drm/nouveau: prevent oops if no mmu subdev present

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

diff --git a/drivers/gpu/drm/nouveau/nouveau_drm.c b/drivers/gpu/drm/nouveau/nouveau_drm.c
index 295e762..6164ea0 100644 (file)
--- a/drivers/gpu/drm/nouveau/nouveau_drm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_drm.c
@@ -430,6 +430,11 @@ nouveau_drm_load(struct drm_device *dev, unsigned long flags)
        nouveau_vga_init(drm);
 
        if (drm->device.info.family >= NV_DEVICE_INFO_V0_TESLA) {
+               if (!nvxx_device(&drm->device)->mmu) {
+                       ret = -ENOSYS;
+                       goto fail_device;
+               }
+
                ret = nvkm_vm_new(nvxx_device(&drm->device), 0, (1ULL << 40),
                                  0x1000, NULL, &drm->client.vm);
                if (ret)