From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:50920 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730649AbeKLFs2 (ORCPT ); Mon, 12 Nov 2018 00:48:28 -0500 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" , "Michal Simek" , "Anssi Hannula" Date: Sun, 11 Nov 2018 19:49:05 +0000 Message-ID: Subject: [PATCH 3.16 286/366] can: xilinx_can: fix incorrect clear of non-processed interrupts In-Reply-To: Sender: stable-owner@vger.kernel.org List-ID: 3.16.61-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Anssi Hannula commit 2f4f0f338cf453bfcdbcf089e177c16f35f023c8 upstream. xcan_interrupt() clears ERROR|RXOFLV|BSOFF|ARBLST interrupts if any of them is asserted. This does not take into account that some of them could have been asserted between interrupt status read and interrupt clear, therefore clearing them without handling them. Fix the code to only clear those interrupts that it knows are asserted and therefore going to be processed in xcan_err_interrupt(). Fixes: b1201e44f50b ("can: xilinx CAN controller support") Signed-off-by: Anssi Hannula Cc: Michal Simek Signed-off-by: Marc Kleine-Budde Signed-off-by: Ben Hutchings --- drivers/net/can/xilinx_can.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) --- a/drivers/net/can/xilinx_can.c +++ b/drivers/net/can/xilinx_can.c @@ -939,6 +939,7 @@ static irqreturn_t xcan_interrupt(int ir struct net_device *ndev = (struct net_device *)dev_id; struct xcan_priv *priv = netdev_priv(ndev); u32 isr, ier; + u32 isr_errors; /* Get the interrupt status from Xilinx CAN */ isr = priv->read_reg(priv, XCAN_ISR_OFFSET); @@ -957,11 +958,10 @@ static irqreturn_t xcan_interrupt(int ir xcan_tx_interrupt(ndev, isr); /* Check for the type of error interrupt and Processing it */ - if (isr & (XCAN_IXR_ERROR_MASK | XCAN_IXR_RXOFLW_MASK | - XCAN_IXR_BSOFF_MASK | XCAN_IXR_ARBLST_MASK)) { - priv->write_reg(priv, XCAN_ICR_OFFSET, (XCAN_IXR_ERROR_MASK | - XCAN_IXR_RXOFLW_MASK | XCAN_IXR_BSOFF_MASK | - XCAN_IXR_ARBLST_MASK)); + isr_errors = isr & (XCAN_IXR_ERROR_MASK | XCAN_IXR_RXOFLW_MASK | + XCAN_IXR_BSOFF_MASK | XCAN_IXR_ARBLST_MASK); + if (isr_errors) { + priv->write_reg(priv, XCAN_ICR_OFFSET, isr_errors); xcan_err_interrupt(ndev, isr); }