Re: [PATCH v4 27/30] KVM: x86: Add KVM_VCPU_TSC_EFFECTIVE_FREQ attribute

[Sean Christopherson]

On Thu, May 21, 2026, David Woodhouse wrote:
> On Sat, 2026-05-09 at 23:46 +0100, David Woodhouse wrote:
> > From: David Woodhouse <dwmw@xxxxxxxxxxxx>
> That does leave userspace still needing a way to get the APIC bus
> frequency, to populate CPUID. So maybe I'll just make an attribute
> which returns that as a single value.

Already exists, KVM_CAP_X86_APIC_BUS_CYCLES_NS.  The TDX architecture decided
that unconditionally telling guests the virtual APIC bus runs at 400Mhz was a
brilliant idea.