Bochs funny quirk

[Nessphoro]

In bochs I get this rather interesting situation,
After my V86 code, that finds the right video mode, is done running, sometimes I get this warning in the console window that goes as:
"kbd: OUTB set and command 0x20 encountered,"

Then the whole system hangs w.o. any error.

And also, if that doesn't occur, it still hangs right after the Video Mode is set.

In QEMU works without any problems.

[DLBuunk]

I remember that message from when i wrote my keyboard-driver, i forgot what it caused, though. I assume you use BIOS to work with video-modes (why else V86), so there might be a bug in bochs BIOS. The other possibility is that it bochs-BIOS expects a few things (IRQ vectors and such) set up differently than you gave it. It is OK in Qemu, you say, any clue what it does on real hardware?

[Nessphoro]

Haven't ran it on the real machine - yet.

[Bietje]

I remember that message from when i wrote my keyboard-driver, i forgot what it caused, though. I assume you use BIOS to work with video-modes (why else V86), so there might be a bug in bochs BIOS. The other possibility is that it bochs-BIOS expects a few things (IRQ vectors and such) set up differently than you gave it. It is OK in Qemu, you say, any clue what it does on real hardware?

I remember that I read somewhere that qemu uses the same BIOS image as bochs, so the bug couldn't be in the BIOS.

[stlw]

I remember that I read somewhere that qemu uses the same BIOS image as bochs, so the bug couldn't be in the BIOS.

In laterst version QEMU moved to SeaBIOS and Bochs still uses Bochs BIOS.
Bochs also supports SeaBIOS with SVN sources (but not in 2.4.6 release) so you can try Bochs with SeaBIOS and see if BIOS is really the issue.

Stanislav