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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 63BE2C4743C for ; Wed, 23 Jun 2021 14:26:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 49D036112D for ; Wed, 23 Jun 2021 14:26:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230430AbhFWO2a (ORCPT ); Wed, 23 Jun 2021 10:28:30 -0400 Received: from vmicros1.altlinux.org ([194.107.17.57]:35116 "EHLO vmicros1.altlinux.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230061AbhFWO22 (ORCPT ); Wed, 23 Jun 2021 10:28:28 -0400 Received: from imap.altlinux.org (imap.altlinux.org [194.107.17.38]) by vmicros1.altlinux.org (Postfix) with ESMTP id A8AE272C8B4; Wed, 23 Jun 2021 17:26:08 +0300 (MSK) Received: from altlinux.org (sole.flsd.net [185.75.180.6]) by imap.altlinux.org (Postfix) with ESMTPSA id 90E904A46EC; Wed, 23 Jun 2021 17:26:08 +0300 (MSK) Date: Wed, 23 Jun 2021 17:26:08 +0300 From: Vitaly Chikunov To: Shuah Khan , linux-kselftest@vger.kernel.org Cc: "Dmitry V. Levin" Subject: Kernel selftests and backward compatibility? Message-ID: <20210623142608.xx6qc3mkzc72z2cr@altlinux.org> MIME-Version: 1.0 Content-Type: text/plain; charset=koi8-r Content-Disposition: inline Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Shuah, Do kselftests require to be backward-compatible? I see Documentation/dev-tools/kselftest.rst does not require this, but maybe it's assumed like in other test suites (or in perf). | In general, the rules for selftests are | | * Do as much as you can if you're not root; | | * Don't take too long; | | * Don't break the build on any architecture, and | | * Don't cause the top-level "make run_tests" to fail if your feature is | unconfigured. For example LTP says: | LTP test should be as backward compatible as possible. [...] | | Therefore LTP test for more current features should be able to cope with older | systems. Also, (it's said[1]) perf, even though in kernel tree, is supposed to work properly on any (older/newer) version of Linux. Can you clarify this point in kselftest.rst? I think, this would be useful for future kselftests developers, users, and packagers. (Currently, I package for ALT Linux kselftests (and perf) from the latest mainline branch, so people could test even older kernels with the latest kselftests. If there is policy to be backward-compatible kselftests in the future could reach a state where users would run them in all pass mode (without selecting only working tests). This, in turn, would increase [ease of] usability of tests and thus frequency of their run and consequentially quality kernel testing overall. Thanks, [1] https://lkml.org/lkml/2020/7/29/677