re: line numbers in debugging kernel module

[matthew green <mrg%eterna23.net@localhost>]

Beesdeckar writes:
> Hello,
> I build kernel module with these line in Makefile:
> CFLAGS:=$(CFLAGS) -DDEBUG -DMKDEBUG=yes -DMKCTF=yes -Wno-multichar -O0 -g
>
> and when I loaded crash dump into gdb and use
> add-symbol-file path_to_module.kmod <address of .text>
>
> then after bt I see function names but not line numbers.
> I tried to switch off CTF with -DMKCTF=no, add -gdwarf-4 and another 
> variants, still I have no line numbers and I dont see section named .debug.
> when I use compiler switch -v still I am seeing that ctfconvert is 
> called on every compiled object file.
>
> How to change Makefile to see line numbers in gdb ?

with MKDEBUG=yes, your kernel module has it's debug info moved into
a separate file -- in a ".debug" file, and there should be a link
in the original for where it is expected to me installed.  put it
there, and i bet gdb works..

eg, random example on my host:

-r--r--r--  1 root  wheel  24072 Nov 12 00:17 /stand/amd64/11.99.3/modules/scmd/scmd.kmod
-r--r--r--  1 root  wheel  81496 Nov 12 00:17 /usr/libdata/debug/stand/amd64/11.99.3/modules/scmd/scmd.kmod.debug

try that.


.mrg.