| 摘要 |
PROBLEM TO BE SOLVED: To control access to a predetermined memory address according to access control data. SOLUTION: Access to a memory address space is controlled by a memory control circuit using access control data. Authority to change the access control data is controlled by a domain control circuit. Whether or not an instruction stored within a particular domain being a set of memory addresses is able to modify the access control data is dependent upon the domain concerned. Thus, the authority to change access control data can be restricted to instructions stored within particular defined locations within the memory address space, thereby enhancing security. This authority allows systems to be provided in which call forwarding to an OS can be enforced via a call forwarding code, and the data concerned are accessible by trusted software executing under the control of a non-secure OS, and the trusted regions of the memory address space can be established. COPYRIGHT: (C)2009,JPO&INPIT |
