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=-3.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_NEOMUTT 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 93AD8C43381 for ; Fri, 15 Feb 2019 03:19:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5F02A21A80 for ; Fri, 15 Feb 2019 03:19:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="vNmOtYWy" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388066AbfBODTg (ORCPT ); Thu, 14 Feb 2019 22:19:36 -0500 Received: from mail-pl1-f196.google.com ([209.85.214.196]:45214 "EHLO mail-pl1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726010AbfBODTg (ORCPT ); Thu, 14 Feb 2019 22:19:36 -0500 Received: by mail-pl1-f196.google.com with SMTP id r14so4205151pls.12; Thu, 14 Feb 2019 19:19:35 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=FbnulF0jYkkLdvSRbeWLpsBAJiFxm/n1FMDU160K/J4=; b=vNmOtYWyWil7fBY++iqOIGnFec3KIbYkCb6gI2q9aA6nvrrt2DjXd5Qd5YzOAkHD8z OxNjEY5BGc+zXlXJiNyjyULA3CucOa8wh5PvYRKfdr8DM7COyc6OcwdV08JKZAMy0Zfu 3AawsjGc+/ji+ZbkSQ81wOhQztqpNKssrQAauCw2nEf5SewqKvDAc/UZPCJWpec2CYb8 ms5EfZnU3PwlnJxJhHGMip5Vqh4YIUvocuIJ6CyiPbqjZHlTS4wjrep/6ZISAtqsc768 7sW7CpCf+y7RhqQAacb6PZHoqLxet/8DGCHlRkYqFl5Ja0YL0TJ5bq5tVcRLAEMhQmP9 R60Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=FbnulF0jYkkLdvSRbeWLpsBAJiFxm/n1FMDU160K/J4=; b=UU42gBsFWTejB9RcXrMRgTrcijSDZRSH5jXbqcBuutaW7uK5WGl1ojN7skfZxYOr78 Cjr9wf1Mx8D0BOV0nQ9Ul1BjUTyyPjUzrxO50K1qTIeOUDr5BaFbcc6hG8Jz6sQLgA2B +ZmREPYlSWHdafp4CXQJcH/q3ys2zDfcqOhNHti52M1b5Tw03YGGGa/0XkZLH7Rzg8av vP8uzJ6Ux9LI8VLbqw23LczAurAefJFnYCFFmhZ6AqnqzRuOSIvlikH5Yo4dEry/zELU sa64vEzXR3J4Hesx0cdjT45FkfRWRSx8lzG7/KaaHqibuHR6FiSJxEPhP0pz9WYZl4Mf K67Q== X-Gm-Message-State: AHQUAubI+j/myeCJcYyKxGZHMF1zXsllfeJqGhJYJdULUDJyYGXc7dzB DQpL1to/KkNpQFmhldXL5mX8w/FFUYo= X-Google-Smtp-Source: AHgI3IaIUiSFmlQXmcQoDfl/viMUGBEdE1F49jS/kB2+TLe832J1EeKzLimXLiD7CLcjdh60fywzWg== X-Received: by 2002:a17:902:758f:: with SMTP id j15mr7681037pll.170.1550200775392; Thu, 14 Feb 2019 19:19:35 -0800 (PST) Received: from ast-mbp ([2620:10d:c090:180::1:b114]) by smtp.gmail.com with ESMTPSA id x23sm9913931pfe.0.2019.02.14.19.19.30 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 14 Feb 2019 19:19:34 -0800 (PST) Date: Thu, 14 Feb 2019 19:19:29 -0800 From: Alexei Starovoitov To: "Joel Fernandes (Google)" Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Andrew Morton , ast@kernel.org, atishp04@gmail.com, dancol@google.com, Dan Williams , gregkh@linuxfoundation.org, Jonathan Corbet , karim.yaghmour@opersys.com, Kees Cook , kernel-team@android.com, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, Manoj Rao , Masahiro Yamada , paulmck@linux.vnet.ibm.com, "Peter Zijlstra (Intel)" , rdunlap@infradead.org, rostedt@goodmis.org, Shuah Khan , Thomas Gleixner , yhs@fb.com Subject: Re: [PATCH v2 1/2] Provide in-kernel headers for making it easy to extend the kernel Message-ID: <20190215031926.ljzluy2cfxp64u6o@ast-mbp> References: <20190211143600.15021-1-joel@joelfernandes.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190211143600.15021-1-joel@joelfernandes.org> User-Agent: NeoMutt/20180223 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Feb 11, 2019 at 09:35:59AM -0500, Joel Fernandes (Google) wrote: > Introduce in-kernel headers and other artifacts which are made available > as an archive through proc (/proc/kheaders.txz file). This archive makes > it possible to build kernel modules, run eBPF programs, and other > tracing programs that need to extend the kernel for tracing purposes > without any dependency on the file system having headers and build > artifacts. > > On Android and embedded systems, it is common to switch kernels but not > have kernel headers available on the file system. Raw kernel headers > also cannot be copied into the filesystem like they can be on other > distros, due to licensing and other issues. There's no linux-headers > package on Android. Further once a different kernel is booted, any > headers stored on the file system will no longer be useful. By storing > the headers as a compressed archive within the kernel, we can avoid these > issues that have been a hindrance for a long time. The set looks good to me and since the main use case is building bpf progs I can route it via bpf-next tree if there are no objections. Masahiro, could you please ack it?