Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 00BA74ED1B9; Thu, 17 Sep 2026 17:29:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789666151; cv=none; b=ouztz61sjP2GQlKTBQjHw2VF8V6Ncpgk/71A0HGBB7t6+VTnv95xU1cDbyUctVWN/VxZumLTdBLT2RpAmmuHq5O8pkhEOum7DtskfoqI40rZLyCSUCBa0Gk3auosfyW0PySHSlCvINeM1RWTJOm5O9TLT2DLyxcXa3xDFjlTpS8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789666151; c=relaxed/simple; bh=pMS4L/jhdSSjihfZnwLbUFlN/tkdAM8g7qr67j6XhCw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=BuqKjECPs+cxIvvNxNU/MRPM3mXuoyRWioK0zCby+F9dTdTiCoDtXJdhblzts2/enxEUgyWxchUFB7W66jeGeF9kh1n/Lug7H5hoUbpDn5YTKcSBs+9PHev8labeYFkegjs+hodqWBLCO9X+9V1amd7nQVvMuQtTEJ1P9LoW8+A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=POjDL6lw; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="POjDL6lw" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 59FBD1F000FF; Thu, 17 Sep 2026 17:29:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789666149; bh=gsFTTmtEx6A4zEqZIcLcXABV6KLF5K6MKADU9d9URRw=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=POjDL6lwAq2uSkO3avh69+TblvLE9lYbdvjUB+7t6sI7rKUw39I6S21UkUaU5BzSH loQ10+N40qJ1OQZBe/jp+0eYxNpxMCPMA6OPQUxCXzM2UltxDMSa8tKvCRq/1BvtcW SEDOJBPjvA+buOxauS6jGNj4nLHqFjpmeIEWpvyU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Sashiko AI review , Cong Nguyen , Guenter Roeck , Sasha Levin Subject: [PATCH 6.18 0902/1250] hwmon: (gpio-fan) take fan_data->lock in gpio_fan_shutdown() Date: Thu, 17 Sep 2026 16:11:37 +0100 Message-ID: <20260917151616.439859212@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260917151551.901433442@linuxfoundation.org> References: <20260917151551.901433442@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Cong Nguyen [ Upstream commit bb2424c3502cc72292eedade46960c331d5f28fb ] set_fan_speed() writes the control GPIOs one bit at a time. Every other caller locks around it; gpio_fan_shutdown() doesn't. If it races a locked caller, the GPIO writes can interleave and leave the fan at a speed neither caller asked for. Fixes: b95579cd8795 ("hwmon: (gpio-fan) Add a shutdown handler to poweroff the fans") Reported-by: Sashiko AI review Link: https://lore.kernel.org/r/20260830152150.27F5F1F000E9@smtp.kernel.org Assisted-by: Claude:claude-opus-4 Signed-off-by: Cong Nguyen Link: https://patch.msgid.link/20260901155404.1532092-1-congnt264@gmail.com Signed-off-by: Guenter Roeck Signed-off-by: Sasha Levin --- drivers/hwmon/gpio-fan.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/hwmon/gpio-fan.c b/drivers/hwmon/gpio-fan.c index a8892ced1e549..0da51041959c5 100644 --- a/drivers/hwmon/gpio-fan.c +++ b/drivers/hwmon/gpio-fan.c @@ -604,8 +604,11 @@ static void gpio_fan_shutdown(struct platform_device *pdev) { struct gpio_fan_data *fan_data = platform_get_drvdata(pdev); - if (fan_data->gpios) + if (fan_data->gpios) { + mutex_lock(&fan_data->lock); set_fan_speed(fan_data, 0); + mutex_unlock(&fan_data->lock); + } } static int gpio_fan_runtime_suspend(struct device *dev) -- 2.53.0