Google's Android emulator uses a virtual CPU that the company calls "Goldfish", which with Linux 3.9 is now supported by mainline. The X86_GOLDFISH kernel configuration option now provides, "Enable support for the Goldfish virtual platform used primarily for Android development."
Aside from supporting the Goldfish virtual Android emulator, this x86 platform pull request also adds in Technologic Systems TS-5500 platform support and improved NUMA support on AMD systems.
The x86 platform feature pull for Linux 3.9 can be found on the mailing list. Ingo Molnar also submitted already the 3.9 pull for x86 UV. This pull adds in support for the SGI Ultraviolet System 3 (UV3) platform. The Ultraviolet System 3 is SGI's forthcoming update to their super-computing platform.
Ingo also sent in the pull request for x86 HyperV. Microsoft's Hyper-V platform support for Linux now has support for Windows 8's improved hypervisor interrupt model.