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51 bytes added ,  21:32, 27 July 2014
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For svcCreateThread the input address used for Entrypoint_Param and StackTop are normally the same, however these can be arbitrary. For the main thread the Entrypoint_Param is value 0.
 
For svcCreateThread the input address used for Entrypoint_Param and StackTop are normally the same, however these can be arbitrary. For the main thread the Entrypoint_Param is value 0.
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Using CloseHandle() with a KThread handle will terminate the specified thread.
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Using CloseHandle() with a KThread handle will terminate the specified thread, only if the reference count reaches 0.
    
= Memory Mapping =
 
= Memory Mapping =
ControlMemory and MapMemoryBlock can be used to map memory pages, these two SVCs only support mapping execute-never R/W pages. The input permissions parameter for these SVCs must be <=3, where value zero is used when un-mapping memory. Bitmask 0xf00 for ControlMemory parameter MemoryType is the memory-type, when this is zero the memory-type is loaded from the kernel flags stored in the exheader ARM11 kernel descriptors, for the process using the SVC. ControlMemory parameter MemoryType with value 0x10003 is used for mapping the GSP [[Memory_layout|heap]]. The low 8-bits are the type: 1 is for un-mapping memory, 3 for mapping memory. Type4 is used to mirror the RW memory at Addr1, to Addr0. Type4 will return an error if Addr1 is located in read-only memory. Addr1 is not used for type1 and type3.
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ControlMemory and MapMemoryBlock can be used to map memory pages, these two SVCs only support mapping execute-never R/W pages. The input permissions parameter for these SVCs must therefore be <=3, where value zero is used when un-mapping memory.
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Bitmask 0xF00 for ControlMemory parameter MemoryType is the memory-type, when this is zero the memory-type is loaded from the kernel flags stored in the exheader ARM11 kernel descriptors, for the process using the SVC.
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ControlMemory parameter MemoryType with value 0x10003 is used for mapping the GSP [[Memory_layout|heap]]. The low 8-bits are the type: 1 is for un-mapping memory, 3 for mapping memory. Type4 is used to mirror the RW memory at Addr1, to Addr0. Type4 will return an error if Addr1 is located in read-only memory. Addr1 is not used for type1 and type3.
    
The ARM11 kernel does not allow processes to create shared memory blocks via svcCreateMemoryBlock, when the process memorytype(from the kernel flags stored in the exheader kernel descriptor) is the application memorytype, and when addr=0. It's unknown how the kernel handles addr=0 when the memorytype is not the application memorytype. When addr is non-zero, it must be located in memory which is already mapped.
 
The ARM11 kernel does not allow processes to create shared memory blocks via svcCreateMemoryBlock, when the process memorytype(from the kernel flags stored in the exheader kernel descriptor) is the application memorytype, and when addr=0. It's unknown how the kernel handles addr=0 when the memorytype is not the application memorytype. When addr is non-zero, it must be located in memory which is already mapped.
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= SVC7B Backdoor =
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= svc7B Backdoor =
 
This saves SVC-mode SP+LR on the user-mode stack, then sets the SVC-mode SP to the user-mode SP. This then calls the specified code in SVC-mode. Once the called code returns, this pops the saved SP+LR off the stack for restoring the SVC-mode SP, then returns from the svc7b handler. Note that this svc7b handler does not disable IRQs, if any IRQs/context-switches occur while the SVC-mode SP is set to the user-mode one here, the ARM11-kernel will crash(which hangs the whole ARM11-side system).
 
This saves SVC-mode SP+LR on the user-mode stack, then sets the SVC-mode SP to the user-mode SP. This then calls the specified code in SVC-mode. Once the called code returns, this pops the saved SP+LR off the stack for restoring the SVC-mode SP, then returns from the svc7b handler. Note that this svc7b handler does not disable IRQs, if any IRQs/context-switches occur while the SVC-mode SP is set to the user-mode one here, the ARM11-kernel will crash(which hangs the whole ARM11-side system).