Re: [PATCH v2] cxl: make cxl_bus_type constant

[Jonathan Cameron <Jonathan.Cameron@huawei.com>]

On Tue,  1 Jul 2025 14:07:39 +0200
Greg Kroah-Hartman <gregkh@linuxfoundation.org> wrote:

> Now that the driver core can properly handle constant struct bus_type,
> move the cxl_bus_type variable to be a constant structure as well,
> placing it into read-only memory which can not be modified at runtime.
> 
> Cc: Davidlohr Bueso <dave@stgolabs.net>
> Cc: Jonathan Cameron <jonathan.cameron@huawei.com>
> Cc: Dave Jiang <dave.jiang@intel.com>
> Cc: Alison Schofield <alison.schofield@intel.com>
> Cc: Vishal Verma <vishal.l.verma@intel.com>
> Cc: Ira Weiny <ira.weiny@intel.com>
> Cc: Dan Williams <dan.j.williams@intel.com>
> Cc: linux-cxl@vger.kernel.org
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>

> ---
> v2: fix up the subject line to be correct
> 
>  drivers/cxl/core/port.c | 2 +-
>  drivers/cxl/cxl.h       | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c
> index eb46c6764d20..0696f7fcef56 100644
> --- a/drivers/cxl/core/port.c
> +++ b/drivers/cxl/core/port.c
> @@ -2293,7 +2293,7 @@ static const struct attribute_group *cxl_bus_attribute_groups[] = {
>  	NULL,
>  };
>  
> -struct bus_type cxl_bus_type = {
> +const struct bus_type cxl_bus_type = {
>  	.name = "cxl",
>  	.uevent = cxl_bus_uevent,
>  	.match = cxl_bus_match,
> diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
> index 3f1695c96abc..e7b66ca1d423 100644
> --- a/drivers/cxl/cxl.h
> +++ b/drivers/cxl/cxl.h
> @@ -815,7 +815,7 @@ int cxl_dvsec_rr_decode(struct cxl_dev_state *cxlds,
>  
>  bool is_cxl_region(struct device *dev);
>  
> -extern struct bus_type cxl_bus_type;
> +extern const struct bus_type cxl_bus_type;
>  
>  struct cxl_driver {
>  	const char *name;