From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 92D13C433E0 for ; Tue, 28 Jul 2020 03:56:15 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 51E2E20759 for ; Tue, 28 Jul 2020 03:56:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="iYkzFMqP" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 51E2E20759 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:44998 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1k0Gis-00033h-Im for qemu-devel@archiver.kernel.org; Mon, 27 Jul 2020 23:56:14 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:53612) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1k0GiD-0002XL-Aq for qemu-devel@nongnu.org; Mon, 27 Jul 2020 23:55:33 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:39955 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1k0GiA-0008ID-9e for qemu-devel@nongnu.org; Mon, 27 Jul 2020 23:55:32 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1595908528; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ynpCO4uyr/8A3lGbL6JNSrbQSI0Cz1oD4mjLWJYAXDI=; b=iYkzFMqPxC2V7Hr6DS0jkQ6hIFVTr9K8D5gI0cH/YOVXCScoVdpvydLGpkPzwxRX2Ard5M lOCqSzVL2XAIinYqHD2e1Et9VKoL9Bc11xnmT02N8t3DoIHADAt17ycWvY5+iOBBZ/62Gd BtohhMs8gR7+9Bz1MxX/o6kNouYdIDk= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-433-8oe0LFtfNSGjyKLsikHQZw-1; Mon, 27 Jul 2020 23:55:26 -0400 X-MC-Unique: 8oe0LFtfNSGjyKLsikHQZw-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id F41D9186A835 for ; Tue, 28 Jul 2020 03:55:25 +0000 (UTC) Received: from [10.72.13.242] (ovpn-13-242.pek2.redhat.com [10.72.13.242]) by smtp.corp.redhat.com (Postfix) with ESMTP id 05F8D726BE; Tue, 28 Jul 2020 03:55:17 +0000 (UTC) Subject: Re: [PATCH] virtio-pci: fix virtio_pci_queue_enabled() To: Laurent Vivier , qemu-devel@nongnu.org References: <20200727153319.43716-1-lvivier@redhat.com> From: Jason Wang Message-ID: Date: Tue, 28 Jul 2020 11:55:16 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20200727153319.43716-1-lvivier@redhat.com> Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=207.211.31.120; envelope-from=jasowang@redhat.com; helo=us-smtp-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/07/27 23:55:28 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -30 X-Spam_score: -3.1 X-Spam_bar: --- X-Spam_report: (-3.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1, 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_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, 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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Cindy Lu , "Michael S. Tsirkin" Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 2020/7/27 下午11:33, Laurent Vivier wrote: > In legacy mode, virtio_pci_queue_enabled() falls back to > virtio_queue_enabled() to know if the queue is enabled. > > But virtio_queue_enabled() calls again virtio_pci_queue_enabled() > if k->queue_enabled is set. This ends in a crash after a stack > overflow. > > The problem can be reproduced with > "-device virtio-net-pci,disable-legacy=off,disable-modern=true > -net tap,vhost=on" > > And a look to the backtrace is very explicit: > > ... > #4 0x000000010029a438 in virtio_queue_enabled () > #5 0x0000000100497a9c in virtio_pci_queue_enabled () > ... > #130902 0x000000010029a460 in virtio_queue_enabled () > #130903 0x0000000100497a9c in virtio_pci_queue_enabled () > #130904 0x000000010029a460 in virtio_queue_enabled () > #130905 0x0000000100454a20 in vhost_net_start () > ... > > This patch fixes the problem by introducing a new function > for the legacy case and calls it from virtio_pci_queue_enabled(). > It also calls it from virtio_queue_enabled() to avoid code duplication. > > Fixes: f19bcdfedd53 ("virtio-pci: implement queue_enabled method") > Cc: Jason Wang > Cc: Cindy Lu > CC: Michael S. Tsirkin > Signed-off-by: Laurent Vivier Queued for rc2. Thanks > --- > hw/virtio/virtio-pci.c | 2 +- > hw/virtio/virtio.c | 7 ++++++- > include/hw/virtio/virtio.h | 1 + > 3 files changed, 8 insertions(+), 2 deletions(-) > > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c > index ada1101d07bf..4ad3ad81a2cf 100644 > --- a/hw/virtio/virtio-pci.c > +++ b/hw/virtio/virtio-pci.c > @@ -1116,7 +1116,7 @@ static bool virtio_pci_queue_enabled(DeviceState *d, int n) > return proxy->vqs[vdev->queue_sel].enabled; > } > > - return virtio_queue_enabled(vdev, n); > + return virtio_queue_enabled_legacy(vdev, n); > } > > static int virtio_pci_add_mem_cap(VirtIOPCIProxy *proxy, > diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c > index 546a198e79b0..e98302521769 100644 > --- a/hw/virtio/virtio.c > +++ b/hw/virtio/virtio.c > @@ -3309,6 +3309,11 @@ hwaddr virtio_queue_get_desc_addr(VirtIODevice *vdev, int n) > return vdev->vq[n].vring.desc; > } > > +bool virtio_queue_enabled_legacy(VirtIODevice *vdev, int n) > +{ > + return virtio_queue_get_desc_addr(vdev, n) != 0; > +} > + > bool virtio_queue_enabled(VirtIODevice *vdev, int n) > { > BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); > @@ -3317,7 +3322,7 @@ bool virtio_queue_enabled(VirtIODevice *vdev, int n) > if (k->queue_enabled) { > return k->queue_enabled(qbus->parent, n); > } > - return virtio_queue_get_desc_addr(vdev, n) != 0; > + return virtio_queue_enabled_legacy(vdev, n); > } > > hwaddr virtio_queue_get_avail_addr(VirtIODevice *vdev, int n) > diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h > index 198ffc762678..e424df12cf6d 100644 > --- a/include/hw/virtio/virtio.h > +++ b/include/hw/virtio/virtio.h > @@ -295,6 +295,7 @@ typedef struct VirtIORNGConf VirtIORNGConf; > VIRTIO_F_RING_PACKED, false) > > hwaddr virtio_queue_get_desc_addr(VirtIODevice *vdev, int n); > +bool virtio_queue_enabled_legacy(VirtIODevice *vdev, int n); > bool virtio_queue_enabled(VirtIODevice *vdev, int n); > hwaddr virtio_queue_get_avail_addr(VirtIODevice *vdev, int n); > hwaddr virtio_queue_get_used_addr(VirtIODevice *vdev, int n);