On Wed, Sep 23, 2020 at 07:07:22PM +0200, Paolo Bonzini wrote: > On 23/09/20 18:36, Sean Christopherson wrote: > > +static inline bool pt_output_base_valid(struct kvm_vcpu *vcpu, u64 base) > > +{ > > + /* The base must be 128-byte aligned and a legal physical address. */ > > + return !(base & (~((1UL << cpuid_maxphyaddr(vcpu)) - 1) | 0x7f)); > > +} > > The fact that you deemed a comment necessary says something already. :) > What about: > > return !kvm_mmu_is_illegal_gpa(vcpu, base) && !(base & 0x7f); > > (where this new usage makes it obvious that mmu should have been vcpu). Ya. I think it was a sort of sunk cost fallacy. Dammit, I spent all that time figuring out what this code does, I'm keeping it!!! v3 incoming...