From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1769128Ab2K3TWM (ORCPT ); Fri, 30 Nov 2012 14:22:12 -0500 Received: from mail.kernel.org ([198.145.19.201]:58476 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2992739Ab2K3S4e (ORCPT ); Fri, 30 Nov 2012 13:56:34 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , alan@lxorguk.ukuu.org.uk, Guennadi Liakhovetski , "Rafael J. Wysocki" Subject: [ 35/56] PM / QoS: fix wrong error-checking condition Date: Fri, 30 Nov 2012 10:55:27 -0800 Message-Id: <20121130185121.863933752@linuxfoundation.org> X-Mailer: git-send-email 1.8.0.197.g5a90748 In-Reply-To: <20121130185118.302752929@linuxfoundation.org> References: <20121130185118.302752929@linuxfoundation.org> User-Agent: quilt/0.60-2.1.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Guennadi Liakhovetski commit a7227a0faa117d0bc532aea546ae5ac5f89e8ed7 upstream. dev_pm_qos_add_request() can return 0, 1, or a negative error code, therefore the correct error test is "if (error < 0)." Checking just for non-zero return code leads to erroneous setting of the req->dev pointer to NULL, which then leads to a repeated call to dev_pm_qos_add_ancestor_request() in st1232_ts_irq_handler(). This in turn leads to an Oops, when the I2C host adapter is unloaded and reloaded again because of the inconsistent state of its QoS request list. Signed-off-by: Guennadi Liakhovetski Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman --- drivers/base/power/qos.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/base/power/qos.c +++ b/drivers/base/power/qos.c @@ -446,7 +446,7 @@ int dev_pm_qos_add_ancestor_request(stru if (ancestor) error = dev_pm_qos_add_request(ancestor, req, value); - if (error) + if (error < 0) req->dev = NULL; return error;