[Qemu-devel] DOS VM problem with QEMU-KVM and newer kernels

[Gerhard Wiesinger]

Hello,

I'm having problems with recents kernels and qemu-kvm with a DOS VM:
TD286
System: Bad selector: 0007
System: Bad selector: 0D87
System: Bad selector: 001F
System: Bad selector: 0007
GP at 0020 21D4 EC 0DC4
Error 269 loading D:\BP\BIN\TD286.EXE into extended memory

Another 286 DOS Extender application also rises a general protection fault:
GP at 0020 18A1 CODE 357C

Doesn't depend on the used DOS memory manager and is always reproduceable.

Depends only on kernel version and not qemu-kvm and seabios (tried to 
bisect it without success):
# NOK: Linux 3.3.1-3.fc16.x86_64 #1 SMP Wed Apr 4 18:08:51 UTC 2012 
x86_64 x86_64 x86_64 GNU/Linux
# NOK: Linux 3.2.10-3.fc16.x86_64 #1 SMP Thu Mar 15 19:39:46 UTC 2012 
x86_64 x86_64 x86_64 GNU/Linux
# OK: Linux 3.1.9-1.fc16.x86_64 #1 SMP Fri Jan 13 16:37:42 UTC 2012 
x86_64 x86_64 x86_64 GNU/Linux
# OK: Linux 2.6.41.9-1.fc15.x86_64 #1 SMP Fri Jan 13 16:46:51 UTC 2012 
x86_64 x86_64 x86_64 GNU/Linux

CPU is an AMD one.

Any ideas how to fix it again?
Any switches which might help?

Thnx.

Ciao,
Gerhard