I'd like to use QEMU to emulate an MS-DOS system that will run a very specific proprietary software that needs to talk to a SCSI tape device.
I see that QEMU offers passthrough access to the host SCSI bus, and it looks like it can also emulate a SCSI adapter that the guest OS can use. But I have very little experience setting up QEMU with SCSI, and the documentation is a bit dense/convoluted.
Here is my QEMU command line so far:
qemu-system-i386 -m 32 -drive file="dosdrive.img",format=raw \ -option-rom "8xx_64.ROM" \ -drive file=/dev/sg2,if=scsi,bus=0,unit=0,format=raw \ -device dc390
The emulated BIOS definitely sees the tape drive:
...and it looks like DOS successfully loads the ASPI driver. But then, when the software actually tries reading from the SCSI device, it hangs, and I see these errors coming from QEMU:
lsi_scsi: error: Unhandled writeb 0xbc = 0x0 lsi_scsi: error: IO mappings not implemented
Does this mean I'm out of luck, and QEMU can't work with a SCSI tape drive? Or do I have a problem in my configuration?