On Wed, Jun 29, 2022 at 2:06 AM Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> wrote: > For PERF_GLOBAL_CTRL errata: > - We can move the filtering to vmx_vmexit_ctrl()/vmx_vmentry_ctrl() > preserving the status quo: KVM doesn't use the feature but it is exposed > to L1 hypervisor (and L1 hypervisor presumably has the same check and > doesn't use the feature. FWIW, the workaround was added in 2011 and the > erratas it references appeared in 2010, this means that the affected > CPUs are quite old, modern proprietary hypervisors won't likely boot > there). Sadly, Nehalem and Westmere are well-supported by KVM today, and we will probably still continue to support them for at least another decade. They both have EPT, unrestricted guest, and other VT-x2 features that KVM still considers optional.
