Re: inconsistent kallsyms data [2.6.11-mm2]

From: Paulo Marques
Date: Wed Mar 09 2005 - 16:19:50 EST

Paulo Marques wrote:
Can you send me privately a tar.bz2 containing your .config, .tmp_kallsyms1.S and .tmp_kallsyms2.S so I can try to figure out what's going on?

Ok, after some investigation into the files I was able to find out the problem.

scripts/kallsyms.c uses a subset of the symbol table to optimize the tokens to use to compress the symbols. It does this because using the complete set of symbols would be much slower without a significant gain in compression.

For some reason, in the files sent by Dominik, two aliased symbols change places from the first to the second step of the kallsyms build process (__sched_text_start, __down).

Because of this, the subset used for optimization is different and so are the tokens selected, producing a 2 byte difference in the total size of the compressed symbol names :P

So I must change the sampling algorithm in a way that is robust to symbol position changes.

A simple and robust way is to do the sampling on a list of symbols sorted by symbol name. This way, even if the symbol positions that are given to scripts/kallsyms change, the symbols sampled will be the same.

I'll do the patch to do this and send it ASAP.

Paulo Marques -

All that is necessary for the triumph of evil is that good men do nothing.
Edmund Burke (1729 - 1797)
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at