Status of kernel marker support

David Smith dsmith@redhat.com
Tue Oct 2 21:06:00 GMT 2007


Mathieu Desnoyers wrote:

> The best is to get the latest marker post I made on LKML, posted back
> Fri, 28 Sep 2007 10:28:45. However, since you don't have the full
> patchset to be merged in the -mm tree, it is probably best for me to
> prepare a tarball. Here it is:
> http://ltt.polymtl.ca/markers/markers-patches-for-2.6.23-rc8-mm2-02-10-2007.tar.bz2

Thanks for the tarball - I've been downloading the patches from a lkml 
web archive today and there were a bit mangled so this will help.

> Please keep in mind that it will break the tools you have, which depends
> on the __markers_strings section to be a "real" section, not just a blob
> of data.
> 
> In order to get the markers from the kernel image, you should use the
> __start___markers and __stop___markers symbols. (since the __markers
> section is packed in the .data section in the linker scripts, I think
> __markers will just vanish) (see include/asm-generic/vmlinux.lds.h for
> details).
> 
> To get the markers from the kernel modules, using the __markers sections
> seems like a good solution.

I figured the removal of the __markers_string section was coming, so 
I've been trying to look into this.

I've certainly seen that distinction in the 9/18 patch set - the main 
kernel has the __markers section packed in the .data section (surrounded 
by __start___markers and __stop___markers) but kernel modules have a 
distinct __markers section.

Out of curiosity, was there a particular reason for the two different 
methods or did it just work out that way?

-- 
David Smith
dsmith@redhat.com
Red Hat
http://www.redhat.com
256.217.0141 (direct)
256.837.0057 (fax)



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