From patchwork Sat Nov 4 12:33:47 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 834189 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3yTdYF3lRlz9sPk for ; Sat, 4 Nov 2017 23:34:09 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932572AbdKDMeE (ORCPT ); Sat, 4 Nov 2017 08:34:04 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:52678 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752181AbdKDMeD (ORCPT ); Sat, 4 Nov 2017 08:34:03 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 0F84A1435; Sat, 4 Nov 2017 05:34:03 -0700 (PDT) Received: from why.lan (usa-sjc-mx-foss1.foss.arm.com [217.140.101.70]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id AF1D43F3E1; Sat, 4 Nov 2017 05:34:01 -0700 (PDT) From: Marc Zyngier To: Thomas Petazzoni , Antoine Tenart Cc: netdev@vger.kernel.org, "David S. Miller" , stable@vger.kernel.org Subject: [PATCH] net: mvpp2: Prevent userspace from changing TX affinities Date: Sat, 4 Nov 2017 12:33:47 +0000 Message-Id: <20171104123347.20540-1-marc.zyngier@arm.com> X-Mailer: git-send-email 2.11.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org The mvpp2 driver can't cope at all with the TX affinities being changed from userspace, and spit an endless stream of [ 91.779920] mvpp2 f4000000.ethernet eth2: wrong cpu on the end of Tx processing [ 91.779930] mvpp2 f4000000.ethernet eth2: wrong cpu on the end of Tx processing [ 91.780402] mvpp2 f4000000.ethernet eth2: wrong cpu on the end of Tx processing [ 91.780406] mvpp2 f4000000.ethernet eth2: wrong cpu on the end of Tx processing [ 91.780415] mvpp2 f4000000.ethernet eth2: wrong cpu on the end of Tx processing [ 91.780418] mvpp2 f4000000.ethernet eth2: wrong cpu on the end of Tx processing rendering the box completely useless (I've measured around 600k interrupts/s on a 8040 box) once irqbalance kicks in and start doing its job. Obviously, the driver was never designed with this in mind. So let's work around the problem by preventing userspace from interacting with these interrupts altogether. Cc: stable@vger.kernel.org Signed-off-by: Marc Zyngier --- drivers/net/ethernet/marvell/mvpp2.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/net/ethernet/marvell/mvpp2.c b/drivers/net/ethernet/marvell/mvpp2.c index a37af5813f33..fcf9ba5eb8d1 100644 --- a/drivers/net/ethernet/marvell/mvpp2.c +++ b/drivers/net/ethernet/marvell/mvpp2.c @@ -6747,6 +6747,9 @@ static int mvpp2_irqs_init(struct mvpp2_port *port) for (i = 0; i < port->nqvecs; i++) { struct mvpp2_queue_vector *qv = port->qvecs + i; + if (qv->type == MVPP2_QUEUE_VECTOR_PRIVATE) + irq_set_status_flags(qv->irq, IRQ_NO_BALANCING); + err = request_irq(qv->irq, mvpp2_isr, 0, port->dev->name, qv); if (err) goto err; @@ -6776,6 +6779,7 @@ static void mvpp2_irqs_deinit(struct mvpp2_port *port) struct mvpp2_queue_vector *qv = port->qvecs + i; irq_set_affinity_hint(qv->irq, NULL); + irq_clear_status_flags(qv->irq, IRQ_NO_BALANCING); free_irq(qv->irq, qv); } }