system.map, what's it good for?

stabu · 10-06-2005, 02:59 AM

ok, so linux boots up with the kernel image (usually, vmlinuz or zImage or bzImage, whatever ...) but the file system.map is also invoked.

So what the hell does that do? Does anybody have a clear idea?

Pre-empt: "well, it gives the kernel a map of the system". Fine but why's that necessary?

BroX · 10-06-2005, 03:04 AM

See here, for example:
http://www.dirac.org/linux/system.map/

syg00 · 10-06-2005, 04:03 AM

Search first then ask.
If there are things that you have investigated and don't understand, someone will probably be able to help.

*YES*, surprisingly to you maybe, you are not the first to ask ...

stabu · 10-06-2005, 04:34 AM

I have to take issue with your reply syg00. I do so with a high level of respect, I have seen some of your replies to other questions, and they're good stuff, so I don't like to criticise you.

However I'm also a heavy user of the search function, and though I come across relevant posts, many tend to be recipes for solving rather than explanations of the situation.

With my system.map question I ran a search for "system.map", and yes, I got a large number of threads. I consulted one or two of them, and the "clear idea" which I was looking for didn't surface.

I may have found the dirac page on google. I admit I didn't google. It's true that for linux I prefer to use the LQ search, and I stopped there. In any case, the dirac page does say, after all, that

Quote:

There seems to be a dearth of information about the System.map file. It's really nothing mysterious, and in the scheme of things, it's really not that important. But a lack of documentation makes it shady. It's like an earlobe; we all have one, but nobody really knows why.

So I don't think my opening a new post in this subject really merits the patronising so evident in you post.

I would have accepted "you could have looked a little harder", yes. But that reply was really pretty harsh.

syg00 · 10-06-2005, 05:10 AM

Quote:

Originally posted by stabu
I have to take issue with your reply syg00.
...
But that reply was really pretty harsh.

Accepted - with, I hope, the requisite humility.
I know I've responded to this in the past here on LQ. A quick search or two also failed to extract an easily identified definitive post.

Sorry ...
The offer stands - if you still have questions ask away, although I personally think that's a pretty good link.

stabu · 10-06-2005, 12:23 PM

accepted with thanks.

LJSBrokken, thx4link. Great but small site. Wanted to do something similar to that myself, now if I could just grab a bit of time ....

BroX · 10-07-2005, 03:01 AM

Quote:

Originally posted by stabu
accepted with thanks.

LJSBrokken, thx4link. Great but small site. Wanted to do something similar to that myself, now if I could just grab a bit of time ....

I searched for info on System.map myself a while ago and also found that there isn't a lot available. I found a bit more extensive source than the link above (but similar anyways) but I didn't bookmark it. I'll check my documentation at home and post back if I come up with something relevant.

Cheers, Leon.

foo_bar_foo · 10-07-2005, 07:31 PM

to cut throuugh the please and thank yous and the you didn't ask right.

System.map just containt some debugging information and doesn't do crap.