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 63B5D3438B2; Sat, 12 Sep 2026 17:06:41 +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=1789232802; cv=none; b=Nwd4iV+DX04yjwBjuTrvHv1KiTSEYOdFqJFLkperdJL+aPMHJdE8C9sU+62iJO/8Ar1eQRDvjVg65VXVpnROlljYS+9n6ywuBc5o/KlzEni2XQn81ku6niSEp1DTgkcluzbHgQ/mc0TYtw1PZyt/QTeFQ6YxC2ogs5QdXfv8zJk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789232802; c=relaxed/simple; bh=/McRCc9CBQZskUGO+UqegKpMYjH5ENvRfL5Lo95BWKA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=lcXGix/WJWx7funRLpyWXpfkC1dH43nUfM3ChR8dAgvODVGpzSAatIkrI5/u5DztSqREzHqWngPBr7IdTncu8dZmTbzYT1MXrOlqL6Bh3g92qo2gFrDsiVMXDhN5UIJJ2iJZiAWzenNdOW2e9sP5N33e20BTpwx/BZttnqVmjiE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=tWAAGwd7; 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="tWAAGwd7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1D4B81F000FF; Sat, 12 Sep 2026 17:06:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789232801; bh=UuHY5+/13YgyTISU6oaMqpGqAvXT1AZGt80dWYdUTgc=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=tWAAGwd7dIx8NvUNqZfPFaCLv5UGOlpCtIC7YQkShEvP2o5XrvrFwiz9O/L7HexYW yJXiPMKLh939iEcX9sjeYAvz29Zv7M0WPVACnRtyh9jSzBreZ8wM7mY2vOmLTGCjko doRsIxL4HS3cz/jvV1bmcaxRFnFo2zNji9fTtELY= 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 5.15 085/935] auxdisplay: charlcd: cancel backlight work on registration failure Date: Sat, 12 Sep 2026 08:51:55 +0200 Message-ID: <20260912065528.776637078@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065526.833703348@linuxfoundation.org> References: <20260912065526.833703348@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 5.15-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; }