From: Ben Skeggs bskeggs@redhat.com
[ Upstream commit 0e6176c6d286316e9431b4f695940cfac4ffe6c2 ]
The implementations for most channel types contains a map of methods to priv registers in order to provide debugging info when a disp exception has been raised.
This info is missing from the implementation of PIO channels as they're rather simplistic already, however, if an exception is raised by one of them, we'd end up triggering a NULL-pointer deref. Not ideal...
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=206299 Signed-off-by: Ben Skeggs bskeggs@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- drivers/gpu/drm/nouveau/nvkm/engine/disp/channv50.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/disp/channv50.c b/drivers/gpu/drm/nouveau/nvkm/engine/disp/channv50.c index bcf32d9..50e3539 100644 --- a/drivers/gpu/drm/nouveau/nvkm/engine/disp/channv50.c +++ b/drivers/gpu/drm/nouveau/nvkm/engine/disp/channv50.c @@ -74,6 +74,8 @@
if (debug > subdev->debug) return; + if (!mthd) + return;
for (i = 0; (list = mthd->data[i].mthd) != NULL; i++) { u32 base = chan->head * mthd->addr;