drm/nouveau: fix crash with noaccel=1

Reported-by: Ortwin Glück <odi@odi.ch>
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/drivers/gpu/drm/nouveau/nouveau_abi16.c b/drivers/gpu/drm/nouveau/nouveau_abi16.c
index cc79c796afee..cbf1fc60a386 100644
--- a/drivers/gpu/drm/nouveau/nouveau_abi16.c
+++ b/drivers/gpu/drm/nouveau/nouveau_abi16.c
@@ -241,6 +241,10 @@ nouveau_abi16_ioctl_channel_alloc(ABI16_IOCTL_ARGS)
 
         if (unlikely(!abi16))
                 return -ENOMEM;
+
+        if (!drm->channel)
+                return nouveau_abi16_put(abi16, -ENODEV);
+
         client = nv_client(abi16->client);
 
         if (init->fb_ctxdma_handle == ~0 || init->tt_ctxdma_handle == ~0)