Re: [PATCH v4 5/5] drm/xe/vm: Skip ufence association for CPU address mirror VMA during MAP

[Matthew Brost <matthew.brost@intel.com>]

On Mon, Nov 03, 2025 at 11:39:57AM +0530, Himal Prasad Ghimiray wrote:
> The MAP operation for a CPU address mirror VMA does not require ufence
> association because such mappings are not GPU-synchronized and do not
> participate in GPU job completion signaling.
> 
> Remove the unnecessary ufence addition for this case to avoid -EBUSY
> failure in check_ufence of unbind ops.
> 
> Cc: Matthew Brost <matthew.brost@intel.com>

Reviewed-by: Matthew Brost <matthew.brost@intel.com>

> Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
> Signed-off-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
> ---
>  drivers/gpu/drm/xe/xe_vm.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c
> index 12354e03c3e2..79c7383bf247 100644
> --- a/drivers/gpu/drm/xe/xe_vm.c
> +++ b/drivers/gpu/drm/xe/xe_vm.c
> @@ -3202,7 +3202,8 @@ static void op_add_ufence(struct xe_vm *vm, struct xe_vma_op *op,
>  {
>  	switch (op->base.op) {
>  	case DRM_GPUVA_OP_MAP:
> -		vma_add_ufence(op->map.vma, ufence);
> +		if (!xe_vma_is_cpu_addr_mirror(op->map.vma))
> +			vma_add_ufence(op->map.vma, ufence);
>  		break;
>  	case DRM_GPUVA_OP_REMAP:
>  		if (op->remap.prev)
> -- 
> 2.34.1
>