Intel C2518 FH8065501516710 Data Sheet

Intel

®

 Atom™ Processor C2000 Product Family for Microserver

September 2014

Datasheet, Vol. 1 of 3

Order Number: 330061-002US

49

• Extended Page Tables (EPT)

— An EPT is hardware-assisted page table physical memory virtualization.
— The feature supports guest VM execution in unpaged protected mode or in real-

address mode.

— EPT eliminates VM exits from guest OS to the VMM for shadow page-table 

maintenance.

• Virtual Processor IDs (VPID)

— The ability to use an assigned VM Virtual Processor ID to tag processor core 

hardware structures (such as TLBs) allowing a logic processor to cache 

information (such as TLBs) for multiple-linear address spaces.

— This avoids flushes on VM transitions to give a lower-cost VM transition time 

and an overall reduction in virtualization overhead.

• Guest Preemption Timer

— A mechanism for a VMM to preempt the execution of a guest OS VM after an 

amount of time specified by the VMM. The VMM sets a timer value before 

entering a guest.

— The feature aids VMM developers in flexibility and Quality of Service (QoS) 

guarantees flexibility in guest VM scheduling and building QoS schemes.

• Descriptor-Table Exiting

— Descriptor-table exiting allows a VMM to protect a guest OS from internal 

(malicious software based) attack by preventing relocation of key system data 

structures like Interrupt Descriptor Table (IDT), Global Descriptor Table (GDT), 

Local Descriptor Table (LDT), and Task Segment Selector (TSS).

— A VMM using this feature intercepts (by a VM exit) attempts to relocate these 

data structures and prevent them from being tampered by malicious software.

• VM Functions

— A VM function is an operation provided by the processor that is invoked using 

the VMFUNC instruction from guest VM without a VM exit.

— A VM function to perform EPTP switching is supported and allows guest VM to 

load a new value for the EPT pointer, thereby establishing a different EPT 

paging structure hierarchy.