temporary freezes when pressing capslock / numlock

[Jeremy Chadwick]

On Sat, May 24, 2008 at 01:38:08PM +1000, Fraser Tweedale wrote:
> Since upgrading to RELENG_7_0 I was experiencing momentary freezes (of 
> about .5 seconds) whenever the capslock or numlock buttons were pressed.

Let me guess -- you're using a USB keyboard.

> The issue occurs both in console and in X, and for both ULE and 4BSD. The 
> problem was reproducible with USB keyboards only (ukbd); atkbd seems fine.  
> It also occurs when numlockx is used to set numlock on or off without 
> keyboard interaction.

I figured as much.  I hadn't checked numlock/capslock myself, but vcons
switching also has that problem.  Yes, it's semi-documented; see section
"USB" below:

http://wiki.freebsd.org/JeremyChadwick/Commonly_reported_issues

For what it's worth, the systems I've confirmed the problem on are Intel
and nForce 4.  Meaning, the issue is not specific to a single chipset.

> Interestingly, if you add enough keyboards, the problem vanishes, which led 
> me to kbdmux.  Sure enough, removing device kbdmux from the kernel makes 
> the problem go away (at the expensive of some functionality of course, but 
> this is my current workaround).

An interesting find!  I'll add this to the details in the above wiki.
I've also CC'd kbdmux's maintainer.

-- 
| Jeremy Chadwick                                jdc at parodius.com |
| Parodius Networking                       http://www.parodius.com/ |
| UNIX Systems Administrator                  Mountain View, CA, USA |
| Making life hard for others since 1977.              PGP: 4BD6C0CB |