From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7AC50C04E53 for ; Wed, 15 May 2019 11:45:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4BDC1206BF for ; Wed, 15 May 2019 11:45:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557920728; bh=kXgHbfct4FOXsns1n39DH89GsG5ssCfDOBzqB+6qeIU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Kv9id43SRAEXNyxrT/edNY6OW7ZMH1QzVH8GquA1JRVviB6xa4zD8f8ciUVbcwChM c1JHNpoGS/gG9pi6RyKBZJDTuDM7JaIlEfMmH+2fUs6BSDVYJe6yQ4GyP/YaNftCxq wzszHx6SnoxWIPdl5hD70A5eGIokpmoMDMuQjNnk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732338AbfEOLp1 (ORCPT ); Wed, 15 May 2019 07:45:27 -0400 Received: from mail.kernel.org ([198.145.29.99]:36766 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732082AbfEOLZ5 (ORCPT ); Wed, 15 May 2019 07:25:57 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7013520818; Wed, 15 May 2019 11:25:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557919556; bh=kXgHbfct4FOXsns1n39DH89GsG5ssCfDOBzqB+6qeIU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=thMh7uqdpch/DuOUeRDNeKtWiCRq5fX7Nm5DaGgnIBUB2Dzvpk6jDiIKj0jOF30zI xbrnWlBpbrXwjCL6wm2HBgGSv1Rh3I2pUcbWKJsj0a3TCw6GPuVYDgChVBUoltykX7 9wjgm/EMv++HNGvlZ+XO3/jxmUupWFzauDxg6Nb8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Harini Katakam , Nicolas Ferre , "David S. Miller" Subject: [PATCH 4.19 095/113] net: macb: Change interrupt and napi enable order in open Date: Wed, 15 May 2019 12:56:26 +0200 Message-Id: <20190515090700.812315936@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190515090652.640988966@linuxfoundation.org> References: <20190515090652.640988966@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Harini Katakam [ Upstream commit 0504453139ef5a593c9587e1e851febee859c7d8 ] Current order in open: -> Enable interrupts (macb_init_hw) -> Enable NAPI -> Start PHY Sequence of RX handling: -> RX interrupt occurs -> Interrupt is cleared and interrupt bits disabled in handler -> NAPI is scheduled -> In NAPI, RX budget is processed and RX interrupts are re-enabled With the above, on QEMU or fixed link setups (where PHY state doesn't matter), there's a chance macb RX interrupt occurs before NAPI is enabled. This will result in NAPI being scheduled before it is enabled. Fix this macb open by changing the order. Fixes: ae1f2a56d273 ("net: macb: Added support for many RX queues") Signed-off-by: Harini Katakam Acked-by: Nicolas Ferre Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/cadence/macb_main.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/drivers/net/ethernet/cadence/macb_main.c +++ b/drivers/net/ethernet/cadence/macb_main.c @@ -2419,12 +2419,12 @@ static int macb_open(struct net_device * return err; } - bp->macbgem_ops.mog_init_rings(bp); - macb_init_hw(bp); - for (q = 0, queue = bp->queues; q < bp->num_queues; ++q, ++queue) napi_enable(&queue->napi); + bp->macbgem_ops.mog_init_rings(bp); + macb_init_hw(bp); + /* schedule a link state check */ phy_start(dev->phydev);