0992310b76
Protection for the `xgetbv` instruction for systems that do not support `xcr0` such as nehalem processors. The `XSAVE` cpuid indicates support for `XSAVE`, `XRESTOR`, `XSETBV`, `XGETBV` while `OSXSAVE` indicates if the operating system itself has `XSAVE` turned on. Both must be checked at the same time.