From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 A7BDA21ABDB; Tue, 29 Apr 2025 17:20:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745947248; cv=none; b=Gjxfpn6hu0/qLeprdBIv3FkQ+fyCFxuCtoOQellDFgzLP87t9QjaqDYeF35qCF2gwYjAoJ8neMNpx9n9aWSGMUwcdliXOW68Pcs9i3cMmwEDvHmoB7bsK1nf+UjUV1N61cRUeyla2sH8OJsKXYdQFp9madcOZRR0WSks+f5xAGE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745947248; c=relaxed/simple; bh=f3u+l5icYdG7KnNdskH/WSP7B79pq0jvsUqIwUhAOAk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=rdimplg4+zDUMiBYagJZtOh02Ie0tLKjY4QTt/pv6a0Q+Mgk7HeBR4pR3pZfIdlxpuRX4IJL/cIPuVAvkyXa3yJj6k/sT5XthjU4gyYeVg6XIMzL37/PGFN+U4bN5NNB7Hyiavg6VhbK8Gc0m/VwBDPaqsdmM3/r5wf/UWd4A8Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=JOAwwFT+; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="JOAwwFT+" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0B151C4CEE3; Tue, 29 Apr 2025 17:20:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1745947248; bh=f3u+l5icYdG7KnNdskH/WSP7B79pq0jvsUqIwUhAOAk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JOAwwFT+e7hYJOrFG89q5EypSJ92x+3f6k5OFNf9v+CbP4n2oAMWSqJGpEyqOoOrE CCABS+vevQ7OO9oZbVNsDdQmcA4S3IoLozpKpUGVWoL9UODndjXtKi4jBgYSOCY/Fc tXibmc0d7b6Zdo1hjc7SjgA9PCAE76AuhG/672rw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Herve Codina , Lee Jones , Sasha Levin Subject: [PATCH 5.10 219/286] backlight: led_bl: Hold led_access lock when calling led_sysfs_disable() Date: Tue, 29 Apr 2025 18:42:03 +0200 Message-ID: <20250429161116.955469616@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250429161107.848008295@linuxfoundation.org> References: <20250429161107.848008295@linuxfoundation.org> User-Agent: quilt/0.68 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 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Herve Codina [ Upstream commit 276822a00db3c1061382b41e72cafc09d6a0ec30 ] Lockdep detects the following issue on led-backlight removal: [ 142.315935] ------------[ cut here ]------------ [ 142.315954] WARNING: CPU: 2 PID: 292 at drivers/leds/led-core.c:455 led_sysfs_enable+0x54/0x80 ... [ 142.500725] Call trace: [ 142.503176] led_sysfs_enable+0x54/0x80 (P) [ 142.507370] led_bl_remove+0x80/0xa8 [led_bl] [ 142.511742] platform_remove+0x30/0x58 [ 142.515501] device_remove+0x54/0x90 ... Indeed, led_sysfs_enable() has to be called with the led_access lock held. Hold the lock when calling led_sysfs_disable(). Fixes: ae232e45acf9 ("backlight: add led-backlight driver") Cc: stable@vger.kernel.org Signed-off-by: Herve Codina Link: https://lore.kernel.org/r/20250122091914.309533-1-herve.codina@bootlin.com Signed-off-by: Lee Jones Signed-off-by: Sasha Levin --- drivers/video/backlight/led_bl.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) --- a/drivers/video/backlight/led_bl.c +++ b/drivers/video/backlight/led_bl.c @@ -226,8 +226,11 @@ static int led_bl_remove(struct platform backlight_device_unregister(bl); led_bl_power_off(priv); - for (i = 0; i < priv->nb_leds; i++) + for (i = 0; i < priv->nb_leds; i++) { + mutex_lock(&priv->leds[i]->led_access); led_sysfs_enable(priv->leds[i]); + mutex_unlock(&priv->leds[i]->led_access); + } return 0; }