Re: [bug report] drm/xe/psmi: Add debugfs interface for PSMI

[Dan Carpenter <dan.carpenter@linaro.org>]

On Mon, Sep 22, 2025 at 03:52:40PM -0500, Lucas De Marchi wrote:
> On Tue, Aug 26, 2025 at 10:51:02AM +0300, Dan Carpenter wrote:
> > Hello Lucas De Marchi,
> > 
> > Commit aaa0c1f50a3d ("drm/xe/psmi: Add debugfs interface for PSMI")
> > from Aug 21, 2025 (linux-next), leads to the following Smatch static
> > checker warning:
> > 
> > 	drivers/gpu/drm/xe/xe_psmi.c:93 psmi_alloc_object()
> > 	error: 'bo' dereferencing possible ERR_PTR()
> > 
> > drivers/gpu/drm/xe/xe_psmi.c
> >    68 static struct xe_bo *psmi_alloc_object(struct xe_device *xe,
> >    69                                        unsigned int id, size_t bo_size)
> >    70 {
> >    71         struct xe_bo *bo = NULL;
> >    72         struct xe_tile *tile;
> >    73         int err;
> >    74
> >    75         if (!id || !bo_size)
> >    76                 return NULL;
> > 
> > I really encourage everyone to document why functions return both error
> > pointers and NULL.  Here "bo_size" can never actually be zero so that's
> > an impossible path.  Presumably id can be zero, but what's the point of
> > storing a NULL in xe->psmi.capture_obj[0]?  It feels like it complicates
> > things...
> 
> neither id nor bo_size can be 0 at this point. We could simply remove
> the check or replace by
> 
> 	xe_assert(xe, id);
> 	xe_assert(xe, bo_size);

That works, or you could return an error pointer.  That would also be fine.

regards,
dan carpenter