Granted Patent B2

US 9,280,491 · App. 14/715,196 · Granted Mar 8, 2016

Abstract

Claims (32)

1. A device comprising a memory management unit, the memory management unit comprising:

a first storage location to indicate physical address information mapping logical physical addresses to actual physical addresses,

the memory management unit to determine whether a write access to the first storage location is allowable, the access to store memory mapping information relating to a first actual physical address, the memory management unit to prevent the write access by a process that is running in or under a supervisor mode if the first actual physical address is not in an allowed address range of actual physical addresses, and to not prevent the write access to the first storage location by the process if the first actual physical address is in the allowed address range; and

a second storage location to indicate the allowed address range, the memory management unit to prevent a write access to the second storage location by a process that is not running in a hypervisor mode.

2. The device of claim 1 , wherein the memory mapping information is stored in a configuration memory region indicated by the second storage location.

3. The device of claim 1 , wherein the memory management unit is further to allow a read access to the memory mapping information by the process that is running in or under the supervisor mode.

4. The device of claim 1 , wherein the second storage location is to indicate allowed address ranges for two or more processes that are running in or under the supervisor mode.

5. The device of claim 1 , wherein the memory management unit further comprises a third storage location to indicate virtual address information mapping virtual addresses to physical addresses.

6. The device of claim 5 , wherein the third storage location is to indicate mapping a first virtual address to the first actual physical address.

7. The device claim 5 , wherein the memory management unit is further to allow a write access to the third storage location by the process that is running in or under the supervisor mode.

8. The device of claim 1 , wherein the first actual physical address is an address of a physical memory.

9. The device of claim 1 , wherein the memory management unit is further to allow a write access to the first storage location by a process that is running in the hypervisor mode.

10. A method comprising:

providing a first storage location at a memory management unit, the first storage location storing physical address information mapping logical physical addresses to actual physical addresses,

determining at the memory management unit whether a write access to the first storage location is allowable, the access to store memory mapping information relating to a first actual physical address, wherein the memory management unit prevents the write access by a process that is running in or under a supervisor mode if the first actual physical address is not in an allowed address range of actual physical addresses, and the memory management unit does not prevent the write access to the first storage location by the process if the first actual physical address is in the allowed address range; and

providing a second storage location at the memory management unit, the second storage location storing the allowed address range, wherein the memory management unit prevents a write access to the second storage location by a process that is not running in a hypervisor mode.

11. The method of claim 10 , wherein the memory mapping information is stored in a configuration memory region indicated by the second storage location.

12. The method of claim 10 , further comprising allowing a read access to the memory mapping information by the process that is running in or under the supervisor mode.

13. The method of claim 10 , further comprising the second storage location indicating allowed address ranges for two or more processes that are running in or under the supervisor mode.

14. The method of claim 10 , further comprising a third storage location at the memory management unit, the third storage location indicating virtual address information mapping virtual addresses to physical addresses.

15. The method of claim 14 , further comprising allowing a write access to the third storage location by a process that is running in or under the supervisor mode.

16. The method of claim 10 , wherein the first actual physical address is an address of a physical memory.

17. The method of claim 10 , further comprising allowing a write access to the first storage location of a process that is running in the hypervisor mode.

18. A system comprising:

a memory;

a first storage location to indicate physical address information mapping logical physical addresses to actual physical addresses;

a second storage location to indicate an allowed address range; and

a memory management unit coupled to the memory, the memory management unit to:

determine whether a write access to the first storage location, the access to store memory mapping information relating to a first actual physical address, the memory management unit to prevent the write access by a process that is running in or under a supervisor mode if the first actual physical address is not in the allowed address range of actual physical addresses, and to not prevent the write access to the first storage location by the process if the first actual physical address is in the allowed address range; and

prevent a write access to the second storage location by a process that is not running in a hypervisor mode.

19. The system of claim 18 , wherein the memory mapping information is stored in a configuration memory region indicated by the second storage location.

20. The system of claim 18 , wherein the memory management unit further comprises a third storage location to indicate virtual address information mapping virtual addresses to physical addresses.

Assignments (23)