Re: debug registers

From: Matt Taylor (para_at_tampabay.rr.com)
Date: 04/29/04 

Date: Thu, 29 Apr 2004 05:51:23 +0000 (UTC)

"Wendy E. McCaughrin" <wemccaug@bluestem.prairienet.org> wrote in message
news:c6p98v$r4$1@wildfire.prairienet.org...
> Can the debug registers (DR0...DR3 for breakpoint, D6,D7) be used to
> monitor another program for a certain instruction to execute? E.g.,
> say I wanted a program to monitor a child process for execution of
> a LIDT instruction: I can do that without the debug regs easily
> enough, but is there a more efficient way with them?

No, not for a specific instruction. The debug registers are for
breakpointing on access to a specific address (execute, read, or
read/write). If the child process is not privileged (as I would assume),
then it will fault and you can use whatever debug mechanism your OS gives
you to watch for that.

-Matt

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