Is ARM (not Thumb) supported on WinPhone8 at all?

Question

I\'m facing a weird issue, somewhat similar to this. I have a Windows Phone 8 native DLL project, mostly C++ but with an ARM assembly source in it. The source is in ARM mode

Answer 1

I have firsthand knowledge of this; I was the reverse engineer who figured out the cause in Windows RT's kernel. Specifically, KeContextFromKframes in the Windows NT kernel (ntoskrnl.exe) is setting the T bit when freezing a thread's state for a task switch. This means that yes, upon resuming after an interrupt, you will crash.

This annoyed us jailbreakers for RT/WinPhone, because we couldn't directly port Chrome's JITter without breaking Microsoft's PatchGuard. We could load a kernel driver to patch this out of KeContextFromKframes, but then PatchGuard would later cause a crash.