From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=51603 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PKz59-0002Sv-3L for qemu-devel@nongnu.org; Tue, 23 Nov 2010 15:03:36 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1PKz4o-0007lQ-P2 for qemu-devel@nongnu.org; Tue, 23 Nov 2010 15:03:14 -0500 Received: from mx1.redhat.com ([209.132.183.28]:46314) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1PKz4o-0007lD-9X for qemu-devel@nongnu.org; Tue, 23 Nov 2010 15:02:54 -0500 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id oANK2rO5028055 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Tue, 23 Nov 2010 15:02:53 -0500 Date: Tue, 23 Nov 2010 22:02:40 +0200 From: "Michael S. Tsirkin" Message-ID: <20101123200240.GA4436@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Subject: [Qemu-devel] [PATCH] virtio: fix up VQ checks List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org, Juan Quintela When migration triggers before a VQ is initialized, base pa is 0 and last_used_index must be 0 too: we don't have a ring to compare to. This fixes a bug introduced in 258dc7c96bb4b7ca71d5bee811e73933310e168c. Reporrted-by: Juan Quintela Signed-off-by: Michael S. Tsirkin --- Compile-tested only. Juan, could you tell me whether this fixes the bug you see please? hw/virtio.c | 23 ++++++++++++++--------- 1 files changed, 14 insertions(+), 9 deletions(-) diff --git a/hw/virtio.c b/hw/virtio.c index a2a657e..1df3578 100644 --- a/hw/virtio.c +++ b/hw/virtio.c @@ -681,7 +681,6 @@ int virtio_load(VirtIODevice *vdev, QEMUFile *f) uint32_t features; uint32_t supported_features = vdev->binding->get_features(vdev->binding_opaque); - uint16_t num_heads; if (vdev->binding->load_config) { ret = vdev->binding->load_config(vdev->binding_opaque, f); @@ -712,17 +711,23 @@ int virtio_load(VirtIODevice *vdev, QEMUFile *f) qemu_get_be16s(f, &vdev->vq[i].last_avail_idx); if (vdev->vq[i].pa) { + uint16_t nheads; virtqueue_init(&vdev->vq[i]); - } - num_heads = vring_avail_idx(&vdev->vq[i]) - vdev->vq[i].last_avail_idx; - /* Check it isn't doing very strange things with descriptor numbers. */ - if (num_heads > vdev->vq[i].vring.num) { - fprintf(stderr, "VQ %d size 0x%x Guest index 0x%x " + nheads = vring_avail_idx(&vdev->vq[i]) - vdev->vq[i].last_avail_idx; + /* Check it isn't doing very strange things with descriptor numbers. */ + if (nheads > vdev->vq[i].vring.num) { + fprintf(stderr, "VQ %d size 0x%x Guest index 0x%x " "inconsistent with Host index 0x%x: delta 0x%x\n", - i, vdev->vq[i].vring.num, + i, vdev->vq[i].vring.num, vring_avail_idx(&vdev->vq[i]), - vdev->vq[i].last_avail_idx, num_heads); - return -1; + vdev->vq[i].last_avail_idx, nheads); + return -1; + } + } else if (vdev->vq[i].last_avail_idx) { + fprintf(stderr, "VQ %d address 0x0 " + "inconsistent with Host index 0x%x\n", + i, vdev->vq[i].last_avail_idx); + return -1; } if (vdev->binding->load_queue) { ret = vdev->binding->load_queue(vdev->binding_opaque, i, f); -- 1.7.3.2.91.g446ac