DomainKey-Signature: a=rsa-sha1; c=nofws;
        d=gmail.com; s=gamma;
        h=mime-version:in-reply-to:references:date:message-id:subject:from:to
         :cc:content-type:content-transfer-encoding;
        b=ZxwJLV75D8nfFWM3j0VFcq79Ky1owywItJgEJ454/PKd0+lwPYe3VXMtwUvoKQJRS2
         39T4wf/1/0DYVzaIqLbjILfTuJFK4iYL78OkyRls4apie93uunO2JQ3G1WF7o8qx6ipH
         ezZu2yBuBE7yfxKtT2rsxBouWLFVD1gr00MJg=
MIME-Version: 1.0
In-Reply-To: <20090122133107.GA27592@sgi.com>
References: <4104961b0901220259u51677cbdkda2ed84dc2892543@mail.gmail.com>
	 <20090122133107.GA27592@sgi.com>
Date: Fri, 23 Jan 2009 14:37:12 +0800
Message-ID: <4104961b0901222237h7fac5b1vf1b3b7f9d06d550c@mail.gmail.com>
Subject: Re: How to generate a Kerntypes file?
From: jidong xiao <jidong.xiao@gmail.com>
To: Cliff Wickman <cpw@sgi.com>
Cc: linux-kernel@vger.kernel.org
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 3690
Lines: 99

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
>
--
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/