From patchwork Wed Jun 27 11:25:20 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pankaj Gupta X-Patchwork-Id: 10491165 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 2A519602B3 for ; Wed, 27 Jun 2018 11:26:29 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2B76A283B1 for ; Wed, 27 Jun 2018 11:26:26 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 1ECE02899B; Wed, 27 Jun 2018 11:26:26 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id BE93C283B1 for ; Wed, 27 Jun 2018 11:26:25 +0000 (UTC) Received: from localhost ([::1]:58209 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fY8af-0005GJ-1F for patchwork-qemu-devel@patchwork.kernel.org; Wed, 27 Jun 2018 07:26:25 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:55825) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fY8Zm-0004g6-5O for qemu-devel@nongnu.org; Wed, 27 Jun 2018 07:25:31 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fY8Zh-0004po-6Q for qemu-devel@nongnu.org; Wed, 27 Jun 2018 07:25:30 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:48222 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fY8Zg-0004oV-Tu for qemu-devel@nongnu.org; Wed, 27 Jun 2018 07:25:25 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 78879401C96B; Wed, 27 Jun 2018 11:25:24 +0000 (UTC) Received: from dhcp201-121.englab.pnq.redhat.com (ovpn-117-31.sin2.redhat.com [10.67.117.31]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3C0E22026D5B; Wed, 27 Jun 2018 11:25:21 +0000 (UTC) From: Pankaj Gupta To: mst@redhat.com, amit@kernel.org, qemu-devel@nongnu.org Date: Wed, 27 Jun 2018 16:55:20 +0530 Message-Id: <20180627112520.26085-1-pagupta@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.5]); Wed, 27 Jun 2018 11:25:24 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.5]); Wed, 27 Jun 2018 11:25:24 +0000 (UTC) for IP:'10.11.54.4' DOMAIN:'int-mx04.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'pagupta@redhat.com' RCPT:'' X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 66.187.233.73 Subject: [Qemu-devel] [PATCH v2] virtio-rng: process pending requests when driver is ready 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: slopezpa@redhat.com, stefanha@redhat.com Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP virtio-rng device causing old guest kernels(2.6.32) to hang on latest qemu. The driver attempts to read from the virtio-rng device too early in it's initialization. Qemu detects guest is not ready and returns, resulting in hang. Fix is to handle pending request when guest is running and driver status is set to 'VIRTIO_CONFIG_S_DRIVER_OK'. Reported-by: Sergio lopez Signed-off-by: Stefan Hajnoczi Signed-off-by: Pankaj Gupta --- v1->v2: Update new status value early only for virtio-rng (Stefan) hw/virtio/virtio-rng.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/hw/virtio/virtio-rng.c b/hw/virtio/virtio-rng.c index 289bbcac03..855f1b41d1 100644 --- a/hw/virtio/virtio-rng.c +++ b/hw/virtio/virtio-rng.c @@ -156,6 +156,19 @@ static void check_rate_limit(void *opaque) vrng->activate_timer = true; } +static void virtio_rng_set_status(VirtIODevice *vdev, uint8_t status) +{ + VirtIORNG *vrng = VIRTIO_RNG(vdev); + + if (!vdev->vm_running) { + return; + } + vdev->status = status; + + /* Something changed, try to process buffers */ + virtio_rng_process(vrng); +} + static void virtio_rng_device_realize(DeviceState *dev, Error **errp) { VirtIODevice *vdev = VIRTIO_DEVICE(dev); @@ -261,6 +274,7 @@ static void virtio_rng_class_init(ObjectClass *klass, void *data) vdc->realize = virtio_rng_device_realize; vdc->unrealize = virtio_rng_device_unrealize; vdc->get_features = get_features; + vdc->set_status = virtio_rng_set_status; } static const TypeInfo virtio_rng_info = {