From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id C9C8EDDED1 for ; Tue, 24 Jun 2008 09:20:27 +1000 (EST) Subject: Re: [PATCH] ibm_newemac: Fixes kernel crashes when speed of cable connected changes From: Benjamin Herrenschmidt To: Stefan Roese In-Reply-To: <1214225694-25815-1-git-send-email-sr@denx.de> References: <1214225694-25815-1-git-send-email-sr@denx.de> Content-Type: text/plain Date: Tue, 24 Jun 2008 09:20:16 +1000 Message-Id: <1214263216.8011.276.camel@pasglop> Mime-Version: 1.0 Cc: linuxppc-dev@ozlabs.org, Sathya Narayanan , netdev@vger.kernel.org Reply-To: benh@kernel.crashing.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Mon, 2008-06-23 at 14:54 +0200, Stefan Roese wrote: > From: Sathya Narayanan > > The descriptor pointers were not initialized to NIL values, so it was > poiniting to some random addresses which was completely invalid. This > fix takes care of initializing the descriptor to NIL values and clearing > the valid descriptors on clean ring operation. > > Signed-off-by: Sathya Narayanan > Signed-off-by: Stefan Roese > --- > drivers/net/ibm_newemac/core.c | 6 +++++- > 1 files changed, 5 insertions(+), 1 deletions(-) > > diff --git a/drivers/net/ibm_newemac/core.c b/drivers/net/ibm_newemac/core.c > index 5d2108c..6dfc2c9 100644 > --- a/drivers/net/ibm_newemac/core.c > +++ b/drivers/net/ibm_newemac/core.c > @@ -1025,7 +1025,7 @@ static void emac_clean_tx_ring(struct emac_instance *dev) > int i; > > for (i = 0; i < NUM_TX_BUFF; ++i) { > - if (dev->tx_skb[i]) { > + if (dev->tx_skb[i] && dev->tx_desc[i].data_ptr) { Why changing the test above ? > dev_kfree_skb(dev->tx_skb[i]); > dev->tx_skb[i] = NULL; > if (dev->tx_desc[i].ctrl & MAL_TX_CTRL_READY) > @@ -2719,6 +2719,10 @@ static int __devinit emac_probe(struct of_device *ofdev, > /* Clean rings */ > memset(dev->tx_desc, 0, NUM_TX_BUFF * sizeof(struct mal_descriptor)); > memset(dev->rx_desc, 0, NUM_RX_BUFF * sizeof(struct mal_descriptor)); > + for (i = 0; i <= NUM_TX_BUFF; i++) > + dev->tx_skb[i] = NULL; > + for (i = 0; i <= NUM_RX_BUFF; i++) > + dev->rx_skb[i] = NULL; Why not use memset here too ? > /* Attach to ZMII, if needed */ > if (emac_has_feature(dev, EMAC_FTR_HAS_ZMII) &&