Re: [PATCH v2 1/4] x86: provide an inverted Kconfig control for shim-exclusive mode

[Roger Pau Monné <roger.pau@xxxxxxxxxx>]

On Thu, Jan 16, 2025 at 04:31:46PM -0800, Stefano Stabellini wrote:
> On Wed, 1 Mar 2023, Jan Beulich wrote:
> > While we want certain things turned off in shim-exclusive mode, doing
> > so via "depends on !PV_SHIM_EXCLUSIVE" badly affects allyesconfig: Since
> > that will turn on PV_SHIM_EXCLUSIVE, other options will be turned off as
> > a result. Yet allyesconfig wants to enable as much of the functionality
> > as possible.
> > 
> > Retain PV_SHIM_EXCLUSIVE as a prompt-less option such that first of all
> > C code using it can remain as is. This isn't just for less code churn,
> > but also because I think that symbol is more logical to use in many
> > (all?) places.
> > 
> > Requested-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
> > Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
> >
> > ---
> > The new Kconfig control's name is up for improvement suggestions, but I
> > think it's already better than the originally thought of
> > FULL_HYPERVISOR.
> 
> I think the approach in general is OK, maybe we can improve the naming
> further. What about one of the following?
> 
> NO_PV_SHIM_EXCLUSIVE
> PV_SHIM_NOT_EXCLUSIVE

IMO negated options are confusing, and if possible I think we should
avoid using them unless strictly necessary.

I for example always considered extremely confusing that previous to
having CONFIG_DEBUG Xen used NDEBUG (so no debug) as a way to signal
debug vs non-debug builds.

Thanks, Roger.