Confusing RPI2 kernel options

[bob prohaska]

On Wed, Mar 30, 2016 at 07:01:55PM +0800, Jia-Shiun Li wrote:
> On Wed, Mar 30, 2016 at 3:30 PM, Hans Petter Selasky <hps at selasky.org>
> wrote:
> 
> That's not about keyboard but "boot console",
> or more formally "system console",
> to which kernel messages is output.
> 
> At booting kernel,
> 
> - with vt, kernel boot messages go to HDMI display.
>   Serial port shows nothing until getty is up for it to
>   bring login prompt.
> - without vt, kernel boot messages go to serial port.
> 
> 
> -Jia-Shiun.

That's not what I'm observing. Using a kernel config containing
# Comment following lines for boot console on serial port
device          vt
device          kbdmux
device          ukbd

the serial console gets a complete transcript of the boot process,
but the HDMI display stops updating somewhere around the ethernet
probe and does not resume until a login prompt appears.  Thats the 
reverse of the indicated behavior. 

Has anybody tried commenting out those lines to see what happens?
It would be a pleasant surprise if the USB keyboard started to work
in single-user mode.

Thanks for reading,

bob prohaska