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=-13.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 0AE48C433E8 for ; Thu, 23 Jul 2020 20:11:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E0AE720792 for ; Thu, 23 Jul 2020 20:11:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727041AbgGWULC (ORCPT ); Thu, 23 Jul 2020 16:11:02 -0400 Received: from mail.fireflyinternet.com ([77.68.26.236]:52420 "EHLO fireflyinternet.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726033AbgGWULB (ORCPT ); Thu, 23 Jul 2020 16:11:01 -0400 X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=78.156.65.138; Received: from build.alporthouse.com (unverified [78.156.65.138]) by fireflyinternet.com (Firefly Internet (M1)) with ESMTP id 21911950-1500050 for multiple; Thu, 23 Jul 2020 21:10:44 +0100 From: Chris Wilson To: linux-kernel@vger.kernel.org Cc: Chris Wilson , Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot Subject: [PATCH] sched: Warn if garbage is passed to default_wake_function() Date: Thu, 23 Jul 2020 21:10:42 +0100 Message-Id: <20200723201042.18861-1-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Since the default_wake_function() passes its flags onto try_to_wake_up(), warn if those flags collide with internal values. Given that the supplied flags are garbage, no repair can be done but at least alert the user to the damage they are causing. In the belief that these errors should be picked up during testing, the warning is only compiled in under CONFIG_SCHED_DEBUG. Signed-off-by: Chris Wilson Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Juri Lelli Cc: Vincent Guittot --- kernel/sched/core.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 7b918059332b..4be209266d8a 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -4481,6 +4481,7 @@ asmlinkage __visible void __sched preempt_schedule_irq(void) int default_wake_function(wait_queue_entry_t *curr, unsigned mode, int wake_flags, void *key) { + WARN_ON_ONCE(IS_ENABLED(CONFIG_SCHED_DEBUG) && wake_flags & ~WF_SYNC); return try_to_wake_up(curr->private, mode, wake_flags); } EXPORT_SYMBOL(default_wake_function); -- 2.20.1