Re: [PATCH] libxl: check nesthvm and altp2m in libxl level

[Julien Grall <julien.grall@citrix.com>]

Hi Wei,

On 24/07/15 16:39, Wei Liu wrote:
> In ea214001 ("x86/altp2m: add altp2mhvm HVM domain parameter"), a
> check was added to ensure nestedhvm and altp2m cannot be enabled at
> the same time. That check was added in xl, but in fact it should be in
> libxl because it should be the entity that decides whether
> the provided configuration is valid.
> 
> This patch moves the check to libxl. The code snippet is moved after
> calling libxl__domain_build_info_setdefault so that we can:
> 1. remove libxl_defbool_is_default in `if()';
> 2. detect mistake in libxl__domain_build_info_setdefault.
> 
> Signed-off-by: Wei Liu <wei.liu2@citrix.com>
> ---
> Cc: Ed White <edmund.h.white@intel.com>
> Cc: "Sahita, Ravi" <ravi.sahita@intel.com>
> 
> I said I discovered an issue during review but also volunteered to fix
> it after the series is merged. Here is the patch to do that.
> ---
>  tools/libxl/libxl_create.c | 6 ++++++
>  tools/libxl/xl_cmdimpl.c   | 8 --------
>  2 files changed, 6 insertions(+), 8 deletions(-)
> 
> diff --git a/tools/libxl/libxl_create.c b/tools/libxl/libxl_create.c
> index 855b42c..de536ba 100644
> --- a/tools/libxl/libxl_create.c
> +++ b/tools/libxl/libxl_create.c
> @@ -883,6 +883,12 @@ static void initiate_domain_create(libxl__egc *egc,
>          goto error_out;
>      }
>  
> +    if (libxl_defbool_val(d_config->b_info.u.hvm.nested_hvm) &&
> +        libxl_defbool_val(d_config->b_info.u.hvm.altp2m)) {
> +        LOG(ERROR, "nestedhvm and altp2mhvm cannot be used together");
> +        goto error_out;
> +    }
> +

The u.hvm.{nested_hvm,altp2m} can only be checked when the created
domain is an HVM.

But initiate_domain_create is called with either a PV or HVM domain. So
you may need to check if we are creating a HVM one.

Regards,

-- 
Julien Grall