On Thu, Aug 25, 2022, Chang S. Bae wrote: > On 8/25/2022 9:19 AM, Sean Christopherson wrote: > > > > Adding new uAPI and new exports to eliminate one line of userspace code is not a > > good tradeoff. Am I missing something? This really seems like solution looking > > for a problem. > > Well, then that's your call. > > Yeah, that simplification is really minor. With this, I would rather think > KVM wants enforcement before relaying the request to the host. That > enforcement is unthinkable without supported_xcr0. My point is that KVM needs supported_xcr0 (or similar behavior) regardless of whether or not the kernel further restricts feature usage. > But it looks like userspace is somehow trusted here for KVM.
