The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 26, 2017
Filed:
Feb. 05, 2016
Apple Inc., Cupertino, CA (US);
Peter G. Soderquist, Milford, MA (US);
Pradeep Kanapathipillai, Santa Clara, CA (US);
Bernard J. Semeria, Palo Alto, CA (US);
Joshua P. de Cesare, Campbell, CA (US);
David J. Williamson, Austin, TX (US);
Gerard R. Williams, III, Los Altos, CA (US);
Apple Inc., Cupertino, CA (US);
Abstract
Systems, apparatuses, and methods for modifying access permissions in a processor. A processor may include one or more permissions registers for managing access permissions. A first permissions register may be utilized to override access permissions embedded in the page table data. A plurality of bits from the page table data may be utilized as an index into the first permissions register for the current privilege level. An attribute field may be retrieved from the first permissions register to determine the access permissions for a given memory request. A second permissions register may also be utilized to set the upper and lower boundary of a region in physical memory where the kernel is allowed to execute. A lock register may prevent any changes from being made to the second permissions register after the second permissions register has been initially programmed.