I also had this issue, which first manifested by bluetoothd being completely unresponsive and being unkillable, even with SIGKILL. The whole system would lag at regular intervals.
After a hot reboot (no power cycle), the lag went away but it was impossible to activate bluetooth and dmesg showed the same messages as above: Bluetooth: hci0: command 0xfc05 tx timeout Bluetooth: hci0: Reading Intel version information failed Finally after a cold power off and then back on, everything started working again. So it would seem that there is actually some hardware bug here, because the issue persists across reboots if the bluetooth chip is not power cycled. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1859592 Title: Bluetooth unavailable after updates - Reading Intel version information failed (-110) Status in linux package in Ubuntu: Invalid Bug description: After 10 days of uptime with automatic updates, I rebooted. Bluetooth, which I use every day, is no longer available. $ dmesg | grep -i bluetooth [ 4.846072] Bluetooth: Core ver 2.22 [ 4.846088] Bluetooth: HCI device and connection manager initialized [ 4.846092] Bluetooth: HCI socket layer initialized [ 4.846094] Bluetooth: L2CAP socket layer initialized [ 4.846096] Bluetooth: SCO socket layer initialized [ 5.434081] Bluetooth: BNEP (Ethernet Emulation) ver 1.3 [ 5.434082] Bluetooth: BNEP filters: protocol multicast [ 5.434086] Bluetooth: BNEP socket layer initialized [ 6.874125] Bluetooth: hci0: command 0xfc05 tx timeout [ 6.874129] Bluetooth: hci0: Reading Intel version information failed (-110) $ uname -a Linux abu 5.3.2-050302-generic #201910010731 SMP Tue Oct 1 07:33:48 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux AMD Ryzen 5 3400G (Picasso, Raven Ridge) (Asrock A300) Ubuntu 18.04 LTS. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1859592/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
