[bug report] drm/xe/svm: Implement prefetch support for SVM ranges

[Jason Gunthorpe]

On Mon, May 26, 2025 at 10:15:17PM +0530, Ghimiray, Himal Prasad wrote:
> 
> 
> On 26-05-2025 20:36, Dan Carpenter wrote:
> > Hello Himal Prasad Ghimiray,
> > 
> > Commit 09ba0a8f06cd ("drm/xe/svm: Implement prefetch support for SVM
> > ranges") from May 13, 2025 (linux-next), leads to the following
> > Smatch static checker warning:
> > 
> > 	drivers/gpu/drm/xe/xe_vm.c:2922 prefetch_ranges()
> > 	warn: passing positive error code 's32min-(-96),(-94)-(-15),(-13)-(-12),(-10)-(-2),1' to 'ERR_PTR'
> 
> Hi Dan,
> 
> Thanks for pointing this out. I see there's a gap in how hmm_range_fault()
> adheres to its documented behavior. I believe the function should sanitize
> positive return values from walk_page_range() to ensure consistency.
> 
> Jason can comment further on same.

Yeah, I don't think it should return positive error code, whatever is
doing that should be fixed. Can you send a patch?

Jason