e0 kernel/fork.c:3041 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f5b82f8f6c9 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:00007fff14a722a8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007f5b831e5fa0 RCX: 00007f5b82f8f6c9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000630c1000 RBP: 00007f5b83011f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f5b831e5fa0 R14: 00007f5b831e5fa0 R15: 0000000000000006