On Sat, Dec 11 2021 at 02:31, Paolo Bonzini wrote: > On 12/11/21 01:10, Thomas Gleixner wrote: >> 2) When the guest triggers #NM is takes an VMEXIT and the host >> does: >> >> rdmsrl(MSR_XFD_ERR, vcpu->arch.guest_fpu.xfd_err); >> >> injects the #NM and goes on. >> >> 3) When the guest writes to MSR_XFD_ERR it takes an VMEXIT and >> the host does: >> >> vcpu->arch.guest_fpu.xfd_err = msrval; >> wrmsrl(MSR_XFD_ERR, msrval); > > No wrmsrl here I think, the host value is 0 and should stay so. Instead > the wrmsrl will happen the next time the VCPU loop is entred. I assumed this can be handled in the fast path, but either way.
