On Wed, 2010-10-20 at 11:01 -0500, Jason Wessel wrote:

On 10/13/2010 09:34 PM, Maxim Levitsky wrote:

quoted

Nope, still same problem.
Maybe more keys were released, but still
pressing Alt+SysRQ+g second time doesn't break to the debugger.

  

Thanks for trying this out Maxim.

I have to wonder if part of the problem is the way that raw events can
propagate directly via the old keyboard interface vs the input layer.  
I had noticed something somewhat similar with an xorg.conf which
appeared to be using both the raw keyboard and the input layer for
input.  I was having all sorts of problems until I changed the xorg.conf
settings to use the input layer.  I noticed that even pressing the up
arrow in an xterm was invoking the screen shot mechanism for example.

Perhaps you can provide some more data to see if this is a similar
problem or not.

Jardon, I already found the root cause of the problem.
First of all, note that I use xorg's evdev driver.
The in-kernel tty kbd driver is only used for virtual consoles.

The root cause is that in-kernel kbd driver beeing a client of the input
subsystem just doesn't see the sysrq keys because they are filtered,
therefore it can't release them.

The right solution is to somehow hook at the atkbd driver , tell it that
kbd tampered with its hardware, and make it release the keys.

But that is easy to say, not that easy to do...

the in-kernel kbd driver just isn't the right place for the job.

Best regards,
	Maxim Levitsky