Memory layout: Difference between revisions
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| 0x1FF80000 | | 0x1FF80000 | ||
| | | 0x1000 | ||
| [[Configuration Memory]], access to this is specified by the exheader as | | [[Configuration Memory]], all processes have access to this however write-permission to this page is specified by the exheader "Shared page writing" kernel flag. | ||
|- | |||
| 0x1FF81000 | |||
| 0x1000 | |||
| Shared page, access to this is the same as 0x1FF80000. | |||
|} | |} | ||
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-. | ||