From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755828Ab3AMRqZ (ORCPT ); Sun, 13 Jan 2013 12:46:25 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:35180 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755706Ab3AMRpu (ORCPT ); Sun, 13 Jan 2013 12:45:50 -0500 Message-Id: <20130113174300.852671306@decadent.org.uk> User-Agent: quilt/0.60-1 Date: Sun, 13 Jan 2013 17:43:19 +0000 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, =?UTF-8?q?Lothar=20Wa=C3=9Fmann?= , Juergen Beisert , Lauri Hintsala , Shawn Guo Subject: [ 24/49] video: mxsfb: fix crash when unblanking the display In-Reply-To: <20130113174255.736888844@decadent.org.uk> X-SA-Exim-Connect-IP: 2001:470:1f08:1539:21c:bfff:fe03:f805 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Lothar Waßmann commit 6c1ecba8d84841277d68140ef485335d5be28485 upstream. The VDCTRL4 register does not provide the MXS SET/CLR/TOGGLE feature. The write in mxsfb_disable_controller() sets the data_cnt for the LCD DMA to 0 which obviously means the max. count for the LCD DMA and leads to overwriting arbitrary memory when the display is unblanked. Signed-off-by: Lothar Waßmann Acked-by: Juergen Beisert Tested-by: Lauri Hintsala Signed-off-by: Shawn Guo Signed-off-by: Ben Hutchings --- drivers/video/mxsfb.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/video/mxsfb.c +++ b/drivers/video/mxsfb.c @@ -366,7 +366,8 @@ static void mxsfb_disable_controller(str loop--; } - writel(VDCTRL4_SYNC_SIGNALS_ON, host->base + LCDC_VDCTRL4 + REG_CLR); + reg = readl(host->base + LCDC_VDCTRL4); + writel(reg & ~VDCTRL4_SYNC_SIGNALS_ON, host->base + LCDC_VDCTRL4); clk_disable(host->clk);