rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7595/1:b..l rcu: (detected by 0, t=10502 jiffies, g=62101, q=945 ncpus=2) task:udevd state:R running task stack:21632 pid:7595 tgid:7595 ppid:4684 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5239 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6603 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6925 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:rcu_is_watching+0x67/0xb0 kernel/rcu/tree.c:727 Code: 89 f7 e8 7c 68 81 00 48 c7 c3 78 7c 03 00 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38 84 c0 75 22 8b 03 65 ff 0d 11 ef 89 7e <74> 10 83 e0 04 c1 e8 02 5b 41 5e 41 5f c3 cc cc cc cc e8 c2 ce 86 RSP: 0018:ffffc90004247710 EFLAGS: 00000286 RAX: 00000000032999ec RBX: ffff8880b9337c78 RCX: ffff8880294c9e00 RDX: ffff8880294c9e00 RSI: ffffffff8c607c20 RDI: ffffffff8c607be0 RBP: 0000000000000000 R08: ffffffff8470842b R09: 1ffffffff26e6f00 R10: dffffc0000000000 R11: fffffbfff26e6f01 R12: 0000000000000001 R13: 0000000000700002 R14: ffffffff8e297a48 R15: dffffc0000000000 rcu_read_lock_held_common kernel/rcu/update.c:109 [inline] rcu_read_lock_held+0x15/0x50 kernel/rcu/update.c:349 task_css include/linux/cgroup.h:433 [inline] task_devcgroup security/device_cgroup.c:56 [inline] devcgroup_legacy_check_permission security/device_cgroup.c:839 [inline] devcgroup_check_permission+0x1d5/0x950 security/device_cgroup.c:868 bdev_permission+0x31/0x90 block/bdev.c:738 blkdev_open+0x198/0x570 block/fops.c:619 do_dentry_open+0x970/0x1440 fs/open.c:959 vfs_open+0x3e/0x330 fs/open.c:1089 do_open fs/namei.c:3727 [inline] path_openat+0x2b3e/0x3470 fs/namei.c:3886 do_filp_open+0x235/0x490 fs/namei.c:3913 do_sys_openat2+0x13e/0x1d0 fs/open.c:1416 do_sys_open fs/open.c:1431 [inline] __do_sys_openat fs/open.c:1447 [inline] __se_sys_openat fs/open.c:1442 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1442 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f493858b9a4 RSP: 002b:00007ffdfd607cb0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000558695a19d00 RCX: 00007f493858b9a4 RDX: 00000000000a0800 RSI: 0000558695a176a0 RDI: 00000000ffffff9c RBP: 0000558695a176a0 R08: 00000000ffffffff R09: 7fffffffffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00000000000a0800 R13: 0000558695a09ae0 R14: 0000000000000001 R15: 00005586959f8910 DEBUG: holding rtnl_mutex for 511 jiffies. task:kworker/0:5 state:D stack:22160 pid:5280 tgid:5280 ppid:2 flags:0x00004000 Workqueue: events_power_efficient reg_check_chans_work Call Trace: context_switch kernel/sched/core.c:5239 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6603 __schedule_loop kernel/sched/core.c:6680 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6695 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6752 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a4/0xd70 kernel/locking/mutex.c:752 wiphy_lock include/net/cfg80211.h:6014 [inline] reg_leave_invalid_chans net/wireless/reg.c:2468 [inline] reg_check_chans_work+0x164/0xfd0 net/wireless/reg.c:2483 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:144 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Showing all locks held in the system: 2 locks held by kthreadd/2: 3 locks held by kworker/u8:1/12: 3 locks held by kworker/u8:2/35: 5 locks held by kworker/0:2/1065: 3 locks held by kworker/1:2/1687: 3 locks held by kworker/u8:8/2476: 3 locks held by kworker/u8:9/2512: 3 locks held by kworker/u8:10/2551: 3 locks held by kworker/u8:11/2567: 3 locks held by kworker/u8:12/2928: 3 locks held by kworker/u8:13/2963: 5 locks held by kworker/u9:1/4622: #0: ffff88807dfda148 ((wq_completion)hci14){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff88807dfda148 ((wq_completion)hci14){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc9000da4fd00 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc9000da4fd00 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffff888042b48d80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_cmd_sync_work+0x1ec/0x400 net/bluetooth/hci_sync.c:327 #3: ffff888042b48078 (&hdev->lock){+.+.}-{3:3}, at: hci_abort_conn_sync+0x1ea/0xde0 net/bluetooth/hci_sync.c:5512 #4: ffffffff8fded8e8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:1962 [inline] #4: ffffffff8fded8e8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_failed+0x185/0x340 net/bluetooth/hci_conn.c:1265 2 locks held by syslogd/4666: 1 lock held by klogd/4673: 1 lock held by dhcpcd/4897: 2 locks held by getty/4985: #0: ffff88802ad830a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900031232f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b5/0x1e10 drivers/tty/n_tty.c:2211 5 locks held by kworker/u9:4/5238: #0: ffff88805b861948 ((wq_completion)hci13){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff88805b861948 ((wq_completion)hci13){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc9000377fd00 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc9000377fd00 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffff88803d56cd80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_cmd_sync_work+0x1ec/0x400 net/bluetooth/hci_sync.c:327 #3: ffff88803d56c078 (&hdev->lock){+.+.}-{3:3}, at: hci_abort_conn_sync+0x1ea/0xde0 net/bluetooth/hci_sync.c:5512 #4: ffffffff8fded8e8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:1962 [inline] #4: ffffffff8fded8e8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_failed+0x185/0x340 net/bluetooth/hci_conn.c:1265 3 locks held by kworker/u9:7/5244: 4 locks held by kworker/0:5/5280: #0: ffff888015881948 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff888015881948 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90003ec7d00 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90003ec7d00 ((reg_check_chans).work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fc81d48 (rtnl_mutex){+.+.}-{3:3}, at: reg_check_chans_work+0x99/0xfd0 net/wireless/reg.c:2480 #3: ffff88803eb40768 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: wiphy_lock include/net/cfg80211.h:6014 [inline] #3: ffff88803eb40768 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: reg_leave_invalid_chans net/wireless/reg.c:2468 [inline] #3: ffff88803eb40768 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: reg_check_chans_work+0x164/0xfd0 net/wireless/reg.c:2483 2 locks held by kworker/0:6/5336: 2 locks held by udevd/7595: 2 locks held by syz-executor/10299: 1 lock held by syz.1.940/11186: 1 lock held by syz.0.954/11233: 1 lock held by syz.4.956/11236: #0: ffffffff8e93ce38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #0: ffffffff8e93ce38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:967 2 locks held by syz.4.956/11242: 2 locks held by syz.3.957/11241: ============================================= DEBUG: holding rtnl_mutex for 671 jiffies. task:kworker/0:5 state:D stack:22160 pid:5280 tgid:5280 ppid:2 flags:0x00004000 Workqueue: events_power_efficient reg_check_chans_work Call Trace: context_switch kernel/sched/core.c:5239 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6603 __schedule_loop kernel/sched/core.c:6680 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6695 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6752 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a4/0xd70 kernel/locking/mutex.c:752 wiphy_lock include/net/cfg80211.h:6014 [inline] reg_leave_invalid_chans net/wireless/reg.c:2468 [inline] reg_check_chans_work+0x164/0xfd0 net/wireless/reg.c:2483 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312