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=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 2F789C5519F for ; Tue, 17 Nov 2020 15:17:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C15A224198 for ; Tue, 17 Nov 2020 15:17:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="Mwt9xzt/" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731173AbgKQPQz (ORCPT ); Tue, 17 Nov 2020 10:16:55 -0500 Received: from mail.kernel.org ([198.145.29.99]:34320 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729184AbgKQPQy (ORCPT ); Tue, 17 Nov 2020 10:16:54 -0500 Received: from localhost.localdomain (unknown [176.167.180.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 74BCC24198; Tue, 17 Nov 2020 15:16:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1605626214; bh=XOYPcNdLuOm9X4SGxF8og/EAggpsSwLDja/L9sZfhxM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Mwt9xzt/QnBvf6Yg7babjB44SIoMq1D6MhUY0cGB5UpgsNirKxov5QcleII6OGeDY c8+BYRRGU29b07rmjoPW2zMbJgSBt51LBQC7IfClg2LISWc0cOElX/ky5xGBXWk2/4 LMoFDw8K/yIkrIWwgyQ9K4lJNkPWhKqgz9LzGenE= From: Frederic Weisbecker To: Peter Zijlstra Cc: LKML , Frederic Weisbecker , "Paul E . McKenney" , Thomas Gleixner , Phil Auld , Marcelo Tosatti Subject: [PATCH 3/5] sched: Detect call to schedule from critical entry code Date: Tue, 17 Nov 2020 16:16:35 +0100 Message-Id: <20201117151637.259084-4-frederic@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20201117151637.259084-1-frederic@kernel.org> References: <20201117151637.259084-1-frederic@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Detect calls to schedule() between user_enter() and user_exit(). Those are symptoms of early entry code that either forgot to protect a call to schedule() inside exception_enter()/exception_exit() or, in the case of HAVE_CONTEXT_TRACKING_OFFSTACK, enabled interrupts or preemption in a wrong spot. Signed-off-by: Frederic Weisbecker Cc: Marcelo Tosatti Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Phil Auld Cc: Thomas Gleixner --- kernel/sched/core.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index d2003a7d5ab5..c23d7cb5aee3 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -4291,6 +4291,7 @@ static inline void schedule_debug(struct task_struct *prev, bool preempt) preempt_count_set(PREEMPT_DISABLED); } rcu_sleep_check(); + SCHED_WARN_ON(ct_state() == CONTEXT_USER); profile_hit(SCHED_PROFILING, __builtin_return_address(0)); -- 2.25.1