From patchwork Mon Mar 1 16:12:07 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 390239 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=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, 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 1475BC4160E for ; Mon, 1 Mar 2021 16:30:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E07CC64D9E for ; Mon, 1 Mar 2021 16:30:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231381AbhCAQ3Z (ORCPT ); Mon, 1 Mar 2021 11:29:25 -0500 Received: from mail.kernel.org ([198.145.29.99]:59986 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234122AbhCAQZu (ORCPT ); Mon, 1 Mar 2021 11:25:50 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 1FB8964EBA; Mon, 1 Mar 2021 16:21:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1614615693; bh=zc8/ytEETcvvL6h2KmF8MxukwAdL0Q2MmX0tJSJc/dg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=wSGRqTx6bm6OBPy0gONx1HqgJVRDQqLP7xTzo32/MYdu4nKb2QjuG65ujPYuPD2Ct owx8ayOvh8/vaTRdrsp83BcCVCjgZIJD+tqjJxYfefydY6546q5kjmTUgqEFNy4j6a uhUEbzhPqPFsPYC5x1zsXc88NWsd+D0vmTIu3pjQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Juergen Gross , Jan Beulich , Paul Durrant , Wei Liu , "David S. Miller" , Sasha Levin Subject: [PATCH 4.9 026/134] xen/netback: fix spurious event detection for common event case Date: Mon, 1 Mar 2021 17:12:07 +0100 Message-Id: <20210301161014.857741370@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210301161013.585393984@linuxfoundation.org> References: <20210301161013.585393984@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Juergen Gross [ Upstream commit a3daf3d39132b405781be8d9ede0c449b244b64e ] In case of a common event for rx and tx queue the event should be regarded to be spurious if no rx and no tx requests are pending. Unfortunately the condition for testing that is wrong causing to decide a event being spurious if no rx OR no tx requests are pending. Fix that plus using local variables for rx/tx pending indicators in order to split function calls and if condition. Fixes: 23025393dbeb3b ("xen/netback: use lateeoi irq binding") Signed-off-by: Juergen Gross Reviewed-by: Jan Beulich Reviewed-by: Paul Durrant Reviewed-by: Wei Liu Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/xen-netback/interface.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c index e61073c751428..d9d06dc689edc 100644 --- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c @@ -161,13 +161,15 @@ irqreturn_t xenvif_interrupt(int irq, void *dev_id) { struct xenvif_queue *queue = dev_id; int old; + bool has_rx, has_tx; old = atomic_fetch_or(NETBK_COMMON_EOI, &queue->eoi_pending); WARN(old, "Interrupt while EOI pending\n"); - /* Use bitwise or as we need to call both functions. */ - if ((!xenvif_handle_tx_interrupt(queue) | - !xenvif_handle_rx_interrupt(queue))) { + has_tx = xenvif_handle_tx_interrupt(queue); + has_rx = xenvif_handle_rx_interrupt(queue); + + if (!has_rx && !has_tx) { atomic_andnot(NETBK_COMMON_EOI, &queue->eoi_pending); xen_irq_lateeoi(irq, XEN_EOI_FLAG_SPURIOUS); }