From mboxrd@z Thu Jan 1 00:00:00 1970 From: Roel Kluin Subject: [PATCH] pcmcia: worklimit reaches -1 Date: Wed, 25 Feb 2009 13:26:19 +0100 Message-ID: <49A538EB.8080008@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, linux-pcmcia@lists.infradead.org, Andrew Morton To: "David S. Miller" Return-path: Received: from yw-out-2324.google.com ([74.125.46.31]:11719 "EHLO yw-out-2324.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750784AbZBYM0W (ORCPT ); Wed, 25 Feb 2009 07:26:22 -0500 Received: by yw-out-2324.google.com with SMTP id 5so1325555ywh.1 for ; Wed, 25 Feb 2009 04:26:20 -0800 (PST) Sender: netdev-owner@vger.kernel.org List-ID: ------------------------------>8-------------8<--------------------------------- with while (--worklimit >= 0); worklimit reaches -1 after the loop. In 3c589_cs.c this caused a warning not to be printed. In 3c574_cs.c contrastingly, el3_rx() treats worklimit differently: static int el3_rx(struct net_device *dev, int worklimit) { while (--worklimit >= 0) { ... } return worklimit; } el3_rx() is only called by function el3_interrupt(): twice: static irqreturn_t el3_interrupt(int irq, void *dev_id) { int work_budget = max_interrupt_work; while(...) { if (...) work_budget = el3_rx(dev, work_budget); if (...) work_budget = el3_rx(dev, work_budget); if (--work_budget < 0) { ... break; } } } The error path can occur 2 too early. Signed-off-by: Roel Kluin --- el3_rx() calls: lines 839 and 856 el3_interrupt(): line 810 diff --git a/drivers/net/pcmcia/3c574_cs.c b/drivers/net/pcmcia/3c574_cs.c index e5cb6b1..2404a83 100644 --- a/drivers/net/pcmcia/3c574_cs.c +++ b/drivers/net/pcmcia/3c574_cs.c @@ -1035,7 +1035,8 @@ static int el3_rx(struct net_device *dev, int worklimit) DEBUG(3, "%s: in rx_packet(), status %4.4x, rx_status %4.4x.\n", dev->name, inw(ioaddr+EL3_STATUS), inw(ioaddr+RxStatus)); while (!((rx_status = inw(ioaddr + RxStatus)) & 0x8000) && - (--worklimit >= 0)) { + worklimit > 0) { + worklimit--; if (rx_status & 0x4000) { /* Error, update stats. */ short error = rx_status & 0x3800; dev->stats.rx_errors++; diff --git a/drivers/net/pcmcia/3c589_cs.c b/drivers/net/pcmcia/3c589_cs.c index 73ecc65..1e01b8a 100644 --- a/drivers/net/pcmcia/3c589_cs.c +++ b/drivers/net/pcmcia/3c589_cs.c @@ -857,7 +857,8 @@ static int el3_rx(struct net_device *dev) DEBUG(3, "%s: in rx_packet(), status %4.4x, rx_status %4.4x.\n", dev->name, inw(ioaddr+EL3_STATUS), inw(ioaddr+RX_STATUS)); while (!((rx_status = inw(ioaddr + RX_STATUS)) & 0x8000) && - (--worklimit >= 0)) { + worklimit > 0) { + worklimit--; if (rx_status & 0x4000) { /* Error, update stats. */ short error = rx_status & 0x3800; dev->stats.rx_errors++;