illumos gate

In bhyve, the access/attributes of the various segments (%[cdefgs]s, %ldtr, %tr) is exposed though the ioctl API from the internal state of the VMCS/VMCB. The effective format of that data follows how it is defined by Intel for the VMCS, but there are no visible header definitions for it. The data is manually manipulated instead, which is potentially brittle and a poor situation for alternative userspace consumers which may come along.

It would be nice to write up some header defines for those access/attribute bits, and have both kernel-space and userspace bhyve use them.