Re: [PATCH 1/2] drm/xe/svm: Ensure data will be migrated to system if indicated by madvise.

["Ghimiray, Himal Prasad" <himal.prasad.ghimiray@intel.com>]

On 08-10-2025 16:40, Thomas Hellström wrote:
> If the location madvise() is set to
> DRM_XE_PREFERRED_LOC_DEFAULT_SYSTEM, the drm_pagemap in the
> SVM gpu fault handler will be set to NULL. However there is nothing
> that explicitly migrates the data to system if it is already present
> in device memory.
> 
> In that case, set the device memory owner to NULL to ensure
> data gets properly migrated to system on page-fault.
> 
> Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
> ---
>   drivers/gpu/drm/xe/xe_svm.c | 3 +++
>   1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/gpu/drm/xe/xe_svm.c b/drivers/gpu/drm/xe/xe_svm.c
> index 7e2db71ff34e..fd906eb03d71 100644
> --- a/drivers/gpu/drm/xe/xe_svm.c
> +++ b/drivers/gpu/drm/xe/xe_svm.c
> @@ -1034,6 +1034,9 @@ static int __xe_svm_handle_pagefault(struct xe_vm *vm, struct xe_vma *vma,
>   	if (err)
>   		return err;
>   
> +	dpagemap = xe_vma_resolve_pagemap(vma, tile);
> +	if (!dpagemap && !ctx.devmem_only)
> +		ctx.device_private_page_owner = NULL;
>   	range = xe_svm_range_find_or_insert(vm, fault_addr, vma, &ctx);


remove redundant dpagemap assignment before 
xe_svm_range_needs_migrate_to_vram check.

  >
>   	if (IS_ERR(range))