On Tue, 2023-04-04 at 21:09 +0800, Binbin Wu wrote: > case VMX_VPID_EXTENT_INDIVIDUAL_ADDR: > + /* invvpid is not valid in compatibility mode */ > + if (is_long_mode(vcpu)) > + operand.gla = vmx_untag_addr(vcpu, operand.gla, 0); This comment doesn't make sense. The code does nothing to distinguish the compatibility mode and the 64-bit mode. Now although we are all clear that here is_long_mode() basically equals to is_64_bit_mode(), but I do think we need a comment or WARN() _SOMEWHERE_ to indicate that compatibility mode is not possible when handling VMEXIT for VMX instructions (except VMCALL). Not everyone will be able to notice this small thing in the SDM. Then you can just delete this comment here. Alternatively, for better readability actually I am thinking maybe we should just use is_64_bit_mode(), because those segments are cached by KVM anyway so I don't think there's measurable performance difference between is_long_mode() and is_64_bit_mode(). Sean, any comments?
