[PATCH 3/4] drm/xe: Allow freeing of a managed bo

[Michal Wajdeczko]

On 7/25/2025 2:21 AM, John.C.Harrison at Intel.com wrote:
> From: John Harrison <John.C.Harrison at Intel.com>
> 
> If a bo is created via xe_managed_bo_create_pin_map() then it cannot be
> freed by the driver using xe_bo_unpin_map_no_vm(), or indeed any other
> existing function. The DRM layer will still have a pointer stashed
> away for later freeing, causing a invalid memory access on driver
> unload. So add a helper for releasing the DRM action as well.
> 
> Signed-off-by: John Harrison <John.C.Harrison at Intel.com>
> ---
>  drivers/gpu/drm/xe/xe_bo.c | 5 +++++
>  drivers/gpu/drm/xe/xe_bo.h | 1 +
>  2 files changed, 6 insertions(+)
> 
> diff --git a/drivers/gpu/drm/xe/xe_bo.c b/drivers/gpu/drm/xe/xe_bo.c
> index ffca1cea5585..472cadcfc4dd 100644
> --- a/drivers/gpu/drm/xe/xe_bo.c
> +++ b/drivers/gpu/drm/xe/xe_bo.c
> @@ -2222,6 +2222,11 @@ struct xe_bo *xe_managed_bo_create_pin_map(struct xe_device *xe, struct xe_tile
>  	return bo;
>  }
>  

please add kernel-doc for this new public function

> +void xe_managed_bo_unpin_map_no_vm(struct xe_device *xe, struct xe_bo *bo)

do we really need xe? we can get xe from xe_bo_device(bo) if needed

> +{
> +	devm_release_action(xe->drm.dev, __xe_bo_unpin_map_no_vm, bo);
> +}do we want to use this function right away in xe_managed_bo_reinit_in_vram() ?

> +
>  struct xe_bo *xe_managed_bo_create_from_data(struct xe_device *xe, struct xe_tile *tile,
>  					     const void *data, size_t size, u32 flags)
>  {
> diff --git a/drivers/gpu/drm/xe/xe_bo.h b/drivers/gpu/drm/xe/xe_bo.h
> index 8cce413b5235..72f4348d0d52 100644
> --- a/drivers/gpu/drm/xe/xe_bo.h
> +++ b/drivers/gpu/drm/xe/xe_bo.h
> @@ -122,6 +122,7 @@ struct xe_bo *xe_bo_create_pin_map_at_aligned(struct xe_device *xe,
>  					      u64 alignment);
>  struct xe_bo *xe_managed_bo_create_pin_map(struct xe_device *xe, struct xe_tile *tile,
>  					   size_t size, u32 flags);
> +void xe_managed_bo_unpin_map_no_vm(struct xe_device *xe, struct xe_bo *bo);
>  struct xe_bo *xe_managed_bo_create_from_data(struct xe_device *xe, struct xe_tile *tile,
>  					     const void *data, size_t size, u32 flags);
>  int xe_managed_bo_reinit_in_vram(struct xe_device *xe, struct xe_tile *tile, struct xe_bo **src);