linux-imx/scripts/mksysmap
Sam Ravnborg aab34ac858 kbuild: filter away debug symbols from kernel symbols
Andi Kleen <andi@firstfloor.org>
reported that he saw a lot of symbols like this:

0000000000000b24 N DW.aio.h.903a6d92.2
0000000000000bce N DW.task_io_accounting.h.8d8de327.0
0000000000000bec N DW.hrtimer.h.c23659c6.0

in his System.map / kallsyms output.

Simple solution is to skip all debugging
symbols (they are marked 'N').

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Paulo Marques <pmarques@grupopie.com>
2008-05-19 20:07:58 +02:00

1.3 KiB

#!/bin/sh -x

Based on the vmlinux file create the System.map file

System.map is used by module-init tools and some debugging

tools to retrieve the actual addresses of symbols in the kernel.

Usage

mksysmap vmlinux System.map

Generate System.map (actual filename passed as second argument)

$NM produces the following output:

f0081e80 T alloc_vfsmnt

The second row specify the type of the symbol:

A = Absolute

B = Uninitialised data (.bss)

C = Comon symbol

D = Initialised data

G = Initialised data for small objects

I = Indirect reference to another symbol

N = Debugging symbol

R = Read only

S = Uninitialised data for small objects

T = Text code symbol

U = Undefined symbol

V = Weak symbol

W = Weak symbol

Corresponding small letters are local symbols

For System.map filter away:

a - local absolute symbols

U - undefined global symbols

N - debugging symbols

w - local weak symbols

readprofile starts reading symbols when _stext is found, and

continue until it finds a symbol which is not either of 'T', 't',

'W' or 'w'. _crc are 'A' and placed in the middle

so we just ignore them to let readprofile continue to work.

(At least sparc64 has _crc in the middle).

$NM -n $1 | grep -v '( [aNUw] )|(_crc)|( $[adt])' > $2