From mboxrd@z Thu Jan 1 00:00:00 1970 From: Frank Li Subject: [PATCH 1/1] net: fec: fix crash at mx53 qsb board Date: Thu, 21 Feb 2013 09:07:28 +0800 Message-ID: <1361408848-14118-1-git-send-email-Frank.Li@freescale.com> Mime-Version: 1.0 Content-Type: text/plain Cc: , , , , Frank Li To: , , , Return-path: Received: from db3ehsobe004.messaging.microsoft.com ([213.199.154.142]:20663 "EHLO db3outboundpool.messaging.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752390Ab3BUCIz (ORCPT ); Wed, 20 Feb 2013 21:08:55 -0500 Sender: netdev-owner@vger.kernel.org List-ID: Unable to handle kernel NULL pointer dereference at virtual address 00000002 pgd = 80004000 [00000002] *pgd=00000000 Internal error: Oops: 5 [#1] SMP ARM Modules linked in: CPU: 0 Not tainted (3.8.0-rc7-next-20130215+ #346) PC is at fec_enet_interrupt+0xd0/0x348 LR is at fec_enet_interrupt+0xb8/0x348 pc : [<80372b7c>] lr : [<80372b64>] psr: 60000193 sp : df855c20 ip : df855c20 fp : df855c74 r10: 00000516 r9 : 1c000000 r8 : 00000000 r7 : 00000000 r6 : 00000000 r5 : 00000000 r4 : df9b7800 r3 : df9b7df4 r2 : 00000000 r1 : 00000000 r0 : df9b7d34 It is possible that issue a irq between request_irq and fec_enet_init. Irq handle will be called but driver data structure is not ready yet. Signed-off-by: Frank Li --- drivers/net/ethernet/freescale/fec.c | 8 +++++++- 1 files changed, 7 insertions(+), 1 deletions(-) diff --git a/drivers/net/ethernet/freescale/fec.c b/drivers/net/ethernet/freescale/fec.c index 7c6e890..a860486 100644 --- a/drivers/net/ethernet/freescale/fec.c +++ b/drivers/net/ethernet/freescale/fec.c @@ -1676,7 +1676,6 @@ static int fec_enet_init(struct net_device *ndev) ndev->netdev_ops = &fec_netdev_ops; ndev->ethtool_ops = &fec_enet_ethtool_ops; - writel(FEC_RX_DISABLED_IMASK, fep->hwp + FEC_IMASK); netif_napi_add(ndev, &fep->napi, fec_enet_rx_napi, FEC_NAPI_WEIGHT); /* Init enet descriptors */ @@ -1786,6 +1785,13 @@ fec_probe(struct platform_device *pdev) fep->pdev = pdev; fep->dev_id = dev_id++; + /* + * disable and clean all irq to avoid unexpected irq happen + * between init driver data structure and request_irq + */ + writel(0, fep->hwp + FEC_IMASK); + writel(0xFFFFFFFF, fep->hwp + FEC_IEVENT); + fep->bufdesc_ex = 0; if (!fep->hwp) { -- 1.7.1