Re: [PATCH] drm/panthor: Fix NPD issue on partial unmap of an evicted BO

[Adrián Larumbe]

On 2026-06-23 13:41:12+01:00, Akash Goel wrote:
> On 6/23/26 13:09, Boris Brezillon wrote:
> 
> > On Tue, 23 Jun 2026 12:17:51 +0100
> > Akash Goel <akash.goel@xxxxxxx> wrote:
> > 
> > 
> > Nah, you're correct, the patching of the drm_gpuva is independent of the
> > adjusted unmap range, so we should be good even if we don't adjust this
> > range for evicted sparse mappings. Sorry for the noise.
> 
> No worries. Thanks for confirming.
> 
> Since I had a closer look at the code, sorry I have another doubt.
> 
> Do we really need the call to 'panthor_fix_sparse_map_offset()' in the 
> following code block ?. The 'op->remap.next->gem.offset' would already 
> have been patched before.

You're right, it's completely unnecessary. Maybe replace it with a comment that says
the right offset had already been adjusted earlier in the function?

Other than that:

Reviewed-by: Adrián Larumbe <adrian.larumbe@xxxxxxxxxxxxx>

> 
> 	if (op->remap.next) {
> 		u64 addr = op->remap.next->va.addr;
> 		u64 size = unmap_start + unmap_range - op->remap.next->va.addr;
> 
> 		if (!unmap_vma->evicted && size > 0) {
> 			struct drm_gpuva_op_map map_op = {
> 				.va.addr = addr,
> 				.va.range = size,
> 				.gem.obj = op->remap.next->gem.obj,
> 				.gem.offset = op->remap.next->gem.offset,
> 			};
> 			panthor_fix_sparse_map_offset(&map_op, unmap_vma->flags);
> 
> 			ret = panthor_vm_exec_map_op(vm, unmap_vma->flags, &map_op);
> 
> > Reviewed-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxx>
> 
> Sorry I realized that indentation needs to be fixed in my patch.
> 
> Will send a v2 and ad your r-b tag.
> 
> Best regards
> Akash