New debug kernel installation mechanism committed to HEAD

Richard Nyberg rnyberg at
Thu Oct 21 00:59:36 PDT 2004

At Thu, 21 Oct 2004 01:59:13 -0400,
Andrew Atrens wrote:
> Btw, is there a how-to somewhere on how one would load a kernel module
> into gdb to do post-mortem on a vmcore? If one can't do this, then having
> debug info in modules would definitely be less useful.

Yes. See the FreeBSD developer handbook.
Section 11.7 in particular.

> Should this work? -
> gdb -k kernel.0 vmcore.0
> gdb> add-symbol-file /nvidia.ko 0xc060d000
> gdb> bt

I do this on a regular basis:
gdb -k kernel.debug vmcore.9

follow this chain to get the address of my module

objdump --headers /usr/arla/bin/nnpfs.ko | grep text
to see the relocation address.

add address and relocation address

add-symbol-file /usr/arla/bin/nnpfs.ko sum-of-addresses



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