6.1-PRE boot locks up, using USB keyboard

[Rick C. Petty]

On Wed, Mar 15, 2006 at 12:27:08PM -0500, John Baldwin wrote:
> On Wednesday 15 March 2006 12:11, Rick C. Petty wrote:
> > 
> > My BIOS (Asus A8N-E rev 1010) has no option for disabling USB keyboard
> > support, but I can either disable the USB controller or disable the USB
> > legacy support.  I doubt either of these is desirable.  Fortunately, I
> > discovered the problem..
> 
> The "legacy support" option is the one that makes a USB keyboard look like
> a PS/2 keyboard.

If I disable legacy support, the USB keyboard is useless until the kernel
comes up multi-user and usbd is started, as I expected.  Other than that,
everything behaves identically.

> > Whenever ukbd is loaded by /boot/loader and that
> > device already exists in the kernel, the boot locks up after:
> > 
> > atkbdc0: <Keyboard controller (i8042)> at port 0x60,0x64 on isa0
> > 
> > when using a USB keyboard.  I would think this is a bug.  It is 100%
> > repeatable for me.  If I comment out the line in /boot/loader.conf, the
> > system boots nicely.
> 
> Ok.  There are several edge cases that can blow up if you kldload a module
> or load a module from the loader that is already present in the kernel.

I would think the loader or the kernel should be smart enough not to
break when loading an already-loaded module.  Is there a workaround?
If not, all kernels must be compiled with ukbd (if they are to support
USB keyboards in single-user mode, e.g.).  There should also be a
warning "BEWARE: Do not set ukbd_load in your loader.conf"  :-P

Seriously, though, the kernel should not break when loading an unloaded
module.  I first noticed this whenever I had umass(4) in the kernel and
it wouldn't detect my USB memory stick but then kldload'd it, saw "File
exists", but then it would be detected.  I remember removing umass from
my config and it behaving quite differently.  I never had time to pursue
that problem.  

-- Rick C. Petty