The following issues were reported when trying to implement a debug solution for MicroBlaze in the Linux:
1. Linux can crash or freeze MicroBlaze when stopping and continuing. This is caused by MMU instruction exceptions that occur when stopping not being blocked. There is also an issue with stepping an instruction that causes an exception, which makes MicroBlaze continue execution instead of stopping, since the debug logic does not halt MicroBlaze after the exception.
2. The debugger cannot invalidate caches or access special registers when it is in User Mode. It is been changed so that the debugger is allowed to do this.
These issues have been fixed in the latest release of MicroBlaze in EDK 10.1 Service Pack 2 available at:
http://www.xilinx.com/xlnx/xil_sw_updates_home.jsp