virtio: don't require a config space on the console device.

Strictly, it's only needed when we have features (size or multiport).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

1 files changed, 4 insertions, 1 deletions

diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index 26afb56a8073..fae2dbbf5745 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -1986,7 +1986,10 @@ static int virtcons_probe(struct virtio_device *vdev)
         bool multiport;
         bool early = early_put_chars != NULL;
 
-        if (!vdev->config->get) {
+        /* We only need a config space if features are offered */
+        if (!vdev->config->get &&
+            (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_SIZE)
+             || virtio_has_feature(vdev, VIRTIO_CONSOLE_F_MULTIPORT))) {
                 dev_err(&vdev->dev, "%s failure: config access disabled\n",
                         __func__);
                 return -EINVAL;