Re: [PATCH] drm/nouveau/gsp: Fix possible NULL pointer dereference warning in r535_dmac_alloc

[Timur Tabi]

On Sat, 2026-04-18 at 14:12 +0200, Danilo Krummrich wrote:
> Are we sure that this can ever return NULL in the first place? I know that
> nvkm_gsp_rm_alloc_get() internally checks for IS_ERR_OR_NULL(), but I couldn't
> find anything within the callchain that would actually return NULL.
> 
> That said, I think IS_ERR_OR_NULL() checks are misleading.

I posted a patch a couple months ago that cleans up an IS_ERR check, but it was never picked up:

https://lore.freedesktop.org/nouveau/20260103000756.1002890-1-ttabi@xxxxxxxxxx/T/#u

I'm quite certain that there are other similar issues in Nouveau w.r.t. IS_ERR_OR_NULL.

I think an audit of the Nouveau error paths is in order.  I suspect that Ben's big refactors
over the past year have resulted in some invalid error paths.