INFO: task kworker/1:4:5926 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:4 state:D stack:23144 pid:5926 tgid:5926 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: events rfkill_global_led_trigger_worker Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760 rfkill_global_led_trigger_worker+0x27/0xd0 net/rfkill/core.c:182 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task syz.2.866:9228 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.866 state:D stack:24104 pid:9228 tgid:9228 ppid:5874 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760 rfkill_unregister+0xc8/0x220 net/rfkill/core.c:1145 nfc_unregister_device+0x96/0x2a0 net/nfc/core.c:1167 virtual_ncidev_close+0x56/0x90 drivers/nfc/virtual_ncidev.c:172 __fput+0x449/0xa70 fs/file_table.c:468 task_work_run+0x1d1/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:43 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fdd37b8ebe9 RSP: 002b:00007ffe088a6e98 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007fdd37dc7da0 RCX: 00007fdd37b8ebe9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007fdd37dc7da0 R08: 00000000000001c0 R09: 0000001a088a718f R10: 00007fdd37dc7cb0 R11: 0000000000000246 R12: 000000000003571b R13: 00007fdd37dc5fa0 R14: ffffffffffffffff R15: 00007ffe088a6fb0 INFO: task syz.1.869:9247 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.869 state:D stack:24808 pid:9247 tgid:9244 ppid:5865 task_flags:0x400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760 device_lock include/linux/device.h:911 [inline] nfc_dev_down net/nfc/core.c:143 [inline] nfc_rfkill_set_block+0x50/0x2e0 net/nfc/core.c:179 rfkill_set_block+0x1cf/0x440 net/rfkill/core.c:346 rfkill_fop_write+0x44b/0x570 net/rfkill/core.c:1301 vfs_write+0x27b/0xb30 fs/read_write.c:684 ksys_write+0x145/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd424b8ebe9 RSP: 002b:00007fd425a03038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fd424dc5fa0 RCX: 00007fd424b8ebe9 RDX: 0000000000000008 RSI: 0000200000000080 RDI: 0000000000000005 RBP: 00007fd424c11e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd424dc6038 R14: 00007fd424dc5fa0 R15: 00007ffe426e3de8 Showing all locks held in the system: 4 locks held by ksoftirqd/1/23: 1 lock held by khungtaskd/31: #0: ffffffff8e139f20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e139f20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e139f20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5626: #0: ffff8880305650a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 3 locks held by kworker/1:4/5926: #0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc90004947bc0 ((work_completion)(&rfkill_global_led_trigger_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90004947bc0 ((work_completion)(&rfkill_global_led_trigger_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8f812fe8 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_global_led_trigger_worker+0x27/0xd0 net/rfkill/core.c:182 2 locks held by syz.2.866/9228: #0: ffff888033d39100 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #0: ffff888033d39100 (&dev->mutex){....}-{4:4}, at: nfc_unregister_device+0x63/0x2a0 net/nfc/core.c:1165 #1: ffffffff8f812fe8 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_unregister+0xc8/0x220 net/rfkill/core.c:1145 2 locks held by syz.1.869/9247: #0: ffffffff8f812fe8 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_fop_write+0x191/0x570 net/rfkill/core.c:1293 #1: ffff888033d39100 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #1: ffff888033d39100 (&dev->mutex){....}-{4:4}, at: nfc_dev_down net/nfc/core.c:143 [inline] #1: ffff888033d39100 (&dev->mutex){....}-{4:4}, at: nfc_rfkill_set_block+0x50/0x2e0 net/nfc/core.c:179 3 locks held by syz.3.920/9488: #0: ffffffff8e9c1b88 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 #1: ffff888077c53100 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #1: ffff888077c53100 (&dev->mutex){....}-{4:4}, at: nfc_register_device+0xa1/0x320 net/nfc/core.c:1128 #2: ffffffff8f812fe8 (rfkill_global_mutex){+.+.}-{4:4}, at: rfkill_register+0x37/0x8e0 net/rfkill/core.c:1071 1 lock held by syz.0.924/9513: #0: ffffffff8e9c1b88 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz.0.924/9515: #0: ffffffff8e9c1b88 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz.0.924/9516: #0: ffffffff8e9c1b88 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz-executor/9554: #0: ffffffff8e9c1b88 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz-executor/9570: #0: ffffffff8e9c1b88 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz.4.946/9650: #0: ffffffff8e9c1b88 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz-executor/9692: #0: ffffffff8e9c1b88 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz-executor/9694: #0: ffffffff8e9c1b88 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz-executor/9700: #0: ffffffff8e9c1b88 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz-executor/9702: #0: ffffffff8e9c1b88 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz-executor/9704: #0: ffffffff8e9c1b88 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz-executor/9706: #0: ffffffff8e9c1b88 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz-executor/9708: #0: ffffffff8e9c1b88 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz-executor/9714: #0: ffffffff8e9c1b88 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz-executor/9716: #0: ffffffff8e9c1b88 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz-executor/9718: #0: ffffffff8e9c1b88 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 1 lock held by syz-executor/9720: #0: ffffffff8e9c1b88 (misc_mtx){+.+.}-{4:4}, at: misc_open+0x51/0x330 drivers/char/misc.c:125 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline] watchdog+0xf93/0xfe0 kernel/hung_task.c:491 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 1168 Comm: kworker/u8:8 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: bat_events batadv_nc_worker RIP: 0010:hlock_class kernel/locking/lockdep.c:234 [inline] RIP: 0010:check_wait_context kernel/locking/lockdep.c:4854 [inline] RIP: 0010:__lock_acquire+0x332/0xd20 kernel/locking/lockdep.c:5187 Code: e5 15 09 d5 09 cd 44 09 f5 41 89 6c c7 20 45 89 44 c7 24 4c 89 7c 24 10 4d 8d 34 c7 81 e5 ff 1f 00 00 48 0f a3 2d 3e df 0a 12 <73> 10 48 69 c5 c8 00 00 00 48 8d 80 10 43 49 93 eb 40 83 3d a5 6e RSP: 0018:ffffc90000a07c08 EFLAGS: 00000003 RAX: 0000000000000019 RBX: ffffffff8e139f20 RCX: 0000000000000007 RDX: 0000000000000000 RSI: 0000000000002000 RDI: ffff8880270b0000 RBP: 0000000000000007 R08: 0000000000000000 R09: ffffffff8172c195 R10: ffffc90000a07eb8 R11: fffff52000140fd9 R12: 0000000000022000 R13: 0000000000000000 R14: ffff8880270b0bb8 R15: ffff8880270b0af0 FS: 0000000000000000(0000) GS:ffff888125d18000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fff70aa2fec CR3: 0000000030772000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479 __unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:758 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:243 [inline] __kasan_slab_free+0x5b/0x80 mm/kasan/common.c:275 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2422 [inline] slab_free mm/slub.c:4695 [inline] kmem_cache_free+0x18f/0x400 mm/slub.c:4797 nft_synproxy_eval_v6+0x376/0x560 net/netfilter/nft_synproxy.c:91 nft_synproxy_do_eval+0x3d7/0x570 net/netfilter/nft_synproxy.c:145 expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline] nft_do_chain+0x409/0x1920 net/netfilter/nf_tables_core.c:285 nft_do_chain_inet+0x25d/0x340 net/netfilter/nft_chain_filter.c:161 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_slow+0xc2/0x220 net/netfilter/core.c:623 nf_hook include/linux/netfilter.h:273 [inline] NF_HOOK+0x206/0x3a0 include/linux/netfilter.h:316 ip6_input+0x16a/0x270 net/ipv6/ip6_input.c:500 NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318 __netif_receive_skb_one_core net/core/dev.c:5991 [inline] __netif_receive_skb+0xd3/0x380 net/core/dev.c:6104 process_backlog+0x60e/0x14f0 net/core/dev.c:6456 __napi_poll+0xc4/0x360 net/core/dev.c:7506 napi_poll net/core/dev.c:7569 [inline] net_rx_action+0x707/0xe30 net/core/dev.c:7696 handle_softirqs+0x283/0x870 kernel/softirq.c:579 do_softirq+0xec/0x180 kernel/softirq.c:480 __local_bh_enable_ip+0x17d/0x1c0 kernel/softirq.c:407 spin_unlock_bh include/linux/spinlock.h:396 [inline] batadv_nc_purge_paths+0x318/0x3b0 net/batman-adv/network-coding.c:471 batadv_nc_worker+0x328/0x610 net/batman-adv/network-coding.c:720 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245