From mboxrd@z Thu Jan 1 00:00:00 1970 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 2C0F33CAA41; Wed, 30 Sep 2026 19:12:09 +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=1790795530; cv=none; b=SsrrxqcFsBB52/BicfuPnQ3ckZk3GF/IqZ1ERhNkWttFtBqbSEbi75AoWokwmovMAEeKRbMAFzDs4jE7fFKUQyRnpeCHJiGqU/Ql6+q0mu4dz2itV/Atxzvxh9VM4EAvY6up8rBFajcPupmcNXfjBZBCqNgTtse0UB98EGawZX8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790795530; c=relaxed/simple; bh=cNEKWABNOkFFxEaQ3nHdTu7iQIymznykU5+Nk0UAIOU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=BeLmlh+EicZa5TXGFZSTvfZszJf0jmQMSwFmJhRvsJYSAO003KOoY4QbbGLXgv+7K7iw7ZY+f2v+hG4i+mmpE89bG+mGS/0Sw+WId88w/wD6omwnWgCiSxIojErmJBSFFvYNQdw45ejKt4kChWdEHonS3Roq3AIoSW4BVl6PXgE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=RpNt21JA; 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="RpNt21JA" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8444B1F000FF; Wed, 30 Sep 2026 19:12:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790795529; bh=fkShyOWFmAfBu357jHgfxKvmD8Hmkhw7T0YXziXWet0=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=RpNt21JAfDs6Q16f/fQDZwpg+i9AJeTQsteegyTkO5BwbNIAr9E4IkKQGekY0tIJU fmlOBShKmwf3egrH2UtMgeclZbbozAhxcLm3djbP5p4WvlKvRvb0tgaqifltPf1zal H+OgO67wvX9SHxDfrLAOPZ/MTZxPjM9aUpbM/Jes= 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 6.6 0566/1193] hwmon: (gpio-fan) take fan_data->lock in gpio_fan_shutdown() Date: Wed, 30 Sep 2026 17:20:50 +0200 Message-ID: <20260930152446.816916218@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260930152434.301151190@linuxfoundation.org> References: <20260930152434.301151190@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 6.6-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 b779240328d59..cee3fa146d69a 100644 --- a/drivers/hwmon/gpio-fan.c +++ b/drivers/hwmon/gpio-fan.c @@ -561,8 +561,11 @@ 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_suspend(struct device *dev) -- 2.53.0