Re: [PATCH v19 027/130] KVM: TDX: Define TDX architectural definitions

[Isaku Yamahata]

On Wed, Apr 03, 2024 at 08:04:03AM -0700,
Sean Christopherson <seanjc@xxxxxxxxxx> wrote:

> On Mon, Feb 26, 2024, isaku.yamahata@xxxxxxxxx wrote:
> > +union tdx_vcpu_state_details {
> > +	struct {
> > +		u64 vmxip	: 1;
> > +		u64 reserved	: 63;
> > +	};
> > +	u64 full;
> > +};
> 
> No unions please.  KVM uses unions in a few places where they are the lesser of
> all evils, but in general, unions are frowned upon.  Bitfields in particular are
> strongly discourage, as they are a nightmare to read/review and tend to generate
> bad code.
> 
> E.g. for this one, something like (names aren't great)
> 
> static inline bool tdx_has_pending_virtual_interrupt(struct kvm_vcpu *vcpu)
> {
> 	return <get "non arch field"> & TDX_VCPU_STATE_VMXIP;
> }


Sure, let me replace them with mask and shift.
-- 
Isaku Yamahata <isaku.yamahata@xxxxxxxxx>