Trouble with GDB debug stub and arm64 Linux guest

[rgov]

I'm going to give the "collecting support information" window until the end of writing this post to complete, but I can't tell if it's actually doing anything.

I have an Ubuntu 20.04 arm64 guest and I'm trying to debug the Linux kernel.

With debugStub.hideBreakpoints = "TRUE", when I set a breakpoint on a `ret` instruction I'm interested in, and continue, the kernel seems to enter a loop and the `ret` instruction breakpoint just gets hit again and again rather than control flow continuing forward.

If I set `debugStub.hideBreakpoints = "FALSE"`, upon connecting the debugger and continuing execution, the VM process seems to crash, and I need to restart VMware Fusion to boot the VM up again.

This is with Fusion Tech Preview 22H2.

Aside: I'm not sure if debugStub.listen.guest64.remote is supposed to work or not; I can't connect to the debug stub from another machine without using SSH port forwarding.

[Technogeezer]

Which kernel version is in use on the Ubuntu 20.04 installation?

Also, is Fusion reporting the crash as an error, or is the Linux kernel reporting a crash?

I'd collect a support bundle and contact VMware in any case. You might want to drop an email to fusion_beta@vmware.com for a more direct conversation with @Mikero and the development team. It also might not be a bad idea to drop a note in the Ubuntu forums. 

SSH port forwarding should IMO only be necessary if you have configured NAT (or "share with my Mac") networking. You shouldn't need port forwarding for a bridged network connection. 

[rgov]

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@Technogeezer wrote:

Which kernel version is in use on the Ubuntu 20.04 installation?

The kernel package was linux-image-5.4.0-26.

Also, is Fusion reporting the crash as an error, or is the Linux kernel reporting a crash?

Fusion itself was crashing. Not the UI but the backend virtualization process.