On Tue, Sep 05, 2023, Jari Ruusu wrote: > On Tuesday, September 5th, 2023 at 22:27, Sean Christopherson <seanjc@xxxxxxxxxx> wrote: > > As for working around this in your setup, assuming you don't actually need a > > virtual PMU in the guest, the simplest workaround would be to turn off vPMU > > support in KVM, i.e. boot with kvm.enable_pmu=0. That should cause QEMU to not > > advertise a PMU to the guest. > > Newer host kernels seem to have kvm.enable_pmu parameter, > but linux-5.10.y kernels do not have that. Gah, try kvm.pmu. Commit 4732f2444acd ("KVM: x86: Making the module parameter of vPMU more common") renamed the variable to avoid collisions, but it unnecessarily changed the name exposed to userspace too. My gut reaction is to revert the param name back to "pmu". Paolo, any idea if reverting "enable_pmu" back to "pmu" would be worth the churn?