From patchwork Mon Mar 1 16:12:30 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 390290 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 7F9E2C433E0 for ; Mon, 1 Mar 2021 16:19:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 26CEA64EEA for ; Mon, 1 Mar 2021 16:19:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237719AbhCAQSw (ORCPT ); Mon, 1 Mar 2021 11:18:52 -0500 Received: from mail.kernel.org ([198.145.29.99]:56660 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237650AbhCAQSn (ORCPT ); Mon, 1 Mar 2021 11:18:43 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id C224364E42; Mon, 1 Mar 2021 16:16:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1614615406; bh=pf5dxNPqDLI7+f64QbwgKr8oGcKQU6nm7fopCWhpbR4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=1xhF5wV2Qm9neJBu3OSZvje7x5pi65D23fofmqiyAiNyoXIKx+5SHlMDwVcIRwEKa 0kqWgoa4NffjZ6hynirGMXcRz+LUzRbLA63A1UfGNNiDFnL1PG//Tcx+HKEvObCxH3 Zew7/+m2+G2kiJ9zLboS3SNyLvOzqJkT3DUthvZo= 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 4.4 18/93] xen/netback: fix spurious event detection for common event case Date: Mon, 1 Mar 2021 17:12:30 +0100 Message-Id: <20210301161007.792328870@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210301161006.881950696@linuxfoundation.org> References: <20210301161006.881950696@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 f9f4391ecee37..93f7659e75954 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 = xenvif_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); }