Keep on getting segmentation fault when trying to load linice

[tiger_claw2000]

I currently run RHEL 4 AS and I keep on getting segmentation fault when
trying to
lod linice.o with linsym. I use the following command

./linsym -i -v 3 -m /boot/System.map

Anybody have any ideas

[Zaphod Beeblebrox]

Hey;

Actually, yeah..I had the same issue but I think that I managed to
track it down.

1. first thing: what kernel version are you using? ( I read that the
2.6x isn't supported)
2. also, I got frustrated and used ddd ( are you familiar with it??) It
was showing me 2 things:
a) linsym wasn't reading my System.map but it looks as if you have that
covered.
b) also, it wasn't finding the linice.o module.

To fix this, I rebuilt linice in the /usr/src directory . It created
the ../linice/bin/linux<kernel_ver>/linice.o . The output of my
debugger ( DDD) was showing me that linsym was not finding the module.
So, I set the env variable LINSYM=/usr/src/linice/bin and ran linsym
-i -v 3 and it loaded.

Now, I just cannot translate symbols...that is my next hurdle...

Cheers

Z

[Goran Devic]

Hi,
Besides the configurations not supported for which you already know of
(kernels above 2.6.8), Linice cannot handle 4GB option which is
sometimes built with RH distros. You can see if your kernel is using it
if your System.map contains very low addresses (not 80000000 or
C0000000). Could that be the problem with your RHEL 4 AS?

Zaphod, it seems like you nailed your problem (b) by using the env.
variable. I am suprised you had to move it to /usr/src directory - that
should not be necessary, but I can't tell about your particular setup.

How about (a)? There is a simple way Linsym arrives to the idea on what
is the exact name of System.map. That could probably be improved.
Anyhow, if you use the option -m to the Linsym to specify the full path
and name of your version of System.map file, that should fix it.

Regards,
- Goran

[Mario Schallner]

hi goran,

thanks for that little summary! i did not know why it did not work on my
prev mdk, it displayed syms at C0000000, and i did not find a hint in the
docu?
now actually under debian i must grab a 2.6.8 kernel to get it work i see.

thx, mario

[Goran Devic]

Hi,
I dont know if I understood your reply correctly - If it displayed
symbols at C0000000, that would be ok:

This is from Debian, working just fine:
c0100000 A _text
c0100000 T startup_32
c01000c6 t checkCPUtype

This is from FedoraCore2 - definitely NOT working:
021474e9 T I_BDEV
022b6c6c r __ksymtab_I_BDEV
022bc786 r __kstrtab_I_BDEV

so if mdk displayed syms at C0000000+ there must be something else
with it. What mdk distro did you use?

thanks,
- Goran

[Mario Schallner]

hi,

it was mandrake 10.0, but I do not have it anymore. Was on an old laptop
now I am using debian, so I can not tell you :( :)

Btw I never had success to run linice on mandrake I remember using kernel
2.4.x, 2.6.y (x,y i do not remember anymore).
I got it compiling and I think linice 2.5 compiled without making any
changes, also System.map and all prerequisites I took care of. Strange it
always hung when loading with linsym. I recompiled the kernel quite often
using several combinations of debugging symbols, features on and off, ACPI
on off, ... But this is just historical for me now.

cheers, ms

[Goran Devic]

yeah, it is really difficult to tell what is going on with individual
problems, especially with recompiled kernels... Most of the time I can
only post common pitfalls and copy what people tell me the problem
was... If it were simple, we would not be doing it for fun :)

cheers