From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48718) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cTUzp-00034z-7k for qemu-devel@nongnu.org; Tue, 17 Jan 2017 09:44:26 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cTUzk-0002T4-C1 for qemu-devel@nongnu.org; Tue, 17 Jan 2017 09:44:25 -0500 Received: from mx1.redhat.com ([209.132.183.28]:51478) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cTUzk-0002Sr-5U for qemu-devel@nongnu.org; Tue, 17 Jan 2017 09:44:20 -0500 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 015AA21733 for ; Tue, 17 Jan 2017 14:44:20 +0000 (UTC) Date: Tue, 17 Jan 2017 16:44:19 +0200 From: "Michael S. Tsirkin" Message-ID: <20170117164326-mutt-send-email-mst@kernel.org> References: <1484625660-3312-1-git-send-email-jasowang@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1484625660-3312-1-git-send-email-jasowang@redhat.com> Subject: Re: [Qemu-devel] [PATCH] virtio: force VIRTIO_F_IOMMU_PLATFORM List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jason Wang Cc: qemu-devel@nongnu.org On Tue, Jan 17, 2017 at 12:01:00PM +0800, Jason Wang wrote: > We allow vhost to clear VIRITO_F_IOMMU_PLATFORM which is wrong since > VIRTIO_F_IOMMU_PLATFORM is mandatory for security. Fixing this by > enforce it after vdc->get_features(). > > Signed-off-by: Jason Wang > --- > hw/virtio/virtio-bus.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/hw/virtio/virtio-bus.c b/hw/virtio/virtio-bus.c > index d31cc00..a886011 100644 > --- a/hw/virtio/virtio-bus.c > +++ b/hw/virtio/virtio-bus.c > @@ -47,6 +47,7 @@ void virtio_bus_device_plugged(VirtIODevice *vdev, Error **errp) > VirtioBusState *bus = VIRTIO_BUS(qbus); > VirtioBusClass *klass = VIRTIO_BUS_GET_CLASS(bus); > VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev); > + bool has_iommu = virtio_host_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM); > > DPRINTF("%s: plug device.\n", qbus->name); > > @@ -63,8 +64,8 @@ void virtio_bus_device_plugged(VirtIODevice *vdev, Error **errp) > klass->device_plugged(qbus->parent, errp); > } > > - if (klass->get_dma_as != NULL && > - virtio_host_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM)) { > + if (klass->get_dma_as != NULL && has_iommu) { > + virtio_add_feature(&vdev->host_features, VIRTIO_F_IOMMU_PLATFORM); > vdev->dma_as = klass->get_dma_as(qbus->parent); > } else { > vdev->dma_as = &address_space_memory; I suspect that's not enough, we must also fail or disable vhost (depending on the options), otherwise things won't work. > -- > 2.7.4