Core 0 on 3D V-Cache CCD

Operating Systems & Open Source Linux
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Specs: Asus ProArt X670E-Creator WiFi, Ryzen 9 7950X3D, 64GB RAM (2x32), Proxmox 8.1.10

I’m making a gaming VM with vCPUs pinned to CPU cores located on 3D V-Cache CCD0, with the help the tutorial and a hookscript on proxmox forum:
[TUTORIAL] Hey Proxmox & Community - Let’s talk about resources isolation

The tutorial describes using CCD1 cores for a VM. The part of a script is to make all CCD1 cores offline to move all host threads to CCD0, “pin” them there and bring back online fresh, non-busy CCD1 cores and pin vCPUs to them.

In my case, I need to pin vCPUs to 3d cached CCD0 cores. The problem is, I can’t make Core 0 (which is located on CCD0) offline because it’s reserved by the kernel if I understand correctly.

Is there a way to make the kernel to reserve another CPU core/CCD/NUMA node? Maybe with BIOS settings or kernel parameters?

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I’d be starting here. https://docs.kernel.org/admin-guide/kernel-parameters.html, then pivot to searching the rest of the Documentation folder of the kernel.

Can you pin the cores without isolating them? I do this on my 5950x, and it works fine.