From patchwork Mon Jul 27 15:33:19 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Laurent Vivier X-Patchwork-Id: 1337046 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=cYb2bVpR; dkim-atps=neutral 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 ozlabs.org (Postfix) with ESMTPS id 4BFkNz6mJ2z9sVQ for ; Tue, 28 Jul 2020 01:33:54 +1000 (AEST) Received: from localhost ([::1]:33812 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1k058P-0005dX-R6 for incoming@patchwork.ozlabs.org; Mon, 27 Jul 2020 11:33:49 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:46652) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1k0587-0005cz-6J for qemu-devel@nongnu.org; Mon, 27 Jul 2020 11:33:31 -0400 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:58750 helo=us-smtp-delivery-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 1k0585-0003go-3f for qemu-devel@nongnu.org; Mon, 27 Jul 2020 11:33:30 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1595864008; 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; bh=tDjUQ2Z9JsNJEcx/9dZ18f+wBEDy9xDAp0GKz2Db+tE=; b=cYb2bVpReMb4eXa9oyHo9QKi6OcufT9YEFupH/9qru2clX/3vkb2lTh1Uf53chOOwp/vth d9UVCttdy2f9TeGccJaDPWoX7qYB4LqbqNC0Vc77Jxf9RAckBWRbabrZrTxMIxjuukOiUD s11xJsNvO8Ejm6JI275F13xp2oKkdsw= 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-321-dutLkrI7MLeqtvbK1FJ26Q-1; Mon, 27 Jul 2020 11:33:26 -0400 X-MC-Unique: dutLkrI7MLeqtvbK1FJ26Q-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 76A9B101C8AF for ; Mon, 27 Jul 2020 15:33:25 +0000 (UTC) Received: from thinkpad.redhat.com (ovpn-113-103.ams2.redhat.com [10.36.113.103]) by smtp.corp.redhat.com (Postfix) with ESMTP id B892B712C2; Mon, 27 Jul 2020 15:33:20 +0000 (UTC) From: Laurent Vivier To: qemu-devel@nongnu.org Subject: [PATCH] virtio-pci: fix virtio_pci_queue_enabled() Date: Mon, 27 Jul 2020 17:33:19 +0200 Message-Id: <20200727153319.43716-1-lvivier@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=207.211.31.81; envelope-from=lvivier@redhat.com; helo=us-smtp-delivery-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/07/27 03:37:14 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: Laurent Vivier , Jason Wang , Cindy Lu , "Michael S. Tsirkin" Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" 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 Reviewed-by: Richard Henderson Reviewed-by: Michael S. Tsirkin --- 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);