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→ARM11 User-land memory regions
All executable pages are read-only, and data pages have the execute-never permission set. Normally .text from the loaded ExeFS:/.code is the only mapped executable memory. Executable [[RO Services|CROs]] can be loaded into memory, once loaded the CRO .text section memory page permissions are changed via [[SVC|ControlProcessMemory]] from RW- to R-X. The address and size of each ExeFS:/.code section is stored in the exheader, the permissions for each section is: .text R-X, .rodata R--, .data RW-, and .bss RW-. The loaded .code is mapped to the addresses specified in the exheader by the ARM11 kernel. The stack permissions is initialized by the ARM11 kernel: RW-. The heap permissions is normally RW-.
All executable pages are read-only, and data pages have the execute-never permission set. Normally .text from the loaded ExeFS:/.code is the only mapped executable memory. Executable [[RO Services|CROs]] can be loaded into memory, once loaded the CRO .text section memory page permissions are changed via [[SVC|ControlProcessMemory]] from RW- to R-X. The address and size of each ExeFS:/.code section is stored in the exheader, the permissions for each section is: .text R-X, .rodata R--, .data RW-, and .bss RW-. The loaded .code is mapped to the addresses specified in the exheader by the ARM11 kernel. The stack permissions is initialized by the ARM11 kernel: RW-. The heap permissions is normally RW-.
All userland memory is mapped with RW permissions for privileged-mode. However, normally the ARM11 kernel only uses userland read/write instructions(or checks that the memory can be written from userland first) for accessing memory specified by [[SVC|SVCs]].