From nobody Mon Nov 25 07:22:46 2024 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1716354744; cv=none; d=zohomail.com; s=zohoarc; b=IFDyjDHkgjSAXLSsYVMaxqqWgAvGWdagM6yUvyQlpZERNQDMNoIBMNlbvndlXBELFVzN64UiIPiRF4Hb5LAojN/TRLTq/Xi4UaCunWkBiNDTQfG0hbIv+PCkkgYPBElhv8vVsVWNV+beHJaeEPiQSxVaUr0hd8wRVcpWp/D9axw= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1716354744; h=Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:Sender:Subject:Subject:To:To:Message-Id:Reply-To; bh=rm7JFyuekwYkGdiZNv6/FbnOeDGJ/2t3JnDhFmq8++8=; b=QS/0SMscvZVwsblEtrjOPUziigajzG36/tWmYwvc5uZGRwcBuRow62VyU02gdYKwUpBgwA8QP8R+KabB02GVzuMnSYanemyVxT6zwuIO5ZT9iMwQwhJfzluj0vervlO08EtB5ndEt4rEyDjSHvnf4jQ0yNSr/x3hGizWZ+tvHAs= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass header.from= (p=none dis=none) Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 171635474401867.38964971199835; Tue, 21 May 2024 22:12:24 -0700 (PDT) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1s9eFd-0006QK-Kq; Wed, 22 May 2024 01:10:57 -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 1s9eFb-0006PN-N2 for qemu-devel@nongnu.org; Wed, 22 May 2024 01:10:55 -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 1s9eFZ-0002XI-TN for qemu-devel@nongnu.org; Wed, 22 May 2024 01:10:55 -0400 Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-175-hE1NQZIrOuOS6ZVB-yAiUA-1; Wed, 22 May 2024 01:10:49 -0400 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 5C1873806739; Wed, 22 May 2024 05:10:49 +0000 (UTC) Received: from server.redhat.com (unknown [10.72.112.57]) by smtp.corp.redhat.com (Postfix) with ESMTP id B55B240004D; Wed, 22 May 2024 05:10:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1716354653; 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=rm7JFyuekwYkGdiZNv6/FbnOeDGJ/2t3JnDhFmq8++8=; b=faNeOUGaPUjc79XmR3VPXjTb7KdM5WZ7iQFKWmMm5dxIv6QwlTChlmTgmFa4BaVe++0bT8 itBQERtFJiEgY9KVvsjiyKO2bkXJrGEnKUSz/cdMdd+bUr6GRMXIeiALfjc6eFt3fEmNbw A5DUbHfuIJ1u+syxDKX/kKcFmyG1wbQ= X-MC-Unique: hE1NQZIrOuOS6ZVB-yAiUA-1 From: Cindy Lu To: lulu@redhat.com, mst@redhat.com, jasowang@redhat.com, qemu-devel@nongnu.org Cc: qemu-stable@nongnu.org Subject: [PATCH] virtio-pci: Fix the use of an uninitialized irqfd. Date: Wed, 22 May 2024 13:10:24 +0800 Message-ID: <20240522051042.985825-1-lulu@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.10 Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; 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=unavailable 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+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZohoMail-DKIM: pass (identity @redhat.com) X-ZM-MESSAGEID: 1716354745798100001 Content-Type: text/plain; charset="utf-8" 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 that the function virtio_pci_set_guest_notifiers() only initializes the irqfd when the use_guest_notifier_mask and guest_notifier_m= ask are set. However, this check is missing in virtio_pci_set_vector(). So the fix is to add this check. 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 =3D=3D 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/s= ystem/memory.c:497 3 0x0000598365704ba6 in access_with_adjusted_size () at ../qemu-9.0.0/syst= em/memory.c:573 4 0x0000598365705059 in memory_region_dispatch_write () at ../qemu-9.0.0/s= ystem/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/phy= smem.c:2894 9 0x0000598365763afe in address_space_rw () at ../qemu-9.0.0/system/physme= m.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/k= vm-accel-ops.c:50 12 0x0000598365926ca8 in qemu_thread_start () at ../qemu-9.0.0/util/qemu-th= read-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 Acked-by: Jason Wang --- hw/virtio/virtio-pci.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c index b1d02f4b3d..a7faee5b33 100644 --- a/hw/virtio/virtio-pci.c +++ b/hw/virtio/virtio-pci.c @@ -1431,6 +1431,7 @@ static void virtio_pci_set_vector(VirtIODevice *vdev, { bool kvm_irqfd =3D (vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) && msix_enabled(&proxy->pci_dev) && kvm_msi_via_irqfd_enabled(); + VirtioDeviceClass *k =3D VIRTIO_DEVICE_GET_CLASS(vdev); =20 if (new_vector =3D=3D old_vector) { return; @@ -1441,7 +1442,8 @@ static void virtio_pci_set_vector(VirtIODevice *vdev, * set, we need to release the old vector and set up the new one. * Otherwise just need to set the new vector on the device. */ - if (kvm_irqfd && old_vector !=3D VIRTIO_NO_VECTOR) { + if (kvm_irqfd && old_vector !=3D VIRTIO_NO_VECTOR && + vdev->use_guest_notifier_mask && k->guest_notifier_mask) { kvm_virtio_pci_vector_release_one(proxy, queue_no); } /* Set the new vector on the device. */ @@ -1451,7 +1453,8 @@ static void virtio_pci_set_vector(VirtIODevice *vdev, virtio_queue_set_vector(vdev, queue_no, new_vector); } /* If the new vector changed need to set it up. */ - if (kvm_irqfd && new_vector !=3D VIRTIO_NO_VECTOR) { + if (kvm_irqfd && new_vector !=3D VIRTIO_NO_VECTOR && + vdev->use_guest_notifier_mask && k->guest_notifier_mask) { kvm_virtio_pci_vector_use_one(proxy, queue_no); } } --=20 2.43.0