Messages in this thread | | | Date | Fri, 23 Jan 2009 14:37:12 +0800 | Subject | Re: How to generate a Kerntypes file? | From | jidong xiao <> |
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On Thu, Jan 22, 2009 at 9:31 PM, Cliff Wickman <cpw@sgi.com> wrote: > Hi Jason, > > On Thu, Jan 22, 2009 at 06:59:34PM +0800, jidong xiao wrote: >> Hi,All, >> >> Sometimes when I install a kernel I saw there is a Kerntypes file >> installed under /boot directory, but sometimes no, I remember when I >> install a sles9 kernel, there must be a Kerntypes file installed, but >> most of other kernels doesn't include such a Kerntypes file. This file >> is very useful for me to do some analysis, so I hope I can generate it >> every time I build a kernel. Do I need a patch for this or there are >> already some patches I can take use of?Thanks. > > You had a init/kerntypes.c in sles9 and sles10. It included a lot > of basic kernel types. It was compiled with -g to make the kerntypes. > I presume that you used the LKCD project's lcrash with the kerntypes. > Hi, Cliff,
Thanks for your guides.
Well yes I am intending to use lcrash to load the kernel debug information.
I noticed that recently kdb is going to be able to print out kernel structures, and now I want to test that feature, I started my experiments by reading the instructions inside kdb/modules/kdbm_debugtypes.c which is saying:
* Usage: * in order for the insmod kdbm_debugtypes.ko to succeed in loading types * you must first use lcrash -t kerntypes.xxxx -o debug_info * and echo debug_info > /proc/kdb/debug_info_name
so I have to generate kerntypes file. I looked into init/kerntypes.c, it seems there is nothing but just includes some header files, like below:
16 #include <linux/compile.h> 17 #include <linux/module.h> 18 #include <linux/mm.h> 19 #include <linux/vmalloc.h> 20 #include <linux/config.h> 21 #include <linux/utsname.h> 22 #include <linux/kernel_stat.h> 23 #include <linux/dump.h> 24 25 #include <asm/kerntypes.h>
We can see here are 9 files are included, does this mean the resulted Kerntypes file only provides kernel structures that are defined within these 9 files? If I want to print out more kernel structures I need to change this file so as to include more header files?
In addition, if I want to generate Kerntypes file via building a mainline kernel(rather than SLES kernel), the only thing I need to do is: 1. add this init/kerntypes.c and include/asm/kerntypes.h into kernel source code. 2. change the Makefile accordingly.
After that I just compile the kernel as usual and I should be able to get the Kerntypes file(which is actually nothing but just init/kerntypes.o), right?
Regards Jason
> If you download lkcd (lkcd.svn.sourceforge.net) you also build a > tool called dwarfextract. It is able to pull all the structure > definitions out of a -g (CONFIG_DEBUG_INFO) kernel and any selected > modules. That is useful with the lcrash command. > > If you want to analyze your live system or a dump with the crash command > (people.redhat.com/~anderson/) you don't need the kerntypes, as you use > the -g kernel itself. Although you may make kerntypes with dwarfextract > and use them with crash also. > > -Cliff > >> Regards >> Jason >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> Please read the FAQ at http://www.tux.org/lkml/ > > -- > Cliff Wickman > Silicon Graphics, Inc. > cpw@sgi.com > (651) 683-3824 >
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