From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E6A43C32771 for ; Wed, 22 Jan 2020 22:25:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BB9D12465A for ; Wed, 22 Jan 2020 22:25:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729235AbgAVWZA (ORCPT ); Wed, 22 Jan 2020 17:25:00 -0500 Received: from kvm5.telegraphics.com.au ([98.124.60.144]:47776 "EHLO kvm5.telegraphics.com.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726061AbgAVWYC (ORCPT ); Wed, 22 Jan 2020 17:24:02 -0500 Received: by kvm5.telegraphics.com.au (Postfix, from userid 502) id 4DA5B299A6; Wed, 22 Jan 2020 17:23:59 -0500 (EST) To: "David S. Miller" Cc: Thomas Bogendoerfer , Chris Zankel , Laurent Vivier , Geert Uytterhoeven , Eric Dumazet , Stephen Hemminger , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Message-Id: <7927d3de3f46e660c0112aefb1a63bf1584c187d.1579730846.git.fthain@telegraphics.com.au> In-Reply-To: References: From: Finn Thain Subject: [PATCH net v3 02/12] net/sonic: Clear interrupt flags immediately Date: Thu, 23 Jan 2020 09:07:26 +1100 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The chip can change a packet's descriptor status flags at any time. However, an active interrupt flag gets cleared rather late. This allows a race condition that could theoretically lose an interrupt. Fix this by clearing asserted interrupt flags immediately. Fixes: efcce839360f ("[PATCH] macsonic/jazzsonic network drivers update") Tested-by: Stan Johnson Signed-off-by: Finn Thain --- drivers/net/ethernet/natsemi/sonic.c | 28 ++++++---------------------- 1 file changed, 6 insertions(+), 22 deletions(-) diff --git a/drivers/net/ethernet/natsemi/sonic.c b/drivers/net/ethernet/natsemi/sonic.c index 8a7cff516281..1109070a5154 100644 --- a/drivers/net/ethernet/natsemi/sonic.c +++ b/drivers/net/ethernet/natsemi/sonic.c @@ -304,10 +304,11 @@ static irqreturn_t sonic_interrupt(int irq, void *dev_id) } do { + SONIC_WRITE(SONIC_ISR, status); /* clear the interrupt(s) */ + if (status & SONIC_INT_PKTRX) { netif_dbg(lp, intr, dev, "%s: packet rx\n", __func__); sonic_rx(dev); /* got packet(s) */ - SONIC_WRITE(SONIC_ISR, SONIC_INT_PKTRX); /* clear the interrupt */ } if (status & SONIC_INT_TXDN) { @@ -362,7 +363,6 @@ static irqreturn_t sonic_interrupt(int irq, void *dev_id) if (freed_some || lp->tx_skb[entry] == NULL) netif_wake_queue(dev); /* The ring is no longer full */ lp->cur_tx = entry; - SONIC_WRITE(SONIC_ISR, SONIC_INT_TXDN); /* clear the interrupt */ } /* @@ -372,42 +372,31 @@ static irqreturn_t sonic_interrupt(int irq, void *dev_id) netif_dbg(lp, rx_err, dev, "%s: rx fifo overrun\n", __func__); lp->stats.rx_fifo_errors++; - SONIC_WRITE(SONIC_ISR, SONIC_INT_RFO); /* clear the interrupt */ } if (status & SONIC_INT_RDE) { netif_dbg(lp, rx_err, dev, "%s: rx descriptors exhausted\n", __func__); lp->stats.rx_dropped++; - SONIC_WRITE(SONIC_ISR, SONIC_INT_RDE); /* clear the interrupt */ } if (status & SONIC_INT_RBAE) { netif_dbg(lp, rx_err, dev, "%s: rx buffer area exceeded\n", __func__); lp->stats.rx_dropped++; - SONIC_WRITE(SONIC_ISR, SONIC_INT_RBAE); /* clear the interrupt */ } /* counter overruns; all counters are 16bit wide */ - if (status & SONIC_INT_FAE) { + if (status & SONIC_INT_FAE) lp->stats.rx_frame_errors += 65536; - SONIC_WRITE(SONIC_ISR, SONIC_INT_FAE); /* clear the interrupt */ - } - if (status & SONIC_INT_CRC) { + if (status & SONIC_INT_CRC) lp->stats.rx_crc_errors += 65536; - SONIC_WRITE(SONIC_ISR, SONIC_INT_CRC); /* clear the interrupt */ - } - if (status & SONIC_INT_MP) { + if (status & SONIC_INT_MP) lp->stats.rx_missed_errors += 65536; - SONIC_WRITE(SONIC_ISR, SONIC_INT_MP); /* clear the interrupt */ - } /* transmit error */ - if (status & SONIC_INT_TXER) { + if (status & SONIC_INT_TXER) if (SONIC_READ(SONIC_TCR) & SONIC_TCR_FU) netif_dbg(lp, tx_err, dev, "%s: tx fifo underrun\n", __func__); - SONIC_WRITE(SONIC_ISR, SONIC_INT_TXER); /* clear the interrupt */ - } /* bus retry */ if (status & SONIC_INT_BR) { @@ -416,13 +405,8 @@ static irqreturn_t sonic_interrupt(int irq, void *dev_id) /* ... to help debug DMA problems causing endless interrupts. */ /* Bounce the eth interface to turn on the interrupt again. */ SONIC_WRITE(SONIC_IMR, 0); - SONIC_WRITE(SONIC_ISR, SONIC_INT_BR); /* clear the interrupt */ } - /* load CAM done */ - if (status & SONIC_INT_LCD) - SONIC_WRITE(SONIC_ISR, SONIC_INT_LCD); /* clear the interrupt */ - status = SONIC_READ(SONIC_ISR) & SONIC_IMR_DEFAULT; } while (status); -- 2.24.1