From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:44266) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZHpri-0004BE-KK for qemu-devel@nongnu.org; Wed, 22 Jul 2015 04:59:03 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZHprX-0000Oo-Qs for qemu-devel@nongnu.org; Wed, 22 Jul 2015 04:59:02 -0400 Received: from e06smtp14.uk.ibm.com ([195.75.94.110]:36355) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZHprX-0000Ny-Ib for qemu-devel@nongnu.org; Wed, 22 Jul 2015 04:58:51 -0400 Received: from /spool/local by e06smtp14.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 22 Jul 2015 09:58:48 +0100 Received: from b06cxnps4075.portsmouth.uk.ibm.com (d06relay12.portsmouth.uk.ibm.com [9.149.109.197]) by d06dlp03.portsmouth.uk.ibm.com (Postfix) with ESMTP id 4B7311B08070 for ; Wed, 22 Jul 2015 10:00:02 +0100 (BST) Received: from d06av01.portsmouth.uk.ibm.com (d06av01.portsmouth.uk.ibm.com [9.149.37.212]) by b06cxnps4075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id t6M8wjwN27852860 for ; Wed, 22 Jul 2015 08:58:45 GMT Received: from d06av01.portsmouth.uk.ibm.com (localhost [127.0.0.1]) by d06av01.portsmouth.uk.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id t6M8wjUe003085 for ; Wed, 22 Jul 2015 02:58:45 -0600 Date: Wed, 22 Jul 2015 10:58:43 +0200 From: Cornelia Huck Message-ID: <20150722105843.41d22942.cornelia.huck@de.ibm.com> In-Reply-To: <1437544792-3949-3-git-send-email-jasowang@redhat.com> References: <1437544792-3949-1-git-send-email-jasowang@redhat.com> <1437544792-3949-3-git-send-email-jasowang@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH V3 2/3] virtio-blk: fail get_features when both scsi and 1.0 were set List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jason Wang Cc: pbonzini@redhat.com, qemu-devel@nongnu.org, mst@redhat.com On Wed, 22 Jul 2015 13:59:51 +0800 Jason Wang wrote: > SCSI passthrough was no longer supported in virtio 1.0, so this patch > fail the get_features() when both 1.0 and scsi is set. And also only > advertise VIRTIO_BLK_F_SCSI for legacy virtio-blk device. > > Signed-off-by: Jason Wang > --- > hw/block/virtio-blk.c | 9 ++++++++- > 1 file changed, 8 insertions(+), 1 deletion(-) > > diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c > index 4c27974..4716c3e 100644 > --- a/hw/block/virtio-blk.c > +++ b/hw/block/virtio-blk.c > @@ -731,7 +731,14 @@ static uint64_t virtio_blk_get_features(VirtIODevice *vdev, uint64_t features, > virtio_add_feature(&features, VIRTIO_BLK_F_GEOMETRY); > virtio_add_feature(&features, VIRTIO_BLK_F_TOPOLOGY); > virtio_add_feature(&features, VIRTIO_BLK_F_BLK_SIZE); > - virtio_add_feature(&features, VIRTIO_BLK_F_SCSI); > + if (__virtio_has_feature(features, VIRTIO_F_VERSION_1)) { > + if (s->conf.scsi) { > + error_setg(errp, "Virtio 1.0 does not support scsi passthrough!"); > + return 0; > + } > + } else { > + virtio_add_feature(&features, VIRTIO_BLK_F_SCSI); > + } > > if (s->conf.config_wce) { > virtio_add_feature(&features, VIRTIO_BLK_F_CONFIG_WCE); Do we advertise F_SCSI even if scsi is not configured in order to keep the same bits as before? I'm afraid I don't remember, that thread was long :/ I'm asking because I'd like to depend on that bit to decide whether I can negotiate revision 1 for ccw and subsequently offer VERSION_1. It would be an easy thing to do, and I'd like to avoid mucking around with device-specific configuration from the transport. To illustrate what I'm talking about, my current patchset for virtio-1 on ccw is here: git://github.com/cohuck/qemu virtio-1-ccw-2.5