公开(公告)号：GB2523280A

公开(公告)日：2015-08-19

申请号：GB201509633

申请日：2013-06-17

Applicant: INTEL CORP

Inventor： LIU BAOHONG ,  SOOD RITU ,  TSENG KUO-LANG ,  TALLAM DUKE

IPC: G06F12/10 ,  G06F12/14

Abstract: Embodiments of an invention for controlling access to groups of memory pages in a virtualized environment are disclosed. In one embodiment, a processor includes a virtualization unit and a memory management unit. The virtualization unit is to transfer control of the processor to a virtual machine. The memory management unit is to perform, in response to an attempt to execute on the virtual machine an instruction stored on a first page, a page walk through a paging structure to find a second page and to allow access to the second page without exiting the virtual machine based at least in part on a bit being set in a leaf level entry corresponding to the second page in the paging structure and a corresponding bit being set in each entry corresponding to the first page in each level of the paging structure.

公开(公告)号：EP2801026A4

公开(公告)日：2015-08-12

申请号：EP12864359

申请日：2012-01-04

Applicant: INTEL CORP

Inventor： LIU BAOHONG ,  CASTELINO MANOHAR R ,  TSENG KUO-LANG ,  SOOD RITU ,  TALLAM MADHUKAR

IPC: G06F9/30 ,  G06F9/44 ,  G06F9/455 ,  G06F12/08 ,  G06F12/14

CPC classification number: G06F12/145 ,  G06F9/45558 ,  G06F2009/45583

Abstract: Embodiments of techniques and systems for using substitute virtualized-memory page tables are described. In embodiments, a virtual machine monitor (VMM) may determine that a virtualized memory access to be performed by an instruction executing on a guest software virtual machine is not allowed in accordance with a current virtualized-memory page table (VMPT). The VMM may select a substitute VMPT that permits the virtualized memory access. In scenarios where a data access length for the instruction is known, the substitute VMPT may include full execute, read, and write permissions for the entire guest software address space. In scenarios where a data access length for the instruction is not known, the substitute VMPT may include less than full execute, read, and write permissions for the entire guest software address space, and may be modified to allow the requested virtualized memory access. Other embodiments may be described and claimed.

公开(公告)号：EP2801025A4

公开(公告)日：2015-08-26

申请号：EP12864336

申请日：2012-01-04

Applicant: INTEL CORP

Inventor： THOMAS RAMESH ,  TSENG KUO-LANG ,  SAHITA RAVI L ,  DURHAM DAVID M ,  TALLAM MADHUKAR

IPC: G06F9/30 ,  G06F9/46 ,  G06F12/08 ,  G06F12/14 ,  G06F15/80

CPC classification number: G06F12/145 ,  G06F9/468 ,  G06F12/1425 ,  G06F2009/45583 ,  G06F2009/45587

Abstract: Embodiments of techniques and systems for increasing efficiencies in computing systems using virtual memory are described. In embodiments, instructions which are located in two memory pages in a virtual memory system, such that one of the pages does not permit execution of the instructions located therein, are identified and then executed under temporary permissions that permit execution of the identified instructions. In various embodiments, the temporary permissions may come from modified virtual memory page tables, temporary virtual memory page tables which allow for execution, and/or emulators which have root access. In embodiments, per-core virtual memory page tables may be provided to allow two cores of a computer processor to operate in accordance with different memory access permissions. In embodiments, a physical page permission table may be utilized to provide for maintenance and tracking of per-physical-page memory access permissions. Other embodiments may be described and claimed.