How do I write x86 Debug registers from user space on OSX?
- by nall
I'd like to play around with the debug MSRs defined in the x86 spec (DR0-7) from my OSX user-space program. Unfortunately, these require CPL == 0 (aka ring 0). I've thumbed through the OSX syscalls and with the exception of kernel_debug nothing really jumps out as a way to access these.
It may be the case that they are only available via some higher level interface like kernel_debug, but it's unclear to me if that's the case or if I just haven't found the magic invocation to get to them.
Anyone know how to do this?