From patchwork Wed Sep 8 14:58:47 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mauro Carvalho Chehab X-Patchwork-Id: 12481295 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=-14.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 4E385C433FE for ; Wed, 8 Sep 2021 14:59:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 39A5C60E77 for ; Wed, 8 Sep 2021 14:59:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1351962AbhIHPAM (ORCPT ); Wed, 8 Sep 2021 11:00:12 -0400 Received: from mail.kernel.org ([198.145.29.99]:59212 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1351932AbhIHPAL (ORCPT ); Wed, 8 Sep 2021 11:00:11 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 831A661163; Wed, 8 Sep 2021 14:59:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1631113142; bh=iER6cNpcjgk8n1TWkifigpXyj5UmGCift9D4uF2jMns=; h=From:To:Cc:Subject:Date:From; b=jEUUiYNesrwxixTuVWUx37ompZysIA5p0KCoiioN0f2BlrS+efomxgByiawC6Jjl8 PfASkEjlfK7hzn3PNaz05R+fyf9GRreUV4a7BzTb9ouOrpuHon2nuQvF1WY/NNgHmC 4t4sQQQX0l/0beJPHdHfx/wbrDWugLr74aLeNc3pPp2boRHSfLPcda06Vfzz/bPVkP STfQDLJpguHWxcT/MVZBintfsTiKoFKXdekzRbOzF+JA36vlO4oBOHqfVXsVVkX30W 3j2HjgCY9z6S4nOOWu7yrTZmsviG4hwOnZf1Xez8C06XGSDDbZzBtD7v0995qNdA82 mmKlHGuSQkIxQ== Received: by mail.kernel.org with local (Exim 4.94.2) (envelope-from ) id 1mNz2S-006r3a-E3; Wed, 08 Sep 2021 16:59:00 +0200 From: Mauro Carvalho Chehab To: Linux Doc Mailing List , Greg KH Cc: Mauro Carvalho Chehab , linux-kernel@vger.kernel.org, Jonathan Corbet , Anton Vorontsov , Colin Cross , John Fastabend , KP Singh , Kees Cook , Martin KaFai Lau , Song Liu , Tony Luck , Yonghong Song , bpf@vger.kernel.org, netdev@vger.kernel.org Subject: [PATCH 0/9] get_abi.pl: Check for missing symbols at the ABI specs Date: Wed, 8 Sep 2021 16:58:47 +0200 Message-Id: X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 Sender: Mauro Carvalho Chehab Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Hi Greg, Sometime ago, I discussed with Jonathan Cameron about providing a way check that the ABI documentation is incomplete. While it would be doable to validate the ABI by searching __ATTR and similar macros around the driver, this would probably be very complex and would take a while to parse. So, I ended by implementing a new feature at scripts/get_abi.pl which does a check on the sysfs contents of a running system: it reads everything under /sys and reads the entire ABI from Documentation/ABI. It then warns for symbols that weren't found, optionally showing possible candidates that might be misdefined. I opted to place it on 3 patches: The first patch adds the basic logic. It runs really quicky (up to 2 seconds), but it doesn't use sysfs softlinks. Patch 2 adds support for also parsing softlinks. It slows the logic, with now takes ~40 seconds to run on my desktop (and ~23 seconds on a HiKey970 ARM board). There are space there for performance improvements, by using a more sophisticated algorithm, at the expense of making the code harder to understand. I ended opting to use a simple implementation for now, as ~40 seconds sounds acceptable on my eyes. Patch 3 adds an optional parameter to allow filtering the results using a regex given by the user. One of the problems with the current ABI definitions is that several symbols define wildcards, on non-standard ways. The more commonly wildcards used there are: {foo} [foo] X Y Z /.../ The script converts the above wildcards into (somewhat relaxed) regexes. There's one place using "(some description)". This one is harder to parse, as parenthesis are used by the parsing regexes. As this happens only on one file, patch 4 addresses such case. Patch 5 to 9 fix some other ABI troubles I identified. In long term, perhaps the better would be to just use regex on What: fields, as this would avoid extra heuristics at get_abi.pl, but this is OOT from this patch, and would mean a large number of changes. - As reference, I sent an early implementation of this change as a RFC: https://lore.kernel.org/lkml/cover.1624014140.git.mchehab+huawei@kernel.org/ Mauro Carvalho Chehab (9): scripts: get_abi.pl: Check for missing symbols at the ABI specs scripts: get_abi.pl: detect softlinks scripts: get_abi.pl: add an option to filter undefined results ABI: sysfs-bus-usb: better document variable argument ABI: sysfs-module: better document module name parameter ABI: sysfs-tty: better document module name parameter ABI: sysfs-kernel-slab: use a wildcard for the cache name ABI: security: fix location for evm and ima_policy ABI: sysfs-module: document initstate Documentation/ABI/stable/sysfs-module | 10 +- Documentation/ABI/testing/evm | 4 +- Documentation/ABI/testing/ima_policy | 2 +- Documentation/ABI/testing/sysfs-bus-usb | 16 +- Documentation/ABI/testing/sysfs-kernel-slab | 94 ++++----- Documentation/ABI/testing/sysfs-module | 7 + Documentation/ABI/testing/sysfs-tty | 32 +-- scripts/get_abi.pl | 218 +++++++++++++++++++- 8 files changed, 303 insertions(+), 80 deletions(-)