Re: [PATCH v7 08/12] xen: add /buildinfo/config entry to hypervisor filesystem

[Jan Beulich <jbeulich@xxxxxxxx>]

On 02.04.2020 17:46, Juergen Gross wrote:
> --- a/xen/common/Kconfig
> +++ b/xen/common/Kconfig
> @@ -353,6 +353,16 @@ config DOM0_MEM
>  
>         Leave empty if you are not sure what to specify.
>  
> +config HYPFS_CONFIG
> +     bool "Provide hypervisor .config via hypfs entry"
> +     default y

My initial reaction was to ask for "depends on HYPFS", but then
I noticed the earlier patch doesn't introduce such. Am I
mis-remembering that it was agreed to make the whole thing
possible to disable at least in EXPERT mode?

> --- a/xen/common/kernel.c
> +++ b/xen/common/kernel.c
> @@ -389,6 +389,16 @@ static HYPFS_STRING_INIT(compile_date, "compile_date");
>  static HYPFS_STRING_INIT(compile_domain, "compile_domain");
>  static HYPFS_STRING_INIT(extra, "extra");
>  
> +#ifdef CONFIG_HYPFS_CONFIG
> +static struct hypfs_entry_leaf config = {
> +    .e.type = XEN_HYPFS_TYPE_STRING,
> +    .e.encoding = XEN_HYPFS_ENC_GZIP,
> +    .e.name = "config",
> +    .e.read = hypfs_read_leaf,
> +    .content = &xen_config_data
> +};
> +#endif

Would be really good if no open-coded instantiations like this
one would ever have to appear, i.e. if suitable macros were
available. What's preventing use of one of the available ones
here?

Jan