From patchwork Mon Jun 17 09:55:11 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Cindy Lu X-Patchwork-Id: 13700457 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 1BCE3C2BA18 for ; Mon, 17 Jun 2024 09:56:17 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1sJ95h-0001Wv-Dn; Mon, 17 Jun 2024 05:55:57 -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 1sJ95Z-0001Vm-84 for qemu-devel@nongnu.org; Mon, 17 Jun 2024 05:55:50 -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 1sJ95V-0003nl-NI for qemu-devel@nongnu.org; Mon, 17 Jun 2024 05:55:48 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1718618144; 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; bh=Qe7R8H5cl+HNN2ev9m8EA5o6I9TdKdsTYBDRk7rZ3JI=; b=G+WclVaYcwaR6p7h74SSKc8I8u1M/0lIb3t46t7BXHpW5yEuPF43zulOokUKUICJ4+mIYh Cmw+jbYgFhdtQ3X1+FXdxDEIW2QDITFFLWC+/28vGLV+3rIiesrwKyNfVg88pRmHW8o28W 3mgDBsJiYk15RAD1vUauEm7WJz5FT18= Received: from mx-prod-mc-02.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-677-rkxLPNC_MWyb48hqNcPzEw-1; Mon, 17 Jun 2024 05:55:40 -0400 X-MC-Unique: rkxLPNC_MWyb48hqNcPzEw-1 Received: from mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.40]) (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 mx-prod-mc-02.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 6BF4B19560AF; Mon, 17 Jun 2024 09:55:39 +0000 (UTC) Received: from server.redhat.com (unknown [10.72.112.124]) by mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 1E78A1956087; Mon, 17 Jun 2024 09:55:34 +0000 (UTC) From: Cindy Lu To: lulu@redhat.com, mst@redhat.com, jasowang@redhat.com, qemu-devel@nongnu.org Cc: qemu-stable@nongnu.org Subject: [PATCH v2] virtio-pci: Fix the use of an uninitialized irqfd. Date: Mon, 17 Jun 2024 17:55:11 +0800 Message-ID: <20240617095529.115046-1-lulu@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.0 on 10.30.177.40 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: 11 X-Spam_score: 1.1 X-Spam_bar: + X-Spam_report: (1.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.148, 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=-0.01, RCVD_IN_MSPIKE_WL=-0.01, RCVD_IN_SBL_CSS=3.335, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=no 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 The crash was reported in MAC OS and NixOS, here is the link for this bug https://gitlab.com/qemu-project/qemu/-/issues/2334 https://gitlab.com/qemu-project/qemu/-/issues/2321 The root cause is the function virtio_pci_set_guest_notifiers() was not called in the virtio_input device.So the vector_irqfd was not initialized So the fix is to add the check for vector_irqfd. This fix is verified in vyatta,MacOS,NixOS,fedora system. The bt tree for this bug is: Thread 6 "CPU 0/KVM" received signal SIGSEGV, Segmentation fault. [Switching to Thread 0x7c817be006c0 (LWP 1269146)] kvm_virtio_pci_vq_vector_use () at ../qemu-9.0.0/hw/virtio/virtio-pci.c:817 817 if (irqfd->users == 0) { (gdb) thread apply all bt ... Thread 6 (Thread 0x7c817be006c0 (LWP 1269146) "CPU 0/KVM"): 0 kvm_virtio_pci_vq_vector_use () at ../qemu-9.0.0/hw/virtio/virtio-pci.c:817 1 kvm_virtio_pci_vector_use_one () at ../qemu-9.0.0/hw/virtio/virtio-pci.c:893 2 0x00005983657045e2 in memory_region_write_accessor () at ../qemu-9.0.0/system/memory.c:497 3 0x0000598365704ba6 in access_with_adjusted_size () at ../qemu-9.0.0/system/memory.c:573 4 0x0000598365705059 in memory_region_dispatch_write () at ../qemu-9.0.0/system/memory.c:1528 5 0x00005983659b8e1f in flatview_write_continue_step.isra.0 () at ../qemu-9.0.0/system/physmem.c:2713 6 0x000059836570ba7d in flatview_write_continue () at ../qemu-9.0.0/system/physmem.c:2743 7 flatview_write () at ../qemu-9.0.0/system/physmem.c:2774 8 0x000059836570bb76 in address_space_write () at ../qemu-9.0.0/system/physmem.c:2894 9 0x0000598365763afe in address_space_rw () at ../qemu-9.0.0/system/physmem.c:2904 10 kvm_cpu_exec () at ../qemu-9.0.0/accel/kvm/kvm-all.c:2917 11 0x000059836576656e in kvm_vcpu_thread_fn () at ../qemu-9.0.0/accel/kvm/kvm-accel-ops.c:50 12 0x0000598365926ca8 in qemu_thread_start () at ../qemu-9.0.0/util/qemu-thread-posix.c:541 13 0x00007c8185bcd1cf in ??? () at /usr/lib/libc.so.6 14 0x00007c8185c4e504 in clone () at /usr/lib/libc.so.6 Fixes: 2ce6cff94d ("virtio-pci: fix use of a released vector") Cc: qemu-stable@nongnu.org Signed-off-by: Cindy Lu --- hw/virtio/virtio-pci.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c index b1d02f4b3d..502aad28b2 100644 --- a/hw/virtio/virtio-pci.c +++ b/hw/virtio/virtio-pci.c @@ -1442,7 +1442,9 @@ static void virtio_pci_set_vector(VirtIODevice *vdev, * Otherwise just need to set the new vector on the device. */ if (kvm_irqfd && old_vector != VIRTIO_NO_VECTOR) { - kvm_virtio_pci_vector_release_one(proxy, queue_no); + if (proxy->vector_irqfd) { + kvm_virtio_pci_vector_release_one(proxy, queue_no); + } } /* Set the new vector on the device. */ if (queue_no == VIRTIO_CONFIG_IRQ_IDX) { @@ -1452,7 +1454,9 @@ static void virtio_pci_set_vector(VirtIODevice *vdev, } /* If the new vector changed need to set it up. */ if (kvm_irqfd && new_vector != VIRTIO_NO_VECTOR) { - kvm_virtio_pci_vector_use_one(proxy, queue_no); + if (proxy->vector_irqfd) { + kvm_virtio_pci_vector_use_one(proxy, queue_no); + } } }