From patchwork Thu Dec 19 11:13:09 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Leigh Brown X-Patchwork-Id: 3376751 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 56293C0D4A for ; Thu, 19 Dec 2013 11:14:02 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 8D4A520640 for ; Thu, 19 Dec 2013 11:13:57 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id C870020639 for ; Thu, 19 Dec 2013 11:13:52 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1VtbY3-0005GJ-Fo; Thu, 19 Dec 2013 11:13:47 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1VtbY0-0003o1-Vp; Thu, 19 Dec 2013 11:13:45 +0000 Received: from doppler.thel33t.co.uk ([193.110.88.198]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1VtbXx-0003mb-AR for linux-arm-kernel@lists.infradead.org; Thu, 19 Dec 2013 11:13:42 +0000 Received: from dish.dyn.solinno.co.uk. (82-68-130-54.dsl.in-addr.zen.co.uk [82.68.130.54]) by doppler.thel33t.co.uk (Postfix) with ESMTPSA id CEA5E840B4; Thu, 19 Dec 2013 11:20:22 +0000 (GMT) From: Leigh Brown To: "David S. Miller" Subject: [PATCH] net: mvmdio: fix interrupt timeout handling Date: Thu, 19 Dec 2013 11:13:09 +0000 Message-Id: <1387451589-15491-1-git-send-email-leigh@solinno.co.uk> X-Mailer: git-send-email 1.8.5.1 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20131219_061341_450050_CEDAA484 X-CRM114-Status: GOOD ( 10.91 ) X-Spam-Score: -1.9 (-) Cc: Russell King - ARM Linux , Jason Cooper , Nicolas Schichan , netdev@vger.kernel.org, LKML , Leigh Brown , Florian Fainelli , linux-arm-kernel@lists.infradead.org, Sebastian Hesselbarth X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.7 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP orion_mdio_wait_ready uses wait_event_timeout to wait for the SMI interrupt to fire. wait_event_timeout waits for between "timeout - 1" and "timeout" jiffies. In this case a 1ms timeout when HZ is 1000 results in a wait of 0 to 1 jiffies, causing premature timeouts. This fix ensures a minimum timeout of 2 jiffies, ensuring wait_event_timeout will always wait at least 1 jiffie. Issue reported by Nicolas Schichan. Tested-by: Nicolas Schichan Signed-off-by: Leigh Brown --- drivers/net/ethernet/marvell/mvmdio.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/net/ethernet/marvell/mvmdio.c b/drivers/net/ethernet/marvell/mvmdio.c index 7354960..a42a750 100644 --- a/drivers/net/ethernet/marvell/mvmdio.c +++ b/drivers/net/ethernet/marvell/mvmdio.c @@ -92,6 +92,12 @@ static int orion_mdio_wait_ready(struct mii_bus *bus) if (time_is_before_jiffies(end)) ++timedout; } else { + /* wait_event_timeout does not guarantee a delay of at + * least one whole jiffie, so timeout must be no less + * than two. + */ + if (timeout < 2) + timeout = 2; wait_event_timeout(dev->smi_busy_wait, orion_mdio_smi_is_done(dev), timeout);