drm/nouveau: fix oopses caused by clear being called on unpopulated ttms

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

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/gpu/drm/nouveau/nouveau_sgdma.c b/drivers/gpu/drm/nouveau/nouveau_sgdma.c
index b75258a9fe44..c8a463b76c89 100644
--- a/drivers/gpu/drm/nouveau/nouveau_sgdma.c
+++ b/drivers/gpu/drm/nouveau/nouveau_sgdma.c
@@ -67,7 +67,10 @@ nouveau_sgdma_clear(struct ttm_backend *be)
                         pci_unmap_page(dev->pdev, nvbe->pages[nvbe->nr_pages],
                                        PAGE_SIZE, PCI_DMA_BIDIRECTIONAL);
                 }
+                nvbe->unmap_pages = false;
         }
+
+        nvbe->pages = NULL;
 }
 
 static void