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=-20.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,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 6E197C6377B for ; Wed, 21 Jul 2021 21:08:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5810561404 for ; Wed, 21 Jul 2021 21:08:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230111AbhGUU1z (ORCPT ); Wed, 21 Jul 2021 16:27:55 -0400 Received: from mail.kernel.org ([198.145.29.99]:35894 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229748AbhGUU1i (ORCPT ); Wed, 21 Jul 2021 16:27:38 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id E65EB6141C; Wed, 21 Jul 2021 21:08:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1626901695; bh=EnVzEtFnkzNN4ZcGmW5TGlEOLlti+MulOzrZxzhzTCI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OUvN784FG4vQt/vkDJa13hhH4In8/bUhvid2mt5m8RgGcLqN/vvTcT2/IKhjEOeqt jqyikp/W1HhipUxfFQCmbxdokr62X3rsrnJ8VeZ1TTVJ1iY0pAJA2m+Ffj2swgSpJQ Ne2PdZ4FJGuO+UhEzZol1g4UGM8gr9S6swRpy/+ZzXQntQZ7xPWvZXLXTMyqyodhRt vkBQXYCKNoUpy3/ocnKWv7cto1fvxl6kRA2UQx8rMSCbQvG5yeuG+4wn2BWeRpIwFl 3SImQPxX5JYCGFvvJtTiLkns6nz2BnytZaTyFdPO2aQjIA+2qYYfMSv0zscwxrYjwB bvhQ/KkaPVqyA== Received: by paulmck-ThinkPad-P17-Gen-1.home (Postfix, from userid 1000) id 6C88C5C0C70; Wed, 21 Jul 2021 14:08:14 -0700 (PDT) From: "Paul E. McKenney" To: linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com, kernel-team@fb.com, mingo@kernel.org Cc: elver@google.com, andreyknvl@google.com, glider@google.com, dvyukov@google.com, cai@lca.pw, boqun.feng@gmail.com, Mark Rutland , "Paul E . McKenney" Subject: [PATCH kcsan 6/8] kcsan: Print if strict or non-strict during init Date: Wed, 21 Jul 2021 14:08:10 -0700 Message-Id: <20210721210812.844740-6-paulmck@kernel.org> X-Mailer: git-send-email 2.31.1.189.g2e36527f23 In-Reply-To: <20210721210726.GA828672@paulmck-ThinkPad-P17-Gen-1> References: <20210721210726.GA828672@paulmck-ThinkPad-P17-Gen-1> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Marco Elver Show a brief message if KCSAN is strict or non-strict, and if non-strict also say that CONFIG_KCSAN_STRICT=y can be used to see all data races. This is to hint to users of KCSAN who blindly use the default config that their configuration might miss data races of interest. Signed-off-by: Marco Elver Acked-by: Mark Rutland Signed-off-by: Paul E. McKenney --- kernel/kcsan/core.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/kernel/kcsan/core.c b/kernel/kcsan/core.c index 439edb9dcbb13..76e67d1e02d48 100644 --- a/kernel/kcsan/core.c +++ b/kernel/kcsan/core.c @@ -656,6 +656,15 @@ void __init kcsan_init(void) pr_info("enabled early\n"); WRITE_ONCE(kcsan_enabled, true); } + + if (IS_ENABLED(CONFIG_KCSAN_REPORT_VALUE_CHANGE_ONLY) || + IS_ENABLED(CONFIG_KCSAN_ASSUME_PLAIN_WRITES_ATOMIC) || + IS_ENABLED(CONFIG_KCSAN_PERMISSIVE) || + IS_ENABLED(CONFIG_KCSAN_IGNORE_ATOMICS)) { + pr_warn("non-strict mode configured - use CONFIG_KCSAN_STRICT=y to see all data races\n"); + } else { + pr_info("strict mode configured\n"); + } } /* === Exported interface =================================================== */ -- 2.31.1.189.g2e36527f23