Kernel Panic upgrading from Monterey 12.0.1 to 12.02

[enigma0456]

Have successfully upgraded from the original Catalina through Big Sur and to Monterey until this. VirtualBox with 2 cpus and 8 gb ram allocated. Continuous kernel panics when trying this latest upgrade on two different machines and hosts. Reading comments here I reduced the machine to 1 cpu instead of two and although a little loggy, the upgrade ran through without incident. After optimization, powered down and rebooted with two processors. At the sign on screen there was a kernel panic and it rebooted. I let it and after a little bit of spinning beach ball, it came up and seems to be functional. System info indicates 8gb ram and 2 cores as expected. No request for fix - just providing data for analysis. Thanks for your efforts!

[jimbolimbo13]

Thanks for sharing. I've been unable to upgrade from Big Sur to Monterey. It keeps ending in a kernel panic boot loop. Currently using 4 cores and 8gb ram. I'll try it with 1cpu and see if it works 🙏

Update: I wanted to leave my findings here for other folks to see in the spirit of the original post (CPU: 7th gen core i7, 4 core, 8 thread) Switching to 1cpu fixed the panic boot loop, and I successfully upgraded the VM to Monterey. Then tried going to 2cpu's, and that worked fine === EDIT: This worked initially but eventually panicked as well. I switched to 1cpu and it is stable again Going to 4 cpus led to same hard kernel panics and boot loops Tried 3 cpus for fun and it booted, then died shortly after login with a panic

I just use the machine to forward my iMessages and shared iCloud albums onto non-Apple computers, so I'm not too worried

[beriaanirudh]

Thanks for sharing this @enigma0456 @jimbolimbo13 . I upgraded to Monterey, it looped in boot, I reduced to 1 CPU and upgraded, which succeeded. Now, with 2 CPUs, kernel panics as soon as I open a terminal / Xcode. It works with 1 CPU, so I am not blocked, but its slow. Can you please share other VM configs that you are using? Specifically these are mine:

1. Motherboard: Base Memory 8192MB
2. Motherboard: Chipset: ICH9
3. Motherboard: Pointing Device USB Tablet
4. Motherboard: Enable I/O APIC (true)
5. Motherboard: Enable EFI (true)
6. Motherboard: Hardware Clock in UTC time (true)
7. Processor: Execution cap 100%
8. Processor: Enable PAE/NX (true)
9. Processor: Enable Nested VT-x/AMD-V (false)
10. Acceleration: Paravirtualization Interface Default
11. Acceleration: Enable Nested Paging (false)

Can you please point what config/s are different in your setup? PS: I am on Ubuntu 20.04 on AMD Ryzen 5

[enigma0456]

The only setting that is different is the last - I have nested paging enabled. Running Ubuntu 21.10 on HP Probook 4440s. I basically ran the script to create the Catalina machine with all the extra settings and have successfully upgraded through all the Big Sur iterations and then on into Monterey. Monterey has proven to be less stable. I have used VB for many years on Linux hosts running Windows VMs in production. I have always seen issues when you allocate more than one processor to the guest. so this doesn't surprised me. My thinking is that even though the guest has only one processor the host can use multiple cores to service the guest requests. I'm no expert in this so take it with a grain of salt. I have found that making a VB clone of the original machine and then using that as a base for fresh installs, upgrades, etc has been very useful. Make new UUIDs and Mac Addresses when you clone to avoid VB complaints about duplicates. Fun stuff courtesy of myspaghetti!!!

[jimbolimbo13]

@beriaanirudh I actually switched back to only 1 vCPU as 2 cpus turned out to be unstable after a while. That said, after spending some time with both configurations, it appears to perform better with only 1 cpu

[crslp]

The update to v12.3.1 Monterey only worked when using 1 cpu core. Runs stable, tho.

[nirit100]

Hey, Just in case this does not resolve the issue for some Windows users among you (in general i mean, not necessarily using this script), for me it worked when disabling the Windows Hypervisor: bcdedit /set hypervisorlaunchtype off Whether or not that is acceptable is up to you to decide.

Edit: Several typos, am tired