drm/radeon/kms: Only VM CS ioctl is supported on SI (v2)

v2: avoid double free.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/radeon/radeon_cs.c b/drivers/gpu/drm/radeon/radeon_cs.c
index 087bd50..5e459a3 100644
--- a/drivers/gpu/drm/radeon/radeon_cs.c
+++ b/drivers/gpu/drm/radeon/radeon_cs.c
@@ -253,6 +253,13 @@
 		return -EINVAL;
 	}
 
+	/* we only support VM on SI+ */
+	if ((p->rdev->family >= CHIP_TAHITI) &&
+	    ((p->cs_flags & RADEON_CS_USE_VM) == 0)) {
+		DRM_ERROR("VM required on SI+!\n");
+		return -EINVAL;
+	}
+
 	if (radeon_cs_get_ring(p, ring, priority))
 		return -EINVAL;