[CRIU] [PATCH 1/4] syscall: add memfd_create()

[Pavel Emelyanov]

Would you also

> @@ -232,6 +233,8 @@ int kerndat_init(void)
>  	if (!ret)
>  		ret = get_last_cap();
>  
> +	kerndat_has_memfd_create();

Fail the kerndat_init() in case sys_memfd_create
reported some "real" error?

> +
>  	return ret;
>  }
>  
> @@ -251,3 +254,18 @@ int kerndat_init_rst(void)
>  
>  	return ret;
>  }
> +
> +bool kerndat_has_memfd_create(void)
> +{
> +	static int supported = -1;

Follow the kerndat style that "features" are described
just by global boolean variables. I have plans to collect
all this stuff into a structure.

> +	int ret;
> +
> +	if (supported != -1)
> +		return !!supported;
> +
> +	ret = sys_memfd_create(NULL, 0);
> +	supported = (ret != -ENOSYS);
> +
> +	return !!supported;
> +}
> +
>