Re: [PATCH v25 08/11] cxl: Export function for unwinding cxl by accelerators

[Dan Williams <dan.j.williams@intel.com>]

alejandro.lucero-palau@ wrote:
> From: Alejandro Lucero <alucerop@amd.com>
> 
> Add cxl_unregister_region() to the accelerator driver API
> for a clean exit.
> 
> Signed-off-by: Alejandro Lucero <alucerop@amd.com>
> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> ---
>  drivers/cxl/core/region.c | 8 ++++++++
>  include/cxl/cxl.h         | 1 +
>  2 files changed, 9 insertions(+)
> 
> diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
> index 9c3ba911d865..b3a6d08be461 100644
> --- a/drivers/cxl/core/region.c
> +++ b/drivers/cxl/core/region.c
> @@ -2490,6 +2490,14 @@ static void unregister_region(void *_cxlr)
>  	put_device(&cxlr->dev);
>  }
>  
> +void cxl_unregister_region(struct cxl_region *cxlr)
> +{
> +	struct cxl_port *port = to_cxl_port(cxlr->cxlrd->cxlsd.cxld.dev.parent);
> +
> +	devm_release_action(port->uport_dev, unregister_region, cxlr);
> +}
> +EXPORT_SYMBOL_NS_GPL(cxl_unregister_region, "CXL");

devm_release_action() must only run from port->uport_dev attach context,
I.e. a context known to not race ->remove() / devres_release_all().