Re: [PATCH v2 2/7] x86/mce: add compat struct checking for XEN_MC_inject_v2

["Roger Pau Monné" <roger.pau@citrix.com>]

On Wed, Jul 01, 2020 at 12:25:48PM +0200, Jan Beulich wrote:
> 84e364f2eda2 ("x86: add CMCI software injection interface") merely made
> sure things would build, without any concern about things actually
> working:
> - despite the addition of xenctl_bitmap to xlat.lst, the resulting macro
>   wasn't invoked anywhere (which would have lead to recognizing that the
>   structure appeared to have no fully compatible layout, despite the use
>   of a 64-bit handle),
> - the interface struct itself was neither added to xlat.lst (and the
>   resulting macro then invoked) nor was any manual checking of
>   individual fields added.
> 
> Adjust compat header generation logic to retain XEN_GUEST_HANDLE_64(),
> which is intentionally layed out to be compatible between different size
> guests. Invoke the missing checking (implicitly through CHECK_mc).
> 
> No change in the resulting generated code.
> 
> Fixes: 84e364f2eda2 ("x86: add CMCI software injection interface")
> Signed-off-by: Jan Beulich <jbeulich@suse.com>

LGTM, just one question below.

> --- a/xen/tools/compat-build-header.py
> +++ b/xen/tools/compat-build-header.py
> @@ -19,6 +19,7 @@ pats = [
>   [ r"(^|[^\w])xen_?(\w*)_compat_t([^\w]|$$)", r"\1compat_\2_t\3" ],
>   [ r"(^|[^\w])XEN_?", r"\1COMPAT_" ],
>   [ r"(^|[^\w])Xen_?", r"\1Compat_" ],
> + [ r"(^|[^\w])COMPAT_HANDLE_64\(", r"\1XEN_GUEST_HANDLE_64(" ],

Why do you need to match with the opening parenthesis?

Is this for the #ifndef XEN_GUEST_HANDLE_64 instances? Don't they need
to also be replaced with the compat types?

Thanks, Roger.