From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:36981 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728020AbeJNXYb (ORCPT ); Sun, 14 Oct 2018 19:24:31 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Fabio Estevam" , "Mikhail Lappo" , "Dong Aisheng" , "Zhang Rui" , "Philipp Zabel" Date: Sun, 14 Oct 2018 16:25:40 +0100 Message-ID: Subject: [PATCH 3.16 037/366] thermal: imx: Fix race condition in imx_thermal_probe() In-Reply-To: Sender: stable-owner@vger.kernel.org List-ID: 3.16.60-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Mikhail Lappo commit cf1ba1d73a33944d8c1a75370a35434bf146b8a7 upstream. When device boots with T > T_trip_1 and requests interrupt, the race condition takes place. The interrupt comes before THERMAL_DEVICE_ENABLED is set. This leads to an attempt to reading sensor value from irq and disabling the sensor, based on the data->mode field, which expected to be THERMAL_DEVICE_ENABLED, but still stays as THERMAL_DEVICE_DISABLED. Afher this issue sensor is never re-enabled, as the driver state is wrong. Fix this problem by setting the 'data' members prior to requesting the interrupts. Fixes: 37713a1e8e4c ("thermal: imx: implement thermal alarm interrupt handling") Signed-off-by: Mikhail Lappo Signed-off-by: Fabio Estevam Reviewed-by: Philipp Zabel Acked-by: Dong Aisheng Signed-off-by: Zhang Rui Signed-off-by: Ben Hutchings --- drivers/thermal/imx_thermal.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/drivers/thermal/imx_thermal.c +++ b/drivers/thermal/imx_thermal.c @@ -484,6 +484,9 @@ static int imx_thermal_probe(struct plat regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN); regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP); + data->irq_enabled = true; + data->mode = THERMAL_DEVICE_ENABLED; + ret = devm_request_threaded_irq(&pdev->dev, data->irq, imx_thermal_alarm_irq, imx_thermal_alarm_irq_thread, 0, "imx_thermal", data); @@ -495,9 +498,6 @@ static int imx_thermal_probe(struct plat return ret; } - data->irq_enabled = true; - data->mode = THERMAL_DEVICE_ENABLED; - return 0; }