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Date: Sat, 3 Feb 1996 17:47:21 -0500 (EST)
From: "Marc G. Fournier" <scrappy@ki.net>
To: Joerg Wunsch <joerg_wunsch@uriah.heep.sax.de>
cc: hackers@FreeBSD.ORG
Subject: Re: How to use DDB to debug a boottime panic?
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Okay, I delved into DDB, and came out unscathed, I think...well, at least
I seem to have more info and knowledge then I started, which is a good
thing :)

Using sd(0,a)/kernel -d to get into DDB (several times), I performed the
following:

b ncr_attach + 0x192 (according to handbook, this should work)
   - From Handbook:
	- Simple expressions are allowed, for example: function-name + 0x103.
   - When I tried, it always ran through until it hit the panic *shrug*
	
c
x/x scbus,10 -> Symbol not found

Restarted from the top:

b ncr_attach
c
Breakpoint at _ncr_attach: pushl %ebp
x/x scbus,10 -> Symbol not found
b scsi_attachdevs 
x/x scbus,10 -> Symbol again not found


	So, looking at the ncr.c code:

#if (__FreeBSD__ >= 2)
        struct scsibus_data *scbus;
#endif

	And the fact that I'm using gcc 2.7.2, could this be the problem?
Could I not have __FreeBSD__ set to 2 properly, and therefore its not 
pulling this in?

	With this in mind, I'm going to try to recompile the kernel using
gcc 2.6.3 that came with the OS, and see if that helps.  If this doesn't
look like what the problem is...

	...help :( 

Thanks...

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