Re: [PATCH for-4.16] tests/resource: set grant version for created domains

[Jan Beulich <jbeulich@xxxxxxxx>]

On 15.11.2021 11:51, Roger Pau Monne wrote:
> Set the grant table version for the created domains to use version 1,
> as that's the used by the test cases. Without setting the grant
> version the domains for the tests cannot be created.
> 
> Fixes: 7379f9e10a ('gnttab: allow setting max version per-domain')
> Reported-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
> Signed-off-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>

Technically
Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>

However, two remarks:

> --- a/tools/tests/resource/test-resource.c
> +++ b/tools/tests/resource/test-resource.c
> @@ -120,6 +120,7 @@ static void test_domain_configurations(void)
>              .create = {
>                  .max_vcpus = 2,
>                  .max_grant_frames = 40,
> +                .grant_opts = 1,
>              },
>          },
>          {
> @@ -128,6 +129,7 @@ static void test_domain_configurations(void)
>                  .flags = XEN_DOMCTL_CDF_hvm,
>                  .max_vcpus = 2,
>                  .max_grant_frames = 40,
> +                .grant_opts = 1,
>                  .arch = {
>                      .emulation_flags = XEN_X86_EMU_LAPIC,
>                  },
> @@ -140,6 +142,7 @@ static void test_domain_configurations(void)
>                  .flags = XEN_DOMCTL_CDF_hvm | XEN_DOMCTL_CDF_hap,
>                  .max_vcpus = 2,
>                  .max_grant_frames = 40,
> +                .grant_opts = 1,
>              },
>          },
>  #endif

The literal 1-s here are really odd to read already now. It would get
worse if some flags were specified later on and then used here, ending
in e.g.

                .grant_opts = XEN_DOMCTL_CDG_feature | 1,

Imo there really ought to be a wrapper macro, such that use sites
will at the same time have documented what this 1 is about:

                .grant_opts = XEN_DOMCTL_CDG_version(1),

And then I guess tools/tests/tsx/test-tsx.c needs similar adjustment.

Jan