vhost: silence an unused-variable warning

On some architectures, the MMU can be disabled, leading to access_ok()
becoming an empty macro that does not evaluate its size argument,
which in turn produces an unused-variable warning:

drivers/vhost/vhost.c:1191:9: error: unused variable 's' [-Werror,-Wunused-variable]
        size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;

Mark the variable as __maybe_unused to shut up that warning.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Arnd Bergmann 2019-03-06 12:05:49 +01:00 committed by Michael S. Tsirkin
parent ab7a2375fb
commit cfdbb4ed31

View File

@ -1188,7 +1188,7 @@ static bool vq_access_ok(struct vhost_virtqueue *vq, unsigned int num,
struct vring_used __user *used)
{
size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
size_t s __maybe_unused = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
return access_ok(desc, num * sizeof *desc) &&
access_ok(avail,