[Qemu-devel] Re: Bug in emulation of 'bound' x86 instruction?

[Stefan Kisdaroczi]

Hi all,

While testing my "DOS+Realtime Multitasking Extension" Images ( working 
with bochs ), two things did not work with qemu :

1) The BOUND instruction seems to raise always the Exception 5
if the second Parameter is a location in the cs seg.
Example: bound di, cs:1095

2) An Exception 13 is raised when a "les" instruction should get the 
seg:ofs pair from the ss seg.
Example: les di, ss:si+10

-> im not really sure if its really dependent of the used seg, but i 
have started multiple programs, and all crash on different locations 
always on the bound or les instructions. It was always cs used in case 
1) and ss used in case 2).

The system is running in mixed 16/32 Bit Protected mode. It happens in a 
16-bit code segment.

The System debugger starts automatically on the exceptions 5 and 13, so 
i have looked at the memory locations referred and the values there are 
correct.

What can i do to help you helping me ?

Thank you.

Greetings kisda