INFO: task kworker/0:2:972 blocked for more than 143 seconds. Not tainted 6.15.0-syzkaller-11061-g7f9039c524a3 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:2 state:D stack:23432 pid:972 tgid:972 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: events reg_todo Call Trace: context_switch kernel/sched/core.c:5392 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6781 __schedule_loop kernel/sched/core.c:6859 [inline] schedule+0x165/0x360 kernel/sched/core.c:6874 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6931 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:747 class_wiphy_constructor include/net/cfg80211.h:6062 [inline] reg_process_self_managed_hints+0xad/0x1b0 net/wireless/reg.c:3209 reg_todo+0x78d/0x890 net/wireless/reg.c:3222 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x711/0x8a0 kernel/kthread.c:464 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 kmmpd-loop5:6047 blocked for more than 143 seconds. Not tainted 6.15.0-syzkaller-11061-g7f9039c524a3 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kmmpd-loop5 state:D stack:28008 pid:6047 tgid:6047 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5392 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6781 __schedule_loop kernel/sched/core.c:6859 [inline] schedule+0x165/0x360 kernel/sched/core.c:6874 io_schedule+0x80/0xd0 kernel/sched/core.c:7719 bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:247 __wait_on_bit+0xb9/0x310 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0x123/0x170 kernel/sched/wait_bit.c:64 wait_on_buffer include/linux/buffer_head.h:422 [inline] write_mmp_block_thawed+0x201/0x2a0 fs/ext4/mmp.c:52 write_mmp_block+0x13e/0x3b0 fs/ext4/mmp.c:67 kmmpd+0x391/0xa10 fs/ext4/mmp.c:178 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 2 locks held by kthreadd/2: 2 locks held by kworker/u8:0/12: #0: ffff888146ab1948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff888146ab1948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321 #1: ffffc90000117bc0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90000117bc0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321 3 locks held by kworker/u8:1/13: 2 locks held by kworker/1:0/24: 1 lock held by khungtaskd/31: #0: ffffffff8e13f080 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13f080 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13f080 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 3 locks held by kworker/u8:2/36: 2 locks held by kworker/1:1/43: 3 locks held by kworker/u8:3/49: 3 locks held by kworker/u8:4/72: 3 locks held by kworker/0:1H/92: #0: ffff8881412c7148 ((wq_completion)kblockd){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff8881412c7148 ((wq_completion)kblockd){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321 #1: ffffc900025b7bc0 ((work_completion)(&q->timeout_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc900025b7bc0 ((work_completion)(&q->timeout_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321 #2: ffffffff8e144bb8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #2: ffffffff8e144bb8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998 3 locks held by kworker/u8:5/233: 4 locks held by kworker/0:2/972: #0: ffff88801a478d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801a478d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321 #1: ffffc900037dfbc0 (reg_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc900037dfbc0 (reg_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321 #2: ffffffff8f50d688 (rtnl_mutex){+.+.}-{4:4}, at: reg_todo+0x1c/0x890 net/wireless/reg.c:3219 #3: ffff88807fbd8768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6062 [inline] #3: ffff88807fbd8768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_process_self_managed_hints+0xad/0x1b0 net/wireless/reg.c:3209 2 locks held by kworker/1:2/2092: 3 locks held by kworker/R-ipv6_/3165: #0: ffff88814cbe8948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88814cbe8948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321 #1: ffffc9000bc87ba0 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000bc87ba0 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321 #2: ffffffff8f50d688 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8f50d688 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4738 2 locks held by kworker/R-bat_e/3395: 3 locks held by kworker/u8:6/3734: 3 locks held by kworker/u8:7/3736: 1 lock held by klogd/5187: 1 lock held by udevd/5198: 1 lock held by dhcpcd/5492: 4 locks held by dhcpcd/5493: 2 locks held by getty/5587: #0: ffff88814cf090a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 4 locks held by syz-executor/5814: 2 locks held by syz-executor/5829: 7 locks held by kworker/u9:2/5833: #0: ffff8880264fe948 ((wq_completion)hci4){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff8880264fe948 ((wq_completion)hci4){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321 #1: ffffc90003e0fbc0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90003e0fbc0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321 #2: ffff88802e194d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d4/0x3a0 net/bluetooth/hci_sync.c:331 #3: ffff88802e194078 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0x1eb/0xdf0 net/bluetooth/hci_sync.c:5601 #4: ffffffff8f6756a8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:2047 [inline] #4: ffffffff8f6756a8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_failed+0x165/0x310 net/bluetooth/hci_conn.c:1275 #5: ffff888141ea0338 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x70/0x680 net/bluetooth/l2cap_core.c:1762 #6: ffffffff8e144bb8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #6: ffffffff8e144bb8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998 5 locks held by kworker/u9:3/5836: #0: ffff888143774948 ((wq_completion)hci1){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff888143774948 ((wq_completion)hci1){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321 #1: ffffc90003e2fbc0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90003e2fbc0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321 #2: ffff8880334b4d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d4/0x3a0 net/bluetooth/hci_sync.c:331 #3: ffff8880334b4078 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0x1eb/0xdf0 net/bluetooth/hci_sync.c:5601 #4: ffffffff8f6756a8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:2047 [inline] #4: ffffffff8f6756a8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_failed+0x165/0x310 net/bluetooth/hci_conn.c:1275 1 lock held by udevd/5837: 3 locks held by syz-executor/5839: 1 lock held by syz-executor/5841: 3 locks held by syz-executor/5843: 3 locks held by kworker/0:4/5868: #0: ffff88801a479d48 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801a479d48 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321 #1: ffffc90003d6fbc0 ((crda_timeout).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90003d6fbc0 ((crda_timeout).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321 #2: ffffffff8f50d688 (rtnl_mutex){+.+.}-{4:4}, at: crda_timeout_work+0x15/0x50 net/wireless/reg.c:541 2 locks held by kworker/1:3/5886: 2 locks held by kworker/1:4/5887: 2 locks held by kworker/1:5/5888: 3 locks held by kworker/u8:8/5919: 3 locks held by kworker/0:6/5925: #0: ffff88801a479d48 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801a479d48 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321 #1: ffffc900037ffbc0 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc900037ffbc0 ((reg_check_chans).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321 #2: ffffffff8f50d688 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0x95/0xf00 net/wireless/reg.c:2483 2 locks held by kworker/1:6/5929: 2 locks held by kworker/1:7/5949: 4 locks held by syz.5.33/6037: 1 lock held by kmmpd-loop5/6047: #0: ffff888026992428 (sb_writers#4){.+.+}-{0:0}, at: kmmpd+0x391/0xa10 fs/ext4/mmp.c:178 7 locks held by kworker/u8:9/6055: 2 locks held by kworker/1:8/6077: 3 locks held by kworker/u8:10/6078: 3 locks held by kworker/u8:11/6079: 3 locks held by udevadm/6080: 3 locks held by kworker/u8:12/6082: 5 locks held by kworker/u8:13/6084: 2 locks held by kworker/1:9/6085: 1 lock held by kworker/u8:14/6087: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-syzkaller-11061-g7f9039c524a3 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:470 kthread+0x711/0x8a0 kernel/kthread.c:464 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 6084 Comm: kworker/u8:13 Not tainted 6.15.0-syzkaller-11061-g7f9039c524a3 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: events_unbound cfg80211_wiphy_work RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_preemption_disabled+0x1e/0x120 lib/smp_processor_id.c:16 Code: 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 53 48 83 ec 10 65 48 8b 05 fe 5d 37 07 48 89 44 24 08 65 8b 05 06 5e 37 07 <65> 8b 0d fb 5d 37 07 f7 c1 ff ff ff 7f 74 23 65 48 8b 0d db 5d 37 RSP: 0018:ffffc90000006fc0 EFLAGS: 00000086 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 4b105e296906c500 RDX: 0000000000000000 RSI: ffffffff8db5d4ed RDI: ffffffff8be27440 RBP: ffffffff81729e15 R08: 0000000000000000 R09: ffffffff81729e15 R10: dffffc0000000000 R11: ffffffff81acf580 R12: 0000000000000002 R13: ffffffff8e13f080 R14: 0000000000000000 R15: 0000000000000246 FS: 0000000000000000(0000) GS:ffff888125c5e000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffcaf5ebdfc CR3: 0000000058b5b000 CR4: 0000000000350ef0 Call Trace: lockdep_recursion_finish kernel/locking/lockdep.c:473 [inline] lock_acquire+0x130/0x360 kernel/locking/lockdep.c:5873 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 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 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 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4147 [inline] slab_alloc_node mm/slub.c:4196 [inline] kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4203 __skb_ext_alloc net/core/skbuff.c:6980 [inline] skb_ext_add+0x148/0x8f0 net/core/skbuff.c:7083 nf_bridge_alloc include/net/netfilter/br_netfilter.h:12 [inline] br_nf_pre_routing_ipv6+0x132/0x6b0 net/bridge/br_netfilter_ipv6.c:172 nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline] nf_hook_bridge_pre net/bridge/br_input.c:283 [inline] br_handle_frame+0x982/0x14c0 net/bridge/br_input.c:434 __netif_receive_skb_core+0x10e1/0x4180 net/core/dev.c:5863 __netif_receive_skb_one_core net/core/dev.c:5975 [inline] __netif_receive_skb+0x72/0x380 net/core/dev.c:6090 process_backlog+0x60e/0x14f0 net/core/dev.c:6442 __napi_poll+0xc7/0x480 net/core/dev.c:7414 napi_poll net/core/dev.c:7478 [inline] net_rx_action+0x707/0xe30 net/core/dev.c:7605 handle_softirqs+0x286/0x870 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] cfg80211_inform_single_bss_data+0x13d2/0x1ac0 net/wireless/scan.c:2383 cfg80211_inform_bss_data+0x1fb/0x3b20 net/wireless/scan.c:3222 cfg80211_inform_bss_frame_data+0x362/0x700 net/wireless/scan.c:3317 ieee80211_bss_info_update+0x746/0x9e0 net/mac80211/scan.c:226 ieee80211_rx_bss_info net/mac80211/ibss.c:1094 [inline] ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1573 [inline] ieee80211_ibss_rx_queued_mgmt+0xa36/0x2ae0 net/mac80211/ibss.c:1600 ieee80211_iface_process_skb net/mac80211/iface.c:1668 [inline] ieee80211_iface_work+0x806/0xfe0 net/mac80211/iface.c:1722 cfg80211_wiphy_work+0x2df/0x460 net/wireless/core.c:435 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245