From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 14E1AC43381 for ; Tue, 12 Mar 2019 01:28:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DEFC2214D8 for ; Tue, 12 Mar 2019 01:28:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726689AbfCLB2b (ORCPT ); Mon, 11 Mar 2019 21:28:31 -0400 Received: from mail.kernel.org ([198.145.29.99]:55256 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725932AbfCLB2a (ORCPT ); Mon, 11 Mar 2019 21:28:30 -0400 Received: from oasis.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7BF922084F; Tue, 12 Mar 2019 01:28:26 +0000 (UTC) Date: Mon, 11 Mar 2019 21:28:23 -0400 From: Steven Rostedt To: Joel Fernandes Cc: Daniel Colascione , Karim Yaghmour , Geert Uytterhoeven , Greg KH , LKML , Andrew Morton , Alexei Starovoitov , atish patra , Dan Williams , Dietmar Eggemann , Guenter Roeck , Jonathan Corbet , Kees Cook , Android Kernel Team , "open list:DOCUMENTATION" , "open list:KERNEL SELFTEST FRAMEWORK" , linux-trace-devel@vger.kernel.org, Manoj Rao , Masahiro Yamada , Masami Hiramatsu , Qais Yousef , Randy Dunlap , Shuah Khan , Yonghong Song Subject: Re: [PATCH v4 1/2] Provide in-kernel headers for making it easy to extend the kernel Message-ID: <20190311212823.60684182@oasis.local.home> In-Reply-To: <20190312003912.GA170478@google.com> References: <20190308140251.GC25768@kroah.com> <20190309071648.GE3882@kroah.com> <20190309121141.GA30173@kroah.com> <3e84e1ef-e266-e983-5874-6c26ac7f38b8@opersys.com> <20190311193612.4f09bf11@oasis.local.home> <20190312003912.GA170478@google.com> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 11 Mar 2019 20:39:12 -0400 Joel Fernandes 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