On 2/27/2025 10:29 PM, Adrian Hunter wrote:
+ vcpu->arch.cr4 = ~vcpu->arch.cr4_guest_rsvd_bits;when userspace doesn't configure XFEATURE_MASK_PKRU in XFAM, it seems kvm_load_host_xsave_state() will skip restore host's PKRU value.That's correct.
FYI, in this case, it's safe and functional though kvm_load_host_xsave_state() skips restoring the host's PKRU value. Because host's PKRU is not clobbered after TD exit when XFAM.PKU is 0. So no need to restore.
