Predetermined less-secure memory property

• Main Authors: Carlos Garcia-Tobin, Alexander Donald Charles Chadwick, Jason Parker, Yuval Elad
• Format: Patent
• Language: English
• Published: 28.08.2024
• Subjects: CALCULATING; COMPUTING; COUNTING; ELECTRIC DIGITAL DATA PROCESSING; PHYSICS

Disclose is an apparatus with address translation circuitry 16 to translate a target virtual address of a memory access request to a target physical address. The memory access request is associated with a processing domain, the domains including a less secure domain associated with a less secure physical address space (PAS) and a more secure domain associated with a more secure PAS. There is PAS selection circuitry to select a selected PAS for the memory access request from among the PAS including the less secure PAS and the more secure PAS, the more secure PAS being prohibited from being selected for memory access requests associated with the less secure domain. Checking circuitry 20 determines whether to reject the memory access request based on protection information corresponding to the target physical address, the protection information specifying which of the PAS is allowed to provide access to the target physical address. In one mode of operation, in response to determining that the protection information corresponding to the target physical address indicates a predetermined less-secure memory property, the checking circuitry is configured to determine that, the less secure PAS is allowed to provide access to the target physical address, the more secure PAS is prohibited from providing access to the target physical address, and memory access requests associated with the more secure domain are prohibited from accessing the target physical address, even when the selected PAS is the less secure PAS.