Re: [PATCH v4] KVM: x86: Add x2APIC "features" to control EOI broadcast suppression

[Sean Christopherson]

On Fri, Dec 12, 2025, David Woodhouse wrote:
> On Thu, 2025-12-11 at 10:59 +0000, Khushit Shah wrote:
> And my intent was that the in-kernel I/O APIC patch gets included as
> *part* of this series, otherwise we're making a semantic change to the
> ENABLE behaviour later.

Hmm, my only concern on that front is that we'd be backporting effectively new
functionality to stable@ kernels that isn't strictly necessary.  But that's
probably fine given that it requires userspace to opt-in.

> Also... how does userspace discover the availability of these flags?

Ugh, yeah, I was reading too fast and overlooked that.  This needs a CAP.