From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: 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> In-Reply-To: <20121130185118.302752929@linuxfoundation.org> References: <20121130185118.302752929@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: 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;