Ubuntu 14.04 LTS console running in VirtualBox in Win7 locks up when pressing Caps Lock: no further keyboard input is accepted, not even Alt+CursorRight or Ctrl+Alt+Del (issued from VirtualBox).
Edit: happens only after swapping Y and Z by issuing
echo -e keymaps 0-2,4-5,8,12 \\n keycode 21=z \\n keycode 44=y | loadkeys
I am able to unlock the console and continue working with no problems after issuing a reset 2>/dev/tty1
from a ssh session.
I'm even able to issue the reset
from inside the locked console itself using gpm (pressing middle mouse button) when the reset
command is in the gpm buffer.
Reproducible everytime and on any /dev/tty<n>
.
Same effect in VirtualBox versions 4 and 5.
Seems the lock does not occur on the side of VirtualBox because it can be cured on linux's side.
There are no differences in the output of stty -a < /dev/tty1
before and after that reset
.
Other vcs continue to work (chvt issued from ssh), but after Alt+F1 the locked console is still locked: Seems the issue must be located inside the virtual console code.
There are no messages appearing in /var/log/syslog
or dmesg
when that issue happens (when CapsLock pressed). There was one non-reproducible issue that is possibly caused by saving/restoring the VM and might be unrelated:
atkbd serio0: Spurious NAK on isa0060/serio0. Some program might be trying to access hardware directly
in dmesg
.
How can I debug this?
In particular: How can I find the console status difference before and after the reset ?
atkbd serio0
seems to be related:atkbd
is the driver for a PC keyboard, and isa0060 seems to be I/O port 0x60, which is actually the one used by the AT or PS/2 keyboard controller. You might try to switch the virtual machine to a virtual USB keyboard to see if it changes anything. Not sure if there is a GUI option, I did it (in my VM named "Ubuntu") with this command:"c:\Program Files\Oracle\VirtualBox\VBoxManage.exe" modifyvm Ubuntu --keyboard usb
. You might need to adapt it for your VM. If you want to switch back to PS/2 keyboard, replaceusb
withps2
.echo -e keymaps 0-2,4-5,8,12 \\n keycode 21=z \\n keycode 44=y | loadkeys
that I do routinely for my personal keyboard layout.