Re: [PATCH 3/3] cxl/uapi: Add warning on CXL command enum

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

On Tue, 27 Dec 2022 06:52:11 -0800
Ira Weiny <ira.weiny@intel.com> wrote:

> The CXL command enum is exported to user space and must maintain
> backwards compatibility.
> 
> Add comment that new defines must be added to the end of the list.
> 
> Suggested-by: Dan Williams <dan.j.williams@intel.com>
> Signed-off-by: Ira Weiny <ira.weiny@intel.com>

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

> ---
>  include/uapi/linux/cxl_mem.h | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/include/uapi/linux/cxl_mem.h b/include/uapi/linux/cxl_mem.h
> index 555f9140e2bc..b3fd46af70f8 100644
> --- a/include/uapi/linux/cxl_mem.h
> +++ b/include/uapi/linux/cxl_mem.h
> @@ -19,6 +19,10 @@
>  #define CXL_MEM_QUERY_COMMANDS _IOR(0xCE, 1, struct cxl_mem_query_commands)
>  #define CXL_MEM_SEND_COMMAND _IOWR(0xCE, 2, struct cxl_send_command)
>  
> +/*
> + * NOTE: New defines must be added to the end of the list to preserve
> + * compatibility because this enum is exported to user space.
> + */
>  #define CXL_CMDS                                                          \
>  	___C(INVALID, "Invalid Command"),                                 \
>  	___C(IDENTIFY, "Identify Command"),                               \
>