Kernel v5.4.199, Bluez 5.64. We are using btattach. We are not seeing btattach going away, nor are we seeing a new one added (we would not expect this to happen). But we are seeing periodic messages: Jun 22 18:26:14 ecc8 user.err kernel: debugfs: Directory '0' with parent 'hci0' already present! Jun 22 18:26:14 ecc8 user.warn kernel: sysfs: cannot create duplicate filename '/devices/platform/ahb/700000.ehci/usb1/1-2/1-2.4/1-2.4:1.0/tty/ttyACM0/hci0/hci0:0' Jun 22 18:26:14 ecc8 user.warn kernel: CPU: 0 PID: 67 Comm: kworker/u3:0 Tainted: G O 5.4.199 #1 Jun 22 18:26:14 ecc8 user.warn kernel: Hardware name: Atmel AT91SAM9 Jun 22 18:26:14 ecc8 user.warn kernel: Workqueue: hci0 hci_rx_work [bluetooth] Jun 22 18:26:14 ecc8 user.warn kernel: [<c000f9e4>] (unwind_backtrace) from [<c000d3a0>] (show_stack+0x10/0x14) Jun 22 18:26:14 ecc8 user.warn kernel: [<c000d3a0>] (show_stack) from [<c014132c>] (sysfs_warn_dup+0x4c/0x60) Jun 22 18:26:14 ecc8 user.warn kernel: [<c014132c>] (sysfs_warn_dup) from [<c0141430>] (sysfs_create_dir_ns+0xb4/0xc4) Jun 22 18:26:14 ecc8 user.warn kernel: [<c0141430>] (sysfs_create_dir_ns) from [<c058d790>] (kobject_add_internal+0x148/0x338) Jun 22 18:26:14 ecc8 user.warn kernel: [<c058d790>] (kobject_add_internal) from [<c058d9fc>] (kobject_add+0x7c/0x8c) Jun 22 18:26:14 ecc8 user.warn kernel: [<c058d9fc>] (kobject_add) from [<c0334630>] (device_add+0x140/0x590) Jun 22 18:26:14 ecc8 user.warn kernel: [<c0334630>] (device_add) from [<bf103178>] (hci_conn_add_sysfs+0x50/0xb0 [bluetooth]) Jun 22 18:26:14 ecc8 user.warn kernel: [<bf103178>] (hci_conn_add_sysfs [bluetooth]) from [<bf0edf94>] (le_conn_complete_evt+0x33c/0x3fc [bluetooth]) Jun 22 18:26:14 ecc8 user.warn kernel: [<bf0edf94>] (le_conn_complete_evt [bluetooth]) from [<bf0f158c>] (hci_le_meta_evt+0x118/0xb10 [bluetooth]) Jun 22 18:26:14 ecc8 user.warn kernel: [<bf0f158c>] (hci_le_meta_evt [bluetooth]) from [<bf0f41b0>] (hci_event_packet+0x222c/0x2854 [bluetooth]) Jun 22 18:26:14 ecc8 user.warn kernel: [<bf0f41b0>] (hci_event_packet [bluetooth]) from [<bf0e4d94>] (hci_rx_work+0x1bc/0x348 [bluetooth]) Jun 22 18:26:14 ecc8 user.warn kernel: [<bf0e4d94>] (hci_rx_work [bluetooth]) from [<c002c024>] (process_one_work+0x180/0x220) Jun 22 18:26:14 ecc8 user.warn kernel: [<c002c024>] (process_one_work) from [<c002ca58>] (worker_thread+0x27c/0x348) Jun 22 18:26:14 ecc8 user.warn kernel: [<c002ca58>] (worker_thread) from [<c0031acc>] (kthread+0x130/0x13c) Jun 22 18:26:14 ecc8 user.warn kernel: [<c0031acc>] (kthread) from [<c00090e0>] (ret_from_fork+0x14/0x34) Jun 22 18:26:14 ecc8 user.warn kernel: Exception stack(0xc6075fb0 to 0xc6075ff8) Jun 22 18:26:14 ecc8 user.warn kernel: 5fa0: 00000000 00000000 00000000 00000000 Jun 22 18:26:14 ecc8 user.warn kernel: 5fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 Jun 22 18:26:14 ecc8 user.warn kernel: 5fe0: 00000000 00000000 00000000 00000000 00000013 00000000 Is this to be expected? If not, how can I track this one down?
