Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759835AbZDGQgj (ORCPT ); Tue, 7 Apr 2009 12:36:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758946AbZDGQgL (ORCPT ); Tue, 7 Apr 2009 12:36:11 -0400 Received: from mx2.redhat.com ([66.187.237.31]:48203 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758840AbZDGQgK (ORCPT ); Tue, 7 Apr 2009 12:36:10 -0400 Date: Tue, 7 Apr 2009 18:36:23 +0200 From: Michal Schmidt To: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Stephen Hemminger Subject: [PATCH] skge: fix occasional BUG during MTU change Message-ID: <20090407183623.7545bb0b@leela> Organization: Red Hat Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1846 Lines: 54 The BUG_ON(skge->tx_ring.to_use != skge->tx_ring.to_clean) in skge_up() was sometimes observed when setting MTU. skge_down() disables the TX queue, but then reenables it by mistake via skge_tx_clean(). Fix it by moving the waking of the queue from skge_tx_clean() to the other caller. And to make sure start_xmit is not in progress on another CPU, skge_down() should call netif_tx_disable(). The bug was reported to me by Jiri Jilek whose Debian system sometimes failed to boot. He tested the patch and the bug did not happen anymore. Signed-off-by: Michal Schmidt --- drivers/net/skge.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/skge.c b/drivers/net/skge.c index 952d37f..b2a05af 100644 --- a/drivers/net/skge.c +++ b/drivers/net/skge.c @@ -2674,7 +2674,7 @@ static int skge_down(struct net_device *dev) if (netif_msg_ifdown(skge)) printk(KERN_INFO PFX "%s: disabling interface\n", dev->name); - netif_stop_queue(dev); + netif_tx_disable(dev); if (hw->chip_id == CHIP_ID_GENESIS && hw->phy_type == SK_PHY_XMAC) del_timer_sync(&skge->link_timer); @@ -2881,7 +2881,6 @@ static void skge_tx_clean(struct net_device *dev) } skge->tx_ring.to_clean = e; - netif_wake_queue(dev); } static void skge_tx_timeout(struct net_device *dev) @@ -2893,6 +2892,7 @@ static void skge_tx_timeout(struct net_device *dev) skge_write8(skge->hw, Q_ADDR(txqaddr[skge->port], Q_CSR), CSR_STOP); skge_tx_clean(dev); + netif_wake_queue(dev); } static int skge_change_mtu(struct net_device *dev, int new_mtu) -- 1.6.2.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/