From owner-freebsd-hackers@FreeBSD.ORG  Sat Oct  7 09:01:55 2006
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From: Hans Petter Selasky <hselasky@c2i.net>
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Date: Sat, 7 Oct 2006 11:02:12 +0200
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Subject: Keyboard system and Giant
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Hi,

Does someone here have the overview over the keyboard system?

I see that at least printf calls into the keyboard system without holding 
Giant, which did cause a panic in the new USB keyboard driver. This happens 
when the kernel prints text to the screen in text-mode, and printf wants to 
turn off the scroll lock led.

Now I have found a second place where the keyboard system is called without 
Giant, and this happens when I switch from X11 to text-mode using CTRL+ALT+F1 
for example. Then I get a panic, but I cannot see where. Does someone here 
understand that process?

What should I do?

Should I just lock Giant in ukbd if it is not locked already? This might cause 
locking order reversals.

The obvious solution to me is to get the keyboard layer out of Giant. Is 
anyone working on that?

--HPS