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=-16.1 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 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 65347C433F5 for ; Mon, 13 Sep 2021 05:55:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4B86F60E76 for ; Mon, 13 Sep 2021 05:55:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237318AbhIMF4R (ORCPT ); Mon, 13 Sep 2021 01:56:17 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:45173 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237273AbhIMF4P (ORCPT ); Mon, 13 Sep 2021 01:56:15 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1631512499; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=vR9iCzVCROKUiEXD2CzM4Pn1CySsVc/uXehQ5Tcbo98=; b=JXo4erVYeqstPOm+MN9JjSrKtF31uGkW0+hFxrfi5Uvsqve09cRi7iLozCwFjr6EfbqYJN X3bRtB1SuSY8UGEWcZUSGmkJI2SrrTnGt1UEMS1zZphgJVHyjefzObOILSXM5jdi8r7gvu ONQFdKv7Th+Vmenhbry0/FOcUjWPNf8= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-460-Ks-V8_G1NDe43t47inVZlQ-1; Mon, 13 Sep 2021 01:54:56 -0400 X-MC-Unique: Ks-V8_G1NDe43t47inVZlQ-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 740E6362F8; Mon, 13 Sep 2021 05:54:55 +0000 (UTC) Received: from localhost.localdomain (ovpn-13-146.pek2.redhat.com [10.72.13.146]) by smtp.corp.redhat.com (Postfix) with ESMTP id F0F1C17258; Mon, 13 Sep 2021 05:54:48 +0000 (UTC) From: Jason Wang To: mst@redhat.com, jasowang@redhat.com Cc: virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org, f.hetzelt@tu-berlin.de, david.kaplan@amd.com, konrad.wilk@oracle.com Subject: [PATCH 7/9] virtio-pci: harden INTX interrupts Date: Mon, 13 Sep 2021 13:53:51 +0800 Message-Id: <20210913055353.35219-8-jasowang@redhat.com> In-Reply-To: <20210913055353.35219-1-jasowang@redhat.com> References: <20210913055353.35219-1-jasowang@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch tries to make sure the virtio interrupt handler for INTX won't be called after a reset and before virtio_device_ready(). We can't use IRQF_NO_AUTOEN since we're using shared interrupt (IRQF_SHARED). So this patch tracks the INTX enabling status in a new intx_soft_enabled variable and toggle it during in vp_disable/enable_vectors(). The INTX interrupt handler will check intx_soft_enabled before processing the actual interrupt. Signed-off-by: Jason Wang --- drivers/virtio/virtio_pci_common.c | 18 ++++++++++++++++-- drivers/virtio/virtio_pci_common.h | 1 + 2 files changed, 17 insertions(+), 2 deletions(-) diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c index 0b9523e6dd39..835197151dc1 100644 --- a/drivers/virtio/virtio_pci_common.c +++ b/drivers/virtio/virtio_pci_common.c @@ -30,8 +30,12 @@ void vp_disable_vectors(struct virtio_device *vdev) struct virtio_pci_device *vp_dev = to_vp_device(vdev); int i; - if (vp_dev->intx_enabled) + if (vp_dev->intx_enabled) { + vp_dev->intx_soft_enabled = false; + /* ensure the vp_interrupt see this intx_soft_enabled value */ + smp_wmb(); synchronize_irq(vp_dev->pci_dev->irq); + } for (i = 0; i < vp_dev->msix_vectors; ++i) disable_irq(pci_irq_vector(vp_dev->pci_dev, i)); @@ -43,8 +47,12 @@ void vp_enable_vectors(struct virtio_device *vdev) struct virtio_pci_device *vp_dev = to_vp_device(vdev); int i; - if (vp_dev->intx_enabled) + if (vp_dev->intx_enabled) { + vp_dev->intx_soft_enabled = true; + /* ensure the vp_interrupt see this intx_soft_enabled value */ + smp_wmb(); return; + } for (i = 0; i < vp_dev->msix_vectors; ++i) enable_irq(pci_irq_vector(vp_dev->pci_dev, i)); @@ -97,6 +105,12 @@ static irqreturn_t vp_interrupt(int irq, void *opaque) struct virtio_pci_device *vp_dev = opaque; u8 isr; + if (!vp_dev->intx_soft_enabled) + return IRQ_NONE; + + /* read intx_soft_enabled before read others */ + smp_rmb(); + /* reading the ISR has the effect of also clearing it so it's very * important to save off the value. */ isr = ioread8(vp_dev->isr); diff --git a/drivers/virtio/virtio_pci_common.h b/drivers/virtio/virtio_pci_common.h index a235ce9ff6a5..3c06e0f92ee4 100644 --- a/drivers/virtio/virtio_pci_common.h +++ b/drivers/virtio/virtio_pci_common.h @@ -64,6 +64,7 @@ struct virtio_pci_device { /* MSI-X support */ int msix_enabled; int intx_enabled; + bool intx_soft_enabled; cpumask_var_t *msix_affinity_masks; /* Name strings for interrupts. This size should be enough, * and I'm too lazy to allocate each name separately. */ -- 2.25.1