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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 83623C43331 for ; Sun, 10 Nov 2019 03:03:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4E8AE215EA for ; Sun, 10 Nov 2019 03:03:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573354998; bh=XO4jExzsjGqVGycvgNA7RUSP7N/Lq6fZtpDKT8aTcWE=; h=From:To:Cc:Subject:Date:List-ID:From; b=GAlQq8wlNoUrhsEoxq3fhp1KFqhmfvDal95rITaxdHwBPgVyy4PWB3Yq1Mm22FsXt 7a4ibtXzVtL77PmBRVWmiYWs2QmHADnYhTa9Brz2FtzDBDOq+ZXtctbWjuDzWpEDIK wNIMd7jTsqUuJFGd0OKsBdyqFIQuk/Cszl4d7Jjs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729314AbfKJCst (ORCPT ); Sat, 9 Nov 2019 21:48:49 -0500 Received: from mail.kernel.org ([198.145.29.99]:56552 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727984AbfKJCss (ORCPT ); Sat, 9 Nov 2019 21:48:48 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 3111C22573; Sun, 10 Nov 2019 02:48:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573354127; bh=XO4jExzsjGqVGycvgNA7RUSP7N/Lq6fZtpDKT8aTcWE=; h=From:To:Cc:Subject:Date:From; b=nS3GTpbVSU79UOfmOdapDWmuwF2+haTWnVM541S4JD+jvl6faBaLd3/uVsTcSB4c1 TYXtksx/NaTCA+DkRoNZL6NfeOsziAasRUAvnJIWGue+Mc+J6t1uiobsJ28I+ltC8A MBhQve/U373CldWdFSqIFKvnejtpD07YalyieLk4= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Julian Wiedmann , "David S . Miller" , Sasha Levin , linux-s390@vger.kernel.org Subject: [PATCH AUTOSEL 4.9 01/66] s390/qeth: invoke softirqs after napi_schedule() Date: Sat, 9 Nov 2019 21:47:40 -0500 Message-Id: <20191110024846.32598-1-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Julian Wiedmann [ Upstream commit 4d19db777a2f32c9b76f6fd517ed8960576cb43e ] Calling napi_schedule() from process context does not ensure that the NET_RX softirq is run in a timely fashion. So trigger it manually. This is no big issue with current code. A call to ndo_open() is usually followed by a ndo_set_rx_mode() call, and for qeth this contains a spin_unlock_bh(). Except for OSN, where qeth_l2_set_rx_mode() bails out early. Nevertheless it's best to not depend on this behaviour, and just fix the issue at its source like all other drivers do. For instance see commit 83a0c6e58901 ("i40e: Invoke softirqs after napi_reschedule"). Fixes: a1c3ed4c9ca0 ("qeth: NAPI support for l2 and l3 discipline") Signed-off-by: Julian Wiedmann Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/s390/net/qeth_l2_main.c | 3 +++ drivers/s390/net/qeth_l3_main.c | 3 +++ 2 files changed, 6 insertions(+) diff --git a/drivers/s390/net/qeth_l2_main.c b/drivers/s390/net/qeth_l2_main.c index 6ba4e921d2fd3..51152681aba6e 100644 --- a/drivers/s390/net/qeth_l2_main.c +++ b/drivers/s390/net/qeth_l2_main.c @@ -991,7 +991,10 @@ static int __qeth_l2_open(struct net_device *dev) if (qdio_stop_irq(card->data.ccwdev, 0) >= 0) { napi_enable(&card->napi); + local_bh_disable(); napi_schedule(&card->napi); + /* kick-start the NAPI softirq: */ + local_bh_enable(); } else rc = -EIO; return rc; diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c index 6e6ba1baf9c48..b40a61d9ad9ec 100644 --- a/drivers/s390/net/qeth_l3_main.c +++ b/drivers/s390/net/qeth_l3_main.c @@ -3005,7 +3005,10 @@ static int __qeth_l3_open(struct net_device *dev) if (qdio_stop_irq(card->data.ccwdev, 0) >= 0) { napi_enable(&card->napi); + local_bh_disable(); napi_schedule(&card->napi); + /* kick-start the NAPI softirq: */ + local_bh_enable(); } else rc = -EIO; return rc; -- 2.20.1