Re: [PATCH v2 5/5] drm/panthor: Remove redundant panthor_fix_sparse_map_offset() call

[Steven Price <steven.price@arm.com>]

On 24/09/2026 12:04, Boris Brezillon wrote:
> op->remap.next->gem.offset is adjusted twice in
> panthor_gpuva_sm_step_remap() (once on the remap.next object, and once on
> the local map_op). Let's do it only once, and move this adjusment closer
> to the place it matters.
> 
> Reported-by: Akash Goel <akash.goel@arm.com>
> Closes: https://lore.kernel.org/dri-devel/b85679e3-5ca2-4d36-8675-2b968d97cb5b@arm.com/
> Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>

Reviewed-by: Steven Price <steven.price@arm.com>

> ---
>  drivers/gpu/drm/panthor/panthor_mmu.c | 12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/panthor/panthor_mmu.c b/drivers/gpu/drm/panthor/panthor_mmu.c
> index 01564d250adf..d8fb29ace5c4 100644
> --- a/drivers/gpu/drm/panthor/panthor_mmu.c
> +++ b/drivers/gpu/drm/panthor/panthor_mmu.c
> @@ -2397,11 +2397,6 @@ static int panthor_gpuva_sm_step_remap(struct drm_gpuva_op *op,
>  
>  	drm_gpuva_op_remap_to_unmap_range(&op->remap, &unmap_start, &unmap_range);
>  
> -	/* op->remap.prev's BO offset is always the same as the unmap va's, but
> -	 * that of op->remap.next must be adjusted so as to remain < SZ_2M
> -	 */
> -	panthor_fix_sparse_map_offset(op->remap.next, unmap_vma->flags);
> -
>  	if (!unmap_vma->evicted) {
>  		/*
>  		 * ARM IOMMU page table management code disallows partial unmaps of huge pages,
> @@ -2447,6 +2442,12 @@ static int panthor_gpuva_sm_step_remap(struct drm_gpuva_op *op,
>  		u64 addr = op->remap.next->va.addr;
>  		u64 size = unmap_start + unmap_range - op->remap.next->va.addr;
>  
> +		/* op->remap.prev's BO offset is always the same as the unmap
> +		 * va's, but that of op->remap.next must be adjusted so as to
> +		 * remain < SZ_2M
> +		 */
> +		panthor_fix_sparse_map_offset(op->remap.next, unmap_vma->flags);
> +
>  		if (!unmap_vma->evicted && size > 0) {
>  			struct drm_gpuva_op_map map_op = {
>  				.va.addr = addr,
> @@ -2454,7 +2455,6 @@ static int panthor_gpuva_sm_step_remap(struct drm_gpuva_op *op,
>  				.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);
>  			if (ret)
>