From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753823AbaIXI1u (ORCPT ); Wed, 24 Sep 2014 04:27:50 -0400 Received: from mailout1.samsung.com ([203.254.224.24]:48798 "EHLO mailout1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753568AbaIXI1r (ORCPT ); Wed, 24 Sep 2014 04:27:47 -0400 X-AuditID: cbfee61a-f79c06d000004e71-3e-542280815299 From: Lukasz Majewski To: Zhang Rui , Eduardo Valentin Cc: Linux PM list , Lukasz Majewski , Bartlomiej Zolnierkiewicz , linux-kernel@vger.kernel.org, Lukasz Majewski Subject: [PATCH 1/3] thermal: step_wise: fix: Prevent from binary overflow when trend is dropping Date: Wed, 24 Sep 2014 10:27:10 +0200 Message-id: <1411547232-21493-2-git-send-email-l.majewski@samsung.com> X-Mailer: git-send-email 1.7.10.4 In-reply-to: <1411547232-21493-1-git-send-email-l.majewski@samsung.com> References: <1411547232-21493-1-git-send-email-l.majewski@samsung.com> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFprELMWRmVeSWpSXmKPExsVy+t9jAd2mBqUQgyONzBYbZ6xntZh/5Rqr xZtH3BZvHm5mtLi8aw6bxefeI4wWTx72sTmwe+ycdZfdY/Gel0we66a9Zfbo27KK0ePzJrkA 1igum5TUnMyy1CJ9uwSujBVnN7AW7OSoOH59OmMD4x+2LkZODgkBE4lp09YxQdhiEhfurQeK c3EICSxilFjy7RIjhNPFJHFmwyxmkCo2AT2Jz3efAnVwcIgIeEtsWcMBUsMscINRYkr/ZLBJ wgLJEu1zG8FsFgFVib+HOxlB6nkF3CSezayFWKYo0f1sAtgRnALuEjd/P2MHsYWASg7+Osg+ gZF3ASPDKkbR1ILkguKk9FxDveLE3OLSvHS95PzcTYzgkHomtYNxZYPFIUYBDkYlHt4J4koh QqyJZcWVuYcYJTiYlUR4T5QChXhTEiurUovy44tKc1KLDzFKc7AoifMeaLUOFBJITyxJzU5N LUgtgskycXBKNTDOVLWMvmN/ZNcUxv23L0ySscjyfZ8vf3Cnu+K9XX3/fKakKxZP3Drhg9V/ A9P/5WqHUy+z8zPcl801uGnEMEX0wvqf54qa956J1l4/+VCk2Kv2Kz/nTBFweHExJTCDc+vn A2yiH8+GPtk5v+xK7/mL6qunXBWedXj3op27e79cFEt1sb915gS3mRJLcUaioRZzUXEiAKph w5klAgAA Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org It turns out that some boards can have instance->lower greater than 0 and when thermal trend is dropping it results with next_target equal to -1. Since the next_target is defined as unsigned long it is interpreted as 0xFFFFFFFF and larger than instance->upper. As a result the next_target is set to instance->upper which ramps up to maximal cooling device target when the temperature is steadily decreasing. Signed-off-by: Lukasz Majewski --- drivers/thermal/step_wise.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/thermal/step_wise.c b/drivers/thermal/step_wise.c index 3b54c2c..fdd1f52 100644 --- a/drivers/thermal/step_wise.c +++ b/drivers/thermal/step_wise.c @@ -77,7 +77,7 @@ static unsigned long get_target_state(struct thermal_instance *instance, next_target = instance->upper; break; case THERMAL_TREND_DROPPING: - if (cur_state == instance->lower) { + if (cur_state <= instance->lower) { if (!throttle) next_target = THERMAL_NO_TARGET; } else { -- 2.0.0.rc2