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 1C9A3370AFD; Sat, 12 Sep 2026 13:36:12 +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=1789220174; cv=none; b=b4P11rbN5rzz8KLZc8tvKkMOGNtATYVs6gpWL1DGxSYYRFYhKtBX7PRxydM/sBug58G4G70B6efbABhdIGOY9qZReOrY77SbopZcl+pF0xnbTBeOuJhqH6TkqQpJiVo9CkMlobGwZWP76yedD1Hvl7BoeGt/85CgHx5xPRPU5PU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789220174; c=relaxed/simple; bh=EgUFyaoMnEbjrcFesz9PIhzICCW4rC2XePmagtatSAM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=LjFedDLW0I0VjYXqSpkzD519ZHwH5p78RMABMS3pej7WeAuOtqHDTY7VVODJWe6MoF4nLeY8qYK2FkcJsx/CJm4h9voO5TEZfJ41k5xVnQMfqOcCIL08/fFaLP8KNvWoJW555weJzmzh+piVAaBMJpAEQNDZgzJsdzRlMdqGFDk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=RaQATsaw; 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="RaQATsaw" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A34AF1F000FF; Sat, 12 Sep 2026 13:36:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789220172; bh=MluqausvSH9kp9ZMW0OCq9oswk70RhgnBRAe4NbWAJY=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=RaQATsawAFf5xmeVo6QRuo4uQ0FcaGgKSRHRpxkIpJHK1e553wl1j0H/CviQ+kY1Y IAz3np4yLPggvqI0HMyzbD1u/UA17X/Jk+LcyGaTYHUty3aB1xKgbJGr3F8mn9C4+H WRaewjObycOJaBHjb51lOBk/CznaMc28Nyyve8jY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Geert Uytterhoeven , Hongyan Xu , Andy Shevchenko Subject: [PATCH 6.6 0116/1424] auxdisplay: charlcd: cancel backlight work on registration failure Date: Sat, 12 Sep 2026 08:42:28 +0200 Message-ID: <20260912065609.901834666@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065607.279695368@linuxfoundation.org> References: <20260912065607.279695368@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: Hongyan Xu commit e3e3bf40916c1e810df03958cfa7ba6883cdce79 upstream. With CONFIG_CHARLCD_BL_FLASH, charlcd_init() schedules bl_work before charlcd_register() calls misc_register(). If registration fails, the caller frees the charlcd object while delayed work still contains its address. Add charlcd_deinit() to cancel the delayed work and turn the backlight off. Use it for both registration rollback and normal unregistration. Fixes: 39f8ea46724e ("auxdisplay: charlcd: Extract character LCD core from misc/panel") Cc: stable@vger.kernel.org Reviewed-by: Geert Uytterhoeven Signed-off-by: Hongyan Xu Signed-off-by: Andy Shevchenko Signed-off-by: Greg Kroah-Hartman --- drivers/auxdisplay/charlcd.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) --- a/drivers/auxdisplay/charlcd.c +++ b/drivers/auxdisplay/charlcd.c @@ -594,6 +594,16 @@ static int charlcd_init(struct charlcd * return 0; } +static void charlcd_deinit(struct charlcd *lcd) +{ + struct charlcd_priv *priv = charlcd_to_priv(lcd); + + if (lcd->ops->backlight) { + cancel_delayed_work_sync(&priv->bl_work); + lcd->ops->backlight(lcd, CHARLCD_OFF); + } +} + struct charlcd *charlcd_alloc(unsigned int drvdata_size) { struct charlcd_priv *priv; @@ -653,8 +663,10 @@ int charlcd_register(struct charlcd *lcd return ret; ret = misc_register(&charlcd_dev); - if (ret) + if (ret) { + charlcd_deinit(lcd); return ret; + } the_charlcd = lcd; register_reboot_notifier(&panel_notifier); @@ -664,16 +676,11 @@ EXPORT_SYMBOL_GPL(charlcd_register); int charlcd_unregister(struct charlcd *lcd) { - struct charlcd_priv *priv = charlcd_to_priv(lcd); - unregister_reboot_notifier(&panel_notifier); charlcd_puts(lcd, "\x0cLCD driver unloaded.\x1b[Lc\x1b[Lb\x1b[L-"); misc_deregister(&charlcd_dev); the_charlcd = NULL; - if (lcd->ops->backlight) { - cancel_delayed_work_sync(&priv->bl_work); - priv->lcd.ops->backlight(&priv->lcd, CHARLCD_OFF); - } + charlcd_deinit(lcd); return 0; }