Re: [PATCH v8 6/9] xen/arm: introduce CDF_staticmem

[Julien Grall <julien@xxxxxxx>]

Hi Penny,

On 07/07/2022 10:22, Penny Zheng wrote:
> In order to have an easy and quick way to find out whether this domain memory
> is statically configured, this commit introduces a new flag CDF_staticmem and a
> new helper is_domain_using_staticmem() to tell.
>
> Signed-off-by: Penny Zheng <penny.zheng@xxxxxxx>
> ---
> v8 changes:
> - #ifdef-ary around is_domain_using_staticmem() is not needed anymore
> ---
> v7 changes:
> - IS_ENABLED(CONFIG_STATIC_MEMORY) would not be needed anymore
> ---
> v6 changes:
> - move non-zero is_domain_using_staticmem() from ARM header to common
> header
> ---
> v5 changes:
> - guard "is_domain_using_staticmem" under CONFIG_STATIC_MEMORY
> - #define is_domain_using_staticmem zero if undefined
> ---
> v4 changes:
> - no changes
> ---
> v3 changes:
> - change name from "is_domain_static()" to "is_domain_using_staticmem"
> ---
> v2 changes:
> - change name from "is_domain_on_static_allocation" to "is_domain_static()"
> ---
>   xen/arch/arm/domain_build.c | 5 ++++-
>   xen/include/xen/domain.h    | 8 ++++++++
>   2 files changed, 12 insertions(+), 1 deletion(-)
>
> diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
> index 3fd1186b53..b76a84e8f5 100644
> --- a/xen/arch/arm/domain_build.c
> +++ b/xen/arch/arm/domain_build.c
> @@ -3287,9 +3287,12 @@ void __init create_domUs(void)
>           if ( !dt_device_is_compatible(node, "xen,domain") )
>               continue;
>   
> +        if ( dt_find_property(node, "xen,static-mem", NULL) )
> +            flags |= CDF_staticmem;
> +
>           if ( dt_property_read_bool(node, "direct-map") )
>           {
> -            if ( !IS_ENABLED(CONFIG_STATIC_MEMORY) || !dt_find_property(node, 
> "xen,static-mem", NULL) )
It is not clear to me why dropping IS_ENABLED(...) here is fine. What 
would happen if a user specify "xen,static-mem" in the device-tree but 
forgot CONFIG_STATIC_MEMORY in Xen?
Cheers,

--
Julien Grall