From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51357) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bQHDD-0007JR-RE for qemu-devel@nongnu.org; Thu, 21 Jul 2016 12:52:41 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bQHD9-00059j-Q4 for qemu-devel@nongnu.org; Thu, 21 Jul 2016 12:52:39 -0400 Received: from mail-lf0-x242.google.com ([2a00:1450:4010:c07::242]:33940) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bQHD9-00059d-HV for qemu-devel@nongnu.org; Thu, 21 Jul 2016 12:52:35 -0400 Received: by mail-lf0-x242.google.com with SMTP id l69so5928588lfg.1 for ; Thu, 21 Jul 2016 09:52:35 -0700 (PDT) Reply-To: marcel@redhat.com References: <146911619705.23920.6002060635853247073.stgit@bahia.lan> From: Marcel Apfelbaum Message-ID: <5790FDCC.2010509@gmail.com> Date: Thu, 21 Jul 2016 19:52:28 +0300 MIME-Version: 1.0 In-Reply-To: <146911619705.23920.6002060635853247073.stgit@bahia.lan> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v2] virtio-pci: error out when both legacy and modern modes are disabled List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Greg Kurz , "Michael S. Tsirkin" Cc: Cornelia Huck , qemu-devel@nongnu.org On 07/21/2016 06:52 PM, Greg Kurz wrote: > From: Greg Kurz > > Without presuming if we got there because of a user mistake or some > more subtle bug in the tooling, it really does not make sense to > implement a non-functional device. > > Signed-off-by: Greg Kurz > Signed-off-by: Greg Kurz > --- > v2: - error out at realize time as suggested by Connie > - updated title and changelog > --- > hw/virtio/virtio-pci.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c > index f0677b73d860..8d707aac0c21 100644 > --- a/hw/virtio/virtio-pci.c > +++ b/hw/virtio/virtio-pci.c > @@ -1838,6 +1838,12 @@ static void virtio_pci_dc_realize(DeviceState *qdev, Error **errp) > VirtIOPCIProxy *proxy = VIRTIO_PCI(qdev); > PCIDevice *pci_dev = &proxy->pci_dev; > > + if (proxy->flags & VIRTIO_PCI_FLAG_DISABLE_LEGACY && > + proxy->flags & VIRTIO_PCI_FLAG_DISABLE_MODERN) { > + error_setg(errp, "device is unserviceable when both legacy and modern modes are disabled. At least one of the disable-modern or disable-legacy properties should be set to false."); > + return; > + } > + Hi Greg, I agree with the patch, but other patch in the mailing list replaces the flags with standalone fields: https://lists.gnu.org/archive/html/qemu-devel/2016-07/msg04744.html Also the error line may be too long and need to be truncated. Thanks, Marcel > if (!(proxy->flags & VIRTIO_PCI_FLAG_DISABLE_PCIE) && > !(proxy->flags & VIRTIO_PCI_FLAG_DISABLE_MODERN)) { > pci_dev->cap_present |= QEMU_PCI_CAP_EXPRESS; > >