DESQview/X 2.10 critical error running under VB 7.0.4

[jtfolden]

I have created a VM to run DESQview/X but it crashes wile attempting to run DVX itself.

It is running IBM PC-DOS 2000. I have installed Windows 3.11, QEMM, DESQview/X 2.10, and also the DVX TCPIP Network software. Everything is fine except for DV/X itself. I see the logo screen and then the VM crashes (presumably at the point it would start it's GUI).

The log is attached. VB 7.0.4 is running under macOS Monterey 12.6.2 on a Mac mini (Late 2014).

Any/all help appreciated.

[mpack]

The guru error code is VERR_EM_INTERPRETER. I've never seen it before, but I imagine it refers to a raw mode emulation of an unusual processor instruction. Unfortunately raw mode doesn't exist on MacOS hosts so either my guess is wrong or that guest code is incompatible with your host.

What CPU(s) does DVX support? It's possible that it's relying on an obscure CPU feature that no longer exists. ISTR DESQview had a reputation for using obscure CPU features to boost performance.

[fth0]

The guru error code is VERR_EM_INTERPRETER. I've never seen it before, but I imagine it refers to a raw mode emulation of an unusual processor instruction. Unfortunately raw mode doesn't exist on MacOS hosts so either my guess is wrong or that guest code is incompatible with your host.

I think you're on the right track here. AFAICS, the VERR_EM_INTERPRETER error is triggered in several distinct situations:

One possible situation is that the IEM (Interpreted Execution Manager) couldn't emulate the current CPU instruction. But the latter seems to be the classical IRET (0xcf) instruction here, so I'd assess that with a low possibility.

Another possible situation is some new VT-x related "Code template for our own hypervisor and the NEM darwin backend using Apple's Hypervisor.framework" in VirtualBox 7.0. Since this matches the issue at hand quite well, I'd suggest taking the following approach:

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Any/all help appreciated.

Uninstall VirtualBox 7.0.4, reboot the host and install VirtualBox 6.1.40. Try if that already solves the problem. If not, provide another (zipped) VBox.log file. Additionally, you can try limiting the virtual CPU provided to the guest by VirtualBox 6.1.40 with the following command:

Code: Select all

VBoxManage modifyvm "VM name" --cpu-profile "intel 80386"

If needed, you can undo this setting with:

Code: Select all

VBoxManage modifyvm "VM name" --cpu-profile "host"

[jtfolden]

What CPU(s) does DVX support? It's possible that it's relying on an obscure CPU feature that no longer exists. ISTR DESQview had a reputation for using obscure CPU features to boost performance.

DV/X requires a 386SX or later. I know it also ran on 486 and Pentium level CPU's (as that is what I used originally back in the 1990s to run it). I already have DV/X successfully running under UTM (QEMU based app for Mac) but UTM is not great for running a lot of other OS's, I'm finding out.

Uninstall VirtualBox 7.0.4, reboot the host and install VirtualBox 6.1.40. Try if that already solves the problem.

Are VM's created under v7 usable with 6.1?

[fth0]

Are VM's created under v7 usable with 6.1?

As long as they are not configured to use a feature that didn't exist in VirtualBox 6.1.40 (e.g. TPM, macOS Ventura, ...).