drm/nvd0: lets not attempt to dereference a nv50_display pointer

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

1 files changed, 8 insertions, 4 deletions

diff --git a/drivers/gpu/drm/nouveau/nouveau_object.c b/drivers/gpu/drm/nouveau/nouveau_object.c
index 4406c1751069..02222c540aee 100644
--- a/drivers/gpu/drm/nouveau/nouveau_object.c
+++ b/drivers/gpu/drm/nouveau/nouveau_object.c
@@ -693,6 +693,7 @@ nouveau_gpuobj_channel_init_pramin(struct nouveau_channel *chan)
 static int
 nvc0_gpuobj_channel_init(struct nouveau_channel *chan, struct nouveau_vm *vm)
 {
+        struct drm_nouveau_private *dev_priv = chan->dev->dev_private;
         struct drm_device *dev = chan->dev;
         struct nouveau_gpuobj *pgd = NULL;
         struct nouveau_vm_pgd *vpgd;
@@ -722,6 +723,9 @@ nvc0_gpuobj_channel_init(struct nouveau_channel *chan, struct nouveau_vm *vm)
         nv_wo32(chan->ramin, 0x020c, 0x000000ff);
 
         /* map display semaphore buffers into channel's vm */
+        if (dev_priv->card_type >= NV_D0)
+                return 0;
+
         for (i = 0; i < 2; i++) {
                 struct nv50_display_crtc *dispc = &nv50_display(dev)->crtc[i];
 
@@ -875,18 +879,18 @@ nouveau_gpuobj_channel_takedown(struct nouveau_channel *chan)
 
         NV_DEBUG(dev, "ch%d\n", chan->id);
 
-        if (dev_priv->card_type >= NV_50) {
+        if (dev_priv->card_type >= NV_50 && dev_priv->card_type <= NV_C0) {
                 struct nv50_display *disp = nv50_display(dev);
 
                 for (i = 0; i < dev->mode_config.num_crtc; i++) {
                         struct nv50_display_crtc *dispc = &disp->crtc[i];
                         nouveau_bo_vma_del(dispc->sem.bo, &chan->dispc_vma[i]);
                 }
-
-                nouveau_vm_ref(NULL, &chan->vm, chan->vm_pd);
-                nouveau_gpuobj_ref(NULL, &chan->vm_pd);
         }
 
+        nouveau_vm_ref(NULL, &chan->vm, chan->vm_pd);
+        nouveau_gpuobj_ref(NULL, &chan->vm_pd);
+
         if (drm_mm_initialized(&chan->ramin_heap))
                 drm_mm_takedown(&chan->ramin_heap);
         nouveau_gpuobj_ref(NULL, &chan->ramin);