From patchwork Tue Apr 2 15:00:10 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Cindy Lu X-Patchwork-Id: 13614278 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id CB6C4CD1284 for ; Tue, 2 Apr 2024 15:03:39 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rrfew-0002rJ-Gu; Tue, 02 Apr 2024 11:02:46 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rrfet-0002q7-Le for qemu-devel@nongnu.org; Tue, 02 Apr 2024 11:02:44 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rrfer-0000a6-Mk for qemu-devel@nongnu.org; Tue, 02 Apr 2024 11:02:43 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1712070158; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=pVdYP7lw33bCUp7E573yzbQERCgswbFMDLrv+gGeA78=; b=AEd/lCemKnNAHz76DlmZB2dasvhknetjQ2VPAg68V/4Zvf3cczduVUkjSlIcLxvyFZGRdr 1vufXNzl5HJznLGLkhhhaJTSRtI7UIthj36Rvvx3VVWR7PDvmaCfMtM4l/FnMAwL/HSI4R nsThUizF6fOfUlNgAmwwzTFOosG3JaU= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-563-EhSoGetBOGyULeQ7WV0sBA-1; Tue, 02 Apr 2024 11:02:36 -0400 X-MC-Unique: EhSoGetBOGyULeQ7WV0sBA-1 Received: from smtp.corp.redhat.com (int-mx10.intmail.prod.int.rdu2.redhat.com [10.11.54.10]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 76BA7101A523 for ; Tue, 2 Apr 2024 15:02:36 +0000 (UTC) Received: from server.redhat.com (unknown [10.72.112.166]) by smtp.corp.redhat.com (Postfix) with ESMTP id 61C65492BCD; Tue, 2 Apr 2024 15:02:34 +0000 (UTC) From: Cindy Lu To: lulu@redhat.com, mst@redhat.com, jasowang@redhat.com, qemu-devel@nongnu.org Subject: [PATCH 1/1] virtio-pci: Fix the crash when the vector changes back from VIRTIO_NO_VECTOR Date: Tue, 2 Apr 2024 23:00:10 +0800 Message-ID: <20240402150218.270587-2-lulu@redhat.com> In-Reply-To: <20240402150218.270587-1-lulu@redhat.com> References: <20240402150218.270587-1-lulu@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.10 Received-SPF: pass client-ip=170.10.129.124; envelope-from=lulu@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org When the guest calls virtio_stop and then virtio_reset, the vector will change to VIRTIO_NO_VECTOR and the IRQFD for this vector will be released. After that If you want to change the vector back, it will cause a crash. To fix this, we need to call the function "kvm_virtio_pci_vector_use_one()" when the vector changes back from VIRTIO_NO_VECTOR Signed-off-by: Cindy Lu --- hw/virtio/virtio-pci.c | 31 ++++++++++++++++++++++++++++--- 1 file changed, 28 insertions(+), 3 deletions(-) diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c index e433879542..45f3ab38c3 100644 --- a/hw/virtio/virtio-pci.c +++ b/hw/virtio/virtio-pci.c @@ -874,12 +874,14 @@ static int virtio_pci_get_notifier(VirtIOPCIProxy *proxy, int queue_no, return 0; } -static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no) +static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no, + bool recovery) { unsigned int vector; int ret; EventNotifier *n; PCIDevice *dev = &proxy->pci_dev; + VirtIOIRQFD *irqfd; VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus); VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); @@ -890,10 +892,21 @@ static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no) if (vector >= msix_nr_vectors_allocated(dev)) { return 0; } + /* + * if this is recovery and irqfd still in use, means the irqfd was not + * release before and don't need to set up again + */ + if (recovery) { + irqfd = &proxy->vector_irqfd[vector]; + if (irqfd->users != 0) { + return 0; + } + } ret = kvm_virtio_pci_vq_vector_use(proxy, vector); if (ret < 0) { goto undo; } + /* * If guest supports masking, set up irqfd now. * Otherwise, delay until unmasked in the frontend. @@ -932,14 +945,14 @@ static int kvm_virtio_pci_vector_vq_use(VirtIOPCIProxy *proxy, int nvqs) if (!virtio_queue_get_num(vdev, queue_no)) { return -1; } - ret = kvm_virtio_pci_vector_use_one(proxy, queue_no); + ret = kvm_virtio_pci_vector_use_one(proxy, queue_no, false); } return ret; } static int kvm_virtio_pci_vector_config_use(VirtIOPCIProxy *proxy) { - return kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX); + return kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX, false); } static void kvm_virtio_pci_vector_release_one(VirtIOPCIProxy *proxy, @@ -1570,7 +1583,13 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr, } else { val = VIRTIO_NO_VECTOR; } + vector = vdev->config_vector; vdev->config_vector = val; + /*check if the vector need to recovery*/ + if ((val != VIRTIO_NO_VECTOR) && (vector == VIRTIO_NO_VECTOR) && + (vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) { + kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX, true); + } break; case VIRTIO_PCI_COMMON_STATUS: if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) { @@ -1611,6 +1630,12 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr, val = VIRTIO_NO_VECTOR; } virtio_queue_set_vector(vdev, vdev->queue_sel, val); + + /*check if the vector need to recovery*/ + if ((val != VIRTIO_NO_VECTOR) && (vector == VIRTIO_NO_VECTOR) && + (vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) { + kvm_virtio_pci_vector_use_one(proxy, vdev->queue_sel, true); + } break; case VIRTIO_PCI_COMMON_Q_ENABLE: if (val == 1) {