virtio/vhost: minor fixes

This fixes two minor bugs: error handling in vhost,
 and capability processing in virtio.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull minor virtio/vhost fixes from Michael Tsirkin:
 "This fixes two minor bugs: error handling in vhost, and capability
  processing in virtio"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  vhost: fix error path in vhost_init_used()
  virtio-pci: read the right virtio_pci_notify_cap field

drivers/vhost/vhost.c

@@ -1156,6 +1156,8 @@ int vhost_init_used(struct vhost_virtqueue *vq)
 {
 	__virtio16 last_used_idx;
 	int r;
+	bool is_le = vq->is_le;
+
 	if (!vq->private_data) {
 		vq->is_le = virtio_legacy_is_little_endian();
 		return 0;
@@ -1165,15 +1167,20 @@ int vhost_init_used(struct vhost_virtqueue *vq)
 
 	r = vhost_update_used_flags(vq);
 	if (r)
-		return r;
+		goto err;
 	vq->signalled_used_valid = false;
-	if (!access_ok(VERIFY_READ, &vq->used->idx, sizeof vq->used->idx))
-		return -EFAULT;
+	if (!access_ok(VERIFY_READ, &vq->used->idx, sizeof vq->used->idx)) {
+		r = -EFAULT;
+		goto err;
+	}
 	r = __get_user(last_used_idx, &vq->used->idx);
 	if (r)
-		return r;
+		goto err;
 	vq->last_used_idx = vhost16_to_cpu(vq, last_used_idx);
 	return 0;
+err:
+	vq->is_le = is_le;
+	return r;
 }
 EXPORT_SYMBOL_GPL(vhost_init_used);
 

drivers/virtio/virtio_pci_modern.c

@@ -679,7 +679,7 @@ int virtio_pci_modern_probe(struct virtio_pci_device *vp_dev)
 
 	pci_read_config_dword(pci_dev,
 			      notify + offsetof(struct virtio_pci_notify_cap,
-						cap.length),
+						cap.offset),
 			      &notify_offset);
 
 	/* We don't know how many VQs we'll map, ahead of the time.