kernel debugger and usb keyboard

[Marcel Moolenaar]

On Jul 16, 2009, at 1:43 AM, Alexander Best wrote:
> modern bioses support an option called legcy usb keyboard support.  
> the way i
> understood it is that the bios grabs usb keyboard events and uses  
> them to
> emulate an AT keyboard. that way e.g. a bootloader can the used   
> with a usb
> keyboard although there's no usb stack or whatever in the bootloader.
>
> when the kernel boots the usb stack takes control over the usb  
> keyboard and
> the bios keyboard legacy support gets disabled. couldn't we revert  
> to this
> stage after a panic occurs? letting the bios take control over the usb
> keyboard again and emulate an AT keyboard?

This obviously doesn't apply to hardware that isn't PC hardware.
The USB stack is generic code and you cannot assume some PC BIOS
is there to handle things.

FYI,

-- 
Marcel Moolenaar
xcllnt at mac.com