From patchwork Mon Mar 28 21:19:56 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marcelo Schmitt X-Patchwork-Id: 12794256 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 44D8BC433F5 for ; Mon, 28 Mar 2022 21:20:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229550AbiC1VVw (ORCPT ); Mon, 28 Mar 2022 17:21:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54774 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229501AbiC1VVs (ORCPT ); Mon, 28 Mar 2022 17:21:48 -0400 Received: from mail-oi1-x232.google.com (mail-oi1-x232.google.com [IPv6:2607:f8b0:4864:20::232]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8B7BBDE0AA; Mon, 28 Mar 2022 14:20:03 -0700 (PDT) Received: by mail-oi1-x232.google.com with SMTP id 12so17040074oix.12; Mon, 28 Mar 2022 14:20:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=date:from:to:cc:subject:message-id:mime-version:content-disposition; bh=9qRB0II6Ytegh9oDXsqAEWbvdBJG2QMLk1XoynhcSdc=; b=dxqQd6nql5QXzoESlASrLi1QNkobaBAfzSkh02IyFE7xIQp9LayDWrLjad2/e4NV3e xhjRuCUBFwECfaR20P33Z4CpX1MdPjRdQRUuTFiOJFcKXeBjA5r+bizltdaNZWuiSWD6 hn1f33L5SfUYyaf5iJIsYYAl/bx+r9sHzE1xKxI4L2A6dDqoobwqfBGMLODhu52x7k5D QHqWvOHY9zBJ3N9mSrpxkEqkw5dBK70UBub3nxP9Zqnztjjy+jv21M5JKOtmDNr9/cF5 B5PQm8obEdKDAtVCwldxSMJh4cU1a5C9t2Aw6KmO9bB0SAvfuTQvRrz4YjkoE0rpSa29 dRmQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:mime-version :content-disposition; bh=9qRB0II6Ytegh9oDXsqAEWbvdBJG2QMLk1XoynhcSdc=; b=s8CYnYUe04PlkSPi7KP7Uft8PjbZkDdrZVhH4ewb0XBE/6JTiOPtpZNN+ZPDwzVo4K 45fkufdR3Nf3hGd1siHqdE+fp5TF+TUHHNVDtPNM4fEHmhPnRB5k75qfDIU5i6O7Y3QI LRMA91LBPgL9oITDZLE0R3iMjM08s7FYyAp7Ea9waUGqf3uG8/O52DVBCJJN1YLot6eM EY8cUUdSKi9OviR2EKqv+y+b1AZoD4MX7cwO2RaaG4jLJMp2ml6Mjf1eoFAAQKN/Nxp1 7gKrHZ8AjMpDCMgk8XbGfknBNogQjr1BrnnNukWS4phbhj+ZV/uaq4ZUkJzF1TlwzxLo jh+Q== X-Gm-Message-State: AOAM530i+eWTPG2cad6racpyf2hhMyJ2vqhVpDKe+Pm+1bqhK4pGed5J epWyM+4ekCkFXAhLQJITujxjZ1yOdEB/qw== X-Google-Smtp-Source: ABdhPJyfDVaw45zbC+ieRzXi6qjNPLAoCc7QpjVc07EsaBBdS2dXFzBmXSZZyWt4sD5iyArPPUtkew== X-Received: by 2002:aca:705:0:b0:2d9:6bb6:5b0 with SMTP id 5-20020aca0705000000b002d96bb605b0mr621876oih.11.1648502402818; Mon, 28 Mar 2022 14:20:02 -0700 (PDT) Received: from marsc.168.1.7 ([2804:d57:1503:f300:282c:2283:f732:e1c7]) by smtp.gmail.com with ESMTPSA id q9-20020a4ae649000000b00320d35fc91dsm7408930oot.24.2022.03.28.14.19.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 28 Mar 2022 14:20:02 -0700 (PDT) Date: Mon, 28 Mar 2022 18:19:56 -0300 From: Marcelo Schmitt To: corbet@lwn.net, mchehab+huawei@kernel.org, dlatypov@google.com, davidgow@google.com Cc: linux-doc@vger.kernel.org, linux-sparse@vger.kernel.org, cocci@inria.fr, smatch@vger.kernel.org, linux-kernel@vger.kernel.org, skhan@linuxfoundation.org Subject: [PATCH] Documentation: dev-tools: Add a section for static analysis tools Message-ID: MIME-Version: 1.0 Content-Disposition: inline Precedence: bulk List-ID: X-Mailing-List: linux-sparse@vger.kernel.org Complement the Kernel Testing Guide documentation page by adding a section about static analysis tools. Signed-off-by: Marcelo Schmitt Reviewed-by: Shuah Khan Acked-by: Daniel Latypov Reviewed-by: David Gow Acked-by: Dan Carpenter --- Hey everyone, I think this patch can be a good addition to the documentation as discussed in the thread for the testing guide documentation page: Link: https://lore.kernel.org/linux-doc/CABVgOS=2iYtqTVdxwH=mcFpcSuLP4cpJ4s6PKP4Gc-SH6jidgQ@mail.gmail.com/ If you think it would be worth it, I can try making something more elaborated. Maybe provide some guidance on when to use each tool. I've been studying how Linux device drivers are tested. Here's a post I wrote talking about some testing tools. Link: https://marcelosc.gitlab.io/how-is-linux-tested/ Best regards, Marcelo Documentation/dev-tools/testing-overview.rst | 29 ++++++++++++++++++++ 1 file changed, 29 insertions(+) diff --git a/Documentation/dev-tools/testing-overview.rst b/Documentation/dev-tools/testing-overview.rst index 65feb81edb14..b00511109a9d 100644 --- a/Documentation/dev-tools/testing-overview.rst +++ b/Documentation/dev-tools/testing-overview.rst @@ -115,3 +115,32 @@ that none of these errors are occurring during the test. Some of these tools integrate with KUnit or kselftest and will automatically fail tests if an issue is detected. +Static Analysis Tools +====================== + +In addition to testing a running kernel, one may also scout for bugs by +analyzing the source code semantics. Three tools are well known for serving this +purpose. + +Sparse can help test the kernel by performing type-checking, lock checking, +value range checking, in addition to reporting various errors and warnings while +examining the code. See the Documentation/dev-tools/sparse.rst documentation +page for details on how to use it. + +Smatch extends Sparse and provides additional checks for programming logic +mistakes such as missing breaks in switch statements, unused return values on +error checking, forgetting to set an error code in the return of an error path, +etc. Smatch also has tests against more serious issues such as integer +overflows, null pointer dereferences, and memory leaks. See the project page at +http://smatch.sourceforge.net/. + +We also have Coccinelle as an option within static analyzers. Coccinelle is +often used to aid collateral evolution of source code, but it can also help to +avoid certain bugs that have been expressed semantically. The types of tests +available include API tests, tests for correct usage of kernel iterators, checks +for the soundness of free operations, analysis of locking behavior, and further +tests known to help keep consistent kernel usage. See the +Documentation/dev-tools/coccinelle.rst documentation page for details. + +These static analysis tools support running tests on the whole source tree or +over a specific file or directory.