SVC: Difference between revisions

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Lastly, the kernel disables the specified (B/W)RP, then writes the value parameter / loaded contextID to the (B/W)VR, then writes the input control value to the (B/W)CR.

~~= Processes =~~

Each process is given an array of [[NCCH/Extended_Header#ARM11_Kernel_Capabilities|kernel capability descriptors]] upon creation (see CreateProcess). Official software forwards the descriptors specified in the [[NCCH#Extended_Header|NCCH exheader]].

Any process can only use SVCs which are enabled in its kernel capability descriptors. This is enforced by the ARM11 kernel SVC handler by checking the syscall access control mask stored on the SVC-mode stack. If the SVC isn't enabled, a kernelpanic() is triggered. Each process has a separate SVC-mode stack; this stack and the syscall access mask stored here are initialized when the process is started. Applications normally only have access to SVCs <=0x3D, however not all SVCs <=0x3D are accessible to the application. The majority of the SVCs accessible to applications are unused by the application.

Each process has a separate handle-table, the size of which is stored in the kernel capability descriptor. The handles in a handle-table can't be used in the context of other processes, since those handles don't exist in other handle-tables.

~~0xFFFF8001 is a handle alias for the current KProcess, and 0xFFFF8000 is a handle alias for the current KThread.~~

~~Calling svcBreak on retail will only terminate the process which called this SVC.~~

= Threads =

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 Lastly, the kernel disables the specified (B/W)RP, then writes the value parameter / loaded contextID to the (B/W)VR, then writes the input control value to the (B/W)CR.
-= Processes =
-Each process is given an array of [[NCCH/Extended_Header#ARM11_Kernel_Capabilities|kernel capability descriptors]] upon creation (see CreateProcess). Official software forwards the descriptors specified in the [[NCCH#Extended_Header|NCCH exheader]].
-Any process can only use SVCs which are enabled in its kernel capability descriptors. This is enforced by the ARM11 kernel SVC handler by checking the syscall access control mask stored on the SVC-mode stack. If the SVC isn't enabled, a kernelpanic() is triggered. Each process has a separate SVC-mode stack; this stack and the syscall access mask stored here are initialized when the process is started. Applications normally only have access to SVCs <=0x3D, however not all SVCs <=0x3D are accessible to the application. The majority of the SVCs accessible to applications are unused by the application.
-Each process has a separate handle-table, the size of which is stored in the kernel capability descriptor. The handles in a handle-table can't be used in the context of other processes, since those handles don't exist in other handle-tables.
-xFFFF8001 is a handle alias for the current KProcess, and 0xFFFF8000 is a handle alias for the current KThread.
-Calling svcBreak on retail will only terminate the process which called this SVC.
 = Threads =