From patchwork Tue Aug 2 17:39:13 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Paul E. McKenney" X-Patchwork-Id: 12934924 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BF30EC19F29 for ; Tue, 2 Aug 2022 17:39:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232693AbiHBRjV (ORCPT ); Tue, 2 Aug 2022 13:39:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34242 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229690AbiHBRjS (ORCPT ); Tue, 2 Aug 2022 13:39:18 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C36474B0D8; Tue, 2 Aug 2022 10:39:17 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 6ED02B81FE4; Tue, 2 Aug 2022 17:39:16 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0D039C433C1; Tue, 2 Aug 2022 17:39:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1659461955; bh=MuBLArNMizvUksBhjYtQXr2Fl8QtF7ViTn25ne4X8Jk=; h=From:To:Cc:Subject:Date:From; b=Owrpy1b6JGbxAj+OZKkLPxy84SMEQ1r8CFVtqfWGqJIHRI8+hUaYD2kSOFnJJ3xNf T10k4SF4f3znZHwaWVNdYX9ireXQREz2j4fwh2HXa19OlQJXzjXQg2mG1OU3g647zC jzlhR6iUy/M6xcx1tA+EpYVyfYQqAVs8A0AI85MvXrRA+ogYcJbubMsaBCBXybKPOU 2iQ9CRiH5q64t1R3b4TMM3E+viFyp3iTs3GnjQ2F/Lc14GHScqIxnuFF60DrA49S0u ZlQlbCR/xHkWMsQzKXCjJt/YyhFTFP/s8mz35Q7B7Lzf5iQTH8pvTQMadpcyQz5i4O 0x8YV4/Dc0z3g== Received: by paulmck-ThinkPad-P17-Gen-1.home (Postfix, from userid 1000) id B6AF55C0830; Tue, 2 Aug 2022 10:39:14 -0700 (PDT) From: "Paul E. McKenney" To: bpf@vger.kernel.org, netdev@vger.kernel.org, linux-doc@vger.kernel.org Cc: corbet@lwn.net, ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, kafai@fb.com, songliubraving@fb.com, yhs@fb.com, john.fastabend@gmail.com, kpsingh@kernel.org, kernel-team@fb.com, "Paul E. McKenney" , Alexei Starovoitov Subject: [PATCH v3 bpf 3/3] bpf: Update bpf_design_QA.rst to clarify that BTF_ID does not ABIify a function Date: Tue, 2 Aug 2022 10:39:13 -0700 Message-Id: <20220802173913.4170192-3-paulmck@kernel.org> X-Mailer: git-send-email 2.31.1.189.g2e36527f23 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net This patch updates bpf_design_QA.rst to clarify that mentioning a function to the BTF_ID macro does not make that function become part of the Linux kernel's ABI. Suggested-by: Alexei Starovoitov Signed-off-by: Paul E. McKenney --- Documentation/bpf/bpf_design_QA.rst | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/Documentation/bpf/bpf_design_QA.rst b/Documentation/bpf/bpf_design_QA.rst index a06ae8a828e3d..a210b8a4df005 100644 --- a/Documentation/bpf/bpf_design_QA.rst +++ b/Documentation/bpf/bpf_design_QA.rst @@ -291,3 +291,10 @@ The kernel function prototypes will change, and BPF programs attaching to them will need to change. The BPF compile-once-run-everywhere (CO-RE) should be used in order to make it easier to adapt your BPF programs to different versions of the kernel. + +Q: Marking a function with BTF_ID makes that function an ABI? +------------------------------------------------------------- +A: NO. + +The BTF_ID macro does not cause a function to become part of the ABI +any more than does the EXPORT_SYMBOL_GPL macro.