From nobody Fri Dec 19 18:41:53 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1537932708288630.3117052030157; Tue, 25 Sep 2018 20:31:48 -0700 (PDT) Received: from localhost ([::1]:56234 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1g50YF-00012j-4G for importer@patchew.org; Tue, 25 Sep 2018 23:31:47 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:55892) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1g50Sl-0004gE-Pz for qemu-devel@nongnu.org; Tue, 25 Sep 2018 23:26:10 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1g50L2-0002hI-11 for qemu-devel@nongnu.org; Tue, 25 Sep 2018 23:18:11 -0400 Received: from mx1.redhat.com ([209.132.183.28]:57590) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1g50L1-0002gv-Rf; Tue, 25 Sep 2018 23:18:07 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id E18D930842D0; Wed, 26 Sep 2018 03:18:06 +0000 (UTC) Received: from jason-ThinkPad-T450s.redhat.com (ovpn-12-161.pek2.redhat.com [10.72.12.161]) by smtp.corp.redhat.com (Postfix) with ESMTP id 65C1860BE1; Wed, 26 Sep 2018 03:18:04 +0000 (UTC) From: Jason Wang To: qemu-devel@nongnu.org Date: Wed, 26 Sep 2018 11:16:45 +0800 Message-Id: <20180926031650.8892-21-jasowang@redhat.com> In-Reply-To: <20180926031650.8892-1-jasowang@redhat.com> References: <20180926031650.8892-1-jasowang@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.40]); Wed, 26 Sep 2018 03:18:06 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PULL 20/25] clean up callback when del virtqueue X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: peter.maydell@linaro.org, Jason Wang , qemu-stable@nongnu.org, liujunjie Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RDMRC_1 RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" From: liujunjie Before, we did not clear callback like handle_output when delete the virtqueue which may result be segmentfault. The scene is as follows: 1. Start a vm with multiqueue vhost-net, 2. then we write VIRTIO_PCI_GUEST_FEATURES in PCI configuration to triger multiqueue disable in this vm which will delete the virtqueue. In this step, the tx_bh is deleted but the callback virtio_net_handle_tx_bh still exist. 3. Finally, we write VIRTIO_PCI_QUEUE_NOTIFY in PCI configuration to notify the deleted virtqueue. In this way, virtio_net_handle_tx_bh will be called and qemu will be crashed. Although the way described above is uncommon, we had better reinforce it. CC: qemu-stable@nongnu.org Signed-off-by: liujunjie Signed-off-by: Jason Wang --- hw/virtio/virtio.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index f6a588ab57..57a603a65b 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -1604,6 +1604,8 @@ void virtio_del_queue(VirtIODevice *vdev, int n) =20 vdev->vq[n].vring.num =3D 0; vdev->vq[n].vring.num_default =3D 0; + vdev->vq[n].handle_output =3D NULL; + vdev->vq[n].handle_aio_output =3D NULL; } =20 static void virtio_set_isr(VirtIODevice *vdev, int value) --=20 2.17.1