Re: [PATCH 3/4] cxl/mbox: Add variable output size validation for internal commands

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

On Mon, 05 Dec 2022 20:22:39 -0800
Dan Williams <dan.j.williams@intel.com> wrote:

> cxl_internal_send_cmd() skips output size validation for variable output
> commands which is not ideal. Most of the time internal usages want to
> fail if the output size does not match what was requested. For other
> commands where the caller cannot predict the size there is usually a
> a header that conveys how much vaild data is in the payload. For those
> cases add @min_out as a parameter to specify what the minimum response
> payload needs to be for the caller to parse the rest of the payload.
> 
> In this patch only Get Supported Logs has that behavior, but going
> forward records retrieval commands like Get Poison List and Get Event
> Records can use @min_out to retrieve a variable amount of records.
> 
> Critically, this validation scheme skips the needs to interrogate the
> cxl_mem_commands array which in turn frees up the implementation to
> support internal command enabling without also enabling external / user
> commands.
> 
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Makes sense.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>