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.
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.
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.
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.