From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754222AbaC3Xrn (ORCPT ); Sun, 30 Mar 2014 19:47:43 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:37332 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754803AbaC3Xny (ORCPT ); Sun, 30 Mar 2014 19:43:54 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Marc Kleine-Budde" Date: Mon, 31 Mar 2014 00:23:35 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 155/200] can: flexcan: fix shutdown: first disable chip, then all interrupts In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.249 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 3.2.56-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Marc Kleine-Budde commit 5be93bdda64e85450598c6e97f79fb8f6acf30e0 upstream. When shutting down the CAN interface (ifconfig canX down) during high CAN bus loads, the CAN core might hang and freeze the whole CPU. This patch fixes the shutdown sequence by first disabling the CAN core then disabling all interrupts. Signed-off-by: Marc Kleine-Budde [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- drivers/net/can/flexcan.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) --- a/drivers/net/can/flexcan.c +++ b/drivers/net/can/flexcan.c @@ -777,14 +777,16 @@ static void flexcan_chip_stop(struct net struct flexcan_regs __iomem *regs = priv->base; u32 reg; - /* Disable all interrupts */ - flexcan_write(0, ®s->imask1); - /* Disable + halt module */ reg = flexcan_read(®s->mcr); reg |= FLEXCAN_MCR_MDIS | FLEXCAN_MCR_HALT; flexcan_write(reg, ®s->mcr); + /* Disable all interrupts */ + flexcan_write(0, ®s->imask1); + flexcan_write(priv->reg_ctrl_default & ~FLEXCAN_CTRL_ERR_ALL, + ®s->ctrl); + flexcan_transceiver_switch(priv, 0); priv->can.state = CAN_STATE_STOPPED;