From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755682AbdJMHCM (ORCPT ); Fri, 13 Oct 2017 03:02:12 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:45627 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751504AbdJMHCL (ORCPT ); Fri, 13 Oct 2017 03:02:11 -0400 Date: Fri, 13 Oct 2017 10:01:22 +0300 From: Dan Carpenter To: Ingo Molnar , luca abeni Cc: Peter Zijlstra , linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: [PATCH] sched/deadline: Don't use dubious signed bitfields Message-ID: <20171013070121.dzcncojuj2f4utij@mwanda> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Mailer: git-send-email haha only kidding User-Agent: NeoMutt/20170609 (1.8.3) X-Source-IP: userv0021.oracle.com [156.151.31.71] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org It doesn't cause a run-time bug, but these bitfields should be unsigned. When it's signed ->dl_throttled is set to either 0 or -1, instead of 0 and 1 as expected. The sched.h file is included into tons of places so Sparse generates a flood of warnings like this: ./include/linux/sched.h:477:54: error: dubious one-bit signed bitfield Signed-off-by: Dan Carpenter diff --git a/include/linux/sched.h b/include/linux/sched.h index 0f897dfc195e..105eaff8a5e7 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -474,10 +474,10 @@ struct sched_dl_entity { * conditions between the inactive timer handler and the wakeup * code. */ - int dl_throttled : 1; - int dl_boosted : 1; - int dl_yielded : 1; - int dl_non_contending : 1; + unsigned int dl_throttled : 1; + unsigned int dl_boosted : 1; + unsigned int dl_yielded : 1; + unsigned int dl_non_contending : 1; /* * Bandwidth enforcement timer. Each -deadline task has its