- Implement KiExceptionExit, which works like KiServiceExit2, but takes an exception frame as 2nd parameter
- Add a local exception frame to NtRaiseException and NtContinue, which is needed to exit with a full context on x64 and arm
- Use KeContextToTrapFrame again instead of KiSetTrapContext, since we have a proper exception frame now.
This is used in KiUserModeCallout instead of KiServiceExit2. The latter is broken, leaks non-volatile registers and will need to be modified to handle an exception frame, which we don't need/have here. It will also use sysret instead of iret and is generally simpler/faster.
Eventually it would be desirable to skip the entire trap frame setup and do everything in KiCallUserMode. This requires some cleanup and special handling for user APC delivery.
Co-authored-by: Victor Perevertkin <victor.perevertkin@reactos.org>
Introduce the initial changes needed to get other processors up and into kernel mode.
This only supports x86 as of now but is the first real step towards using other system processors.
