From: Michael S. Tsirkin <mst@redhat.com>
Date: Mon, 12 Jan 2015 14:23:37 +0000 (+0200)
Subject: virtio/scsi: verify device has config space
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=8cab3cd6ad622f070b18cd1c2e3b97e1d3806629;p=linux-beck.git

virtio/scsi: verify device has config space

Some devices might not implement config space access
(e.g. remoteproc used not to - before 3.9).
virtio/scsi needs config space access so make it
fail gracefully if not there.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
---

diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
index c52bb5dfaedb..f164f24a4a55 100644
--- a/drivers/scsi/virtio_scsi.c
+++ b/drivers/scsi/virtio_scsi.c
@@ -950,6 +950,12 @@ static int virtscsi_probe(struct virtio_device *vdev)
 	u32 num_queues;
 	struct scsi_host_template *hostt;
 
+	if (!vdev->config->get) {
+		dev_err(&vdev->dev, "%s failure: config access disabled\n",
+			__func__);
+		return -EINVAL;
+	}
+
 	/* We need to know how many queues before we allocate. */
 	num_queues = virtscsi_config_get(vdev, num_queues) ? : 1;