INFO: task kworker/u8:18:8156 blocked for more than 144 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:18 state:D stack:0 pid:8156 tgid:8156 ppid:2 task_flags:0x4208060 flags:0x00000010 Workqueue: events_power_efficient reg_check_chans_work Call trace: __switch_to+0x2b0/0x6e0 arch/arm64/kernel/process.c:810 (T) context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1c04/0x2db8 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0x13c/0x20c kernel/sched/core.c:7283 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:7340 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0x4fc/0xed0 kernel/locking/mutex.c:820 mutex_lock_nested+0x24/0x30 kernel/locking/mutex.c:873 class_wiphy_constructor include/net/cfg80211.h:6646 [inline] reg_leave_invalid_chans net/wireless/reg.c:2454 [inline] reg_check_chans_work+0x144/0x10e8 net/wireless/reg.c:2469 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0x788/0x10b8 kernel/workqueue.c:3397 worker_thread+0x798/0xbd0 kernel/workqueue.c:3478 kthread+0x304/0x3d4 kernel/kthread.c:436 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:842 Showing all locks held in the system: 2 locks held by kworker/0:0/9: 3 locks held by kworker/u8:0/12: 3 locks held by kworker/u8:1/15: 1 lock held by khungtaskd/31: #0: ffff800088bf70c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffff800088bf70c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffff800088bf70c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x4c/0x188 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:2/39: 4 locks held by kworker/u8:4/584: 3 locks held by kworker/u8:5/887: #0: ffff0000ce1e4140 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline] #0: ffff0000ce1e4140 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x734/0x10b8 kernel/workqueue.c:3397 #1: ffff8000943b7c40 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline] #1: ffff8000943b7c40 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x73c/0x10b8 kernel/workqueue.c:3397 #2: ffff800089cca300 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:80 3 locks held by kworker/u8:6/3826: 2 locks held by udevd/4337: 2 locks held by getty/4488: #0: ffff0000cee560a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340 #1: ffff8000923ab2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x348/0xf70 drivers/tty/n_tty.c:2211 3 locks held by kworker/1:7/4807: #0: ffff0000c002b540 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline] #0: ffff0000c002b540 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x734/0x10b8 kernel/workqueue.c:3397 #1: ffff800094197c40 ((work_completion)(&helper->damage_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline] #1: ffff800094197c40 ((work_completion)(&helper->damage_work)){+.+.}-{0:0}, at: process_scheduled_works+0x73c/0x10b8 kernel/workqueue.c:3397 #2: ffff0000c7653a70 (&helper->lock){+.+.}-{4:4}, at: drm_fb_helper_fb_dirty drivers/gpu/drm/drm_fb_helper.c:236 [inline] #2: ffff0000c7653a70 (&helper->lock){+.+.}-{4:4}, at: drm_fb_helper_damage_work+0xf4/0x5e4 drivers/gpu/drm/drm_fb_helper.c:275 3 locks held by kworker/0:4/4820: #0: ffff0000c002b540 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline] #0: ffff0000c002b540 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x734/0x10b8 kernel/workqueue.c:3397 #1: ffff800093847c40 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline] #1: ffff800093847c40 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x73c/0x10b8 kernel/workqueue.c:3397 #2: ffff800089cca300 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:80 3 locks held by kworker/u8:8/4924: 2 locks held by syz-executor/6011: 1 lock held by syz-executor/6125: 3 locks held by kworker/u8:9/6134: 1 lock held by udevd/6136: 3 locks held by kworker/u8:10/6336: 2 locks held by syz-executor/6344: 3 locks held by kworker/u8:12/7158: 4 locks held by kworker/u8:13/7159: 1 lock held by syz-executor/7239: 3 locks held by kworker/u8:16/8154: 4 locks held by kworker/u8:18/8156: #0: ffff0000c004b940 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline] #0: ffff0000c004b940 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x734/0x10b8 kernel/workqueue.c:3397 #1: ffff800093d27c40 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline] #1: ffff800093d27c40 ((reg_check_chans).work){+.+.}-{0:0}, at: process_scheduled_works+0x73c/0x10b8 kernel/workqueue.c:3397 #2: ffff800089cca300 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:80 #3: ffff0000ffa40780 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6646 [inline] #3: ffff0000ffa40780 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_leave_invalid_chans net/wireless/reg.c:2454 [inline] #3: ffff0000ffa40780 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_check_chans_work+0x144/0x10e8 net/wireless/reg.c:2469 3 locks held by kworker/u8:19/8157: 3 locks held by kworker/u8:21/8159: 3 locks held by kworker/u8:22/8650: 3 locks held by kworker/u8:23/8651: 3 locks held by kworker/u8:25/8654: 1 lock held by syz.8.885/9131: #0: ffff800089cca300 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:80 8 locks held by syz.3.956/9365: 2 locks held by syz-executor/9373: 3 locks held by kworker/u8:27/9374: 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