On Fri, Apr 23, 2021 at 5:51 PM Sean Christopherson <seanjc@xxxxxxxxxx> wrote: > > Remove a bogus write to vcpu->arch.cr0 that immediately precedes > vmx_set_cr0() during vCPU RESET/INIT. For RESET, this is a nop since > the "old" CR0 value is meaningless. But for INIT, if the vCPU is coming > from paging enabled mode, crushing vcpu->arch.cr0 will cause the various > is_paging() checks in vmx_set_cr0() to get false negatives. > > For the exit_lmode() case, the false negative is benign as vmx_set_efer() > is called immediately after vmx_set_cr0(). > > For EPT without unrestricted guest, the false negative will cause KVM to > unnecessarily run with CR3 load/store exiting. But again, this is > benign, albeit sub-optimal. > > Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx> Reviewed-by: Reiji Watanabe <reijiw@xxxxxxxxxx>
