Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753437AbcDRLCL (ORCPT ); Mon, 18 Apr 2016 07:02:11 -0400 Received: from mail.kernel.org ([198.145.29.136]:35354 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752596AbcDRKu4 (ORCPT ); Mon, 18 Apr 2016 06:50:56 -0400 From: lizf@kernel.org To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, John Stultz , Prarit Bhargava , Richard Cochran , Ingo Molnar , Thomas Gleixner , Zefan Li Subject: [PATCH 3.4 70/92] clocksource: Fix abs() usage w/ 64bit values Date: Mon, 18 Apr 2016 18:46:15 +0800 Message-Id: <1460976397-5688-70-git-send-email-lizf@kernel.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1460976338-5631-1-git-send-email-lizf@kernel.org> References: <1460976338-5631-1-git-send-email-lizf@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1445 Lines: 42 From: John Stultz 3.4.112-rc1 review patch. If anyone has any objections, please let me know. ------------------ commit 67dfae0cd72fec5cd158b6e5fb1647b7dbe0834c upstream. This patch fixes one cases where abs() was being used with 64-bit nanosecond values, where the result may be capped at 32-bits. This potentially could cause watchdog false negatives on 32-bit systems, so this patch addresses the issue by using abs64(). Signed-off-by: John Stultz Cc: Prarit Bhargava Cc: Richard Cochran Cc: Ingo Molnar Link: http://lkml.kernel.org/r/1442279124-7309-2-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner [lizf: Backported to 3.4: adjust context] Signed-off-by: Zefan Li --- kernel/time/clocksource.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index c958338..b3f5407 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -291,7 +291,7 @@ static void clocksource_watchdog(unsigned long data) continue; /* Check the deviation from the watchdog clocksource. */ - if ((abs(cs_nsec - wd_nsec) > WATCHDOG_THRESHOLD)) { + if ((abs64(cs_nsec - wd_nsec) > WATCHDOG_THRESHOLD)) { clocksource_unstable(cs, cs_nsec - wd_nsec); continue; } -- 1.9.1