Linux Virtualization - Nov 2016 - [PATCH 1/2] vhost: remove unused feature bit

Signed-off-by: Jason Wang <jasowang at redhat.com>
---
 include/uapi/linux/vhost.h | 2 --
 1 file changed, 2 deletions(-)

diff --git a/include/uapi/linux/vhost.h b/include/uapi/linux/vhost.h
index 56b7ab5..60180c0 100644
--- a/include/uapi/linux/vhost.h
+++ b/include/uapi/linux/vhost.h
@@ -172,8 +172,6 @@ struct vhost_memory {
 #define VHOST_F_LOG_ALL 26
 /* vhost-net should add virtio_net_hdr for RX, and strip for TX packets. */
 #define VHOST_NET_F_VIRTIO_NET_HDR 27
-/* Vhost have device IOTLB */
-#define VHOST_F_DEVICE_IOTLB 63
 
 /* VHOST_SCSI specific definitions */
 
-- 
2.7.4

When IOTLB is not enabled, we should forbid IOTLB invalidation to
avoid a NULL pointer dereference.

Signed-off-by: Jason Wang <jasowang at redhat.com>
---
 drivers/vhost/vhost.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index c6f2d89..7d338d5 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -959,6 +959,10 @@ int vhost_process_iotlb_msg(struct vhost_dev *dev,
 		vhost_iotlb_notify_vq(dev, msg);
 		break;
 	case VHOST_IOTLB_INVALIDATE:
+		if (!dev->iotlb) {
+			ret = -EFAULT;
+			break;
+		}
 		vhost_del_umem_range(dev->iotlb, msg->iova,
 				     msg->iova + msg->size - 1);
 		break;
-- 
2.7.4