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Date:   Mon, 11 Mar 2019 21:28:23 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Joel Fernandes <joel@joelfernandes.org>
Cc:     Daniel Colascione <dancol@google.com>,
        Karim Yaghmour <karim.yaghmour@opersys.com>,
        Geert Uytterhoeven <geert@linux-m68k.org>,
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        Alexei Starovoitov <ast@kernel.org>,
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        Dan Williams <dan.j.williams@intel.com>,
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        Randy Dunlap <rdunlap@infradead.org>,
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Subject: Re: [PATCH v4 1/2] Provide in-kernel headers for making it easy to
 extend the kernel
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On Mon, 11 Mar 2019 20:39:12 -0400
Joel Fernandes <joel@joelfernandes.org> wrote:

> I think even though the kernel-headers can't have information about all data
> structures, they do already contain a lot of data structure definitions we
> need already. And anything needed can/should arguably be moved to include/ if
> they are really needed for kernel extension by something "external" to the
> kernel such as kernel modules or eBPF, right?

That's not my worry. I would like to be able to easily walk data
structures from within the kernel, without having to do a lot of work
in userspace to get that information. The kprobe_events could then be
passed type casts or such to access data fields of arguments to
functions and such.

> 
> In any case, such a solution such as what Steve suggested, still cannot do
> what we can with headers - such as build kernel modules on the fly using the
> C-compiler without any auto-generation of C code from any debug artifiacts.
> Think systemtap working with the module-backend without any need for
> linux-headers package on the file system. So such a solution would still be a
> bit orthogonal in scope to what this proposed solution can solve IMO.
> 

With the information I would like to have, it would be trivial to read
the data to create the header files needed for modules.

-- Steve