Magic Trackpad 2 causes kernel heap corruption when passed to a Proxmox guest, GPFs

In mid-December I rebooted to upgrade my Proxmox kernel to pve-kernel-5.4.78-2-pve, but I immediately started having an issue where the kernel would trigger a GPF (general protection fault) and reset about 5-20 minutes after starting my macOS VM. I suspected that the new kernel was at fault, but I rolled back to the previous kernel and the problem persisted. I hadn’t experienced this fault before so I was a bit baffled about what change I made before that reboot could have triggered it.

To track down the issue, I built a version of Proxmox’s kernel with KASAN enabled. KASAN is the Kernel Address Sanitiser, it can detect kernel bugs like double-frees or out-of-bounds reads and writes by instrumenting the kernel to add checks around every memory access. This adds a bunch of CPU and memory space overhead, but the impact is bearable so long as your guest doesn’t need much service from the host kernel.

Continue reading Magic Trackpad 2 causes kernel heap corruption when passed to a Proxmox guest, GPFs

Running Tails as a VM with persistence on Proxmox

In this guide I’ll explain how you can run Tails as a VM in Proxmox while retaining the persistence feature, and keeping support for Proxmox backups and snapshots.

Firstly, note that running Tails as a VM defeats a lot of the security features it offers, since you now need to trust the hypervisor to be secure. The VM’s memory could be swapped to disk in the host’s swapfile or persisted in a guest snapshot (if the “include RAM” option is ticked), which will leak the contents of the guest onto the host’s persistent storage, including secret encryption key material.

Continue reading Running Tails as a VM with persistence on Proxmox

Working around the AMD GPU Reset bug on Proxmox using vendor-reset

Most modern AMD GPUs suffer from the AMD Reset Bug: The card cannot be reset properly, so it can only be used once per host power-on. The second time the card is tried to be used Linux will attempt to reset it and fail, causing the VM launch to fail, or the guest, host or both to hang.

gnif’s new vendor-reset project is an attempt to work around this AMD reset issue by replacing AMD’s missing FLR support with vendor-specific reset quirks.

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Installing macOS 11 “Big Sur” on Proxmox 6

This tutorial for installing macOS Big Sur Final using OpenCore has been adapted for Proxmox from Kholia’s OSX-KVM project and Leoyzen’s OpenCore configuration for KVM. You can get the full sourcecode on my GitHub here.

Requirements

I’ll assume you already have Proxmox 6 installed. You also need a real Mac available in order to fetch the OSK key.

Your Proxmox host computer’s CPU must support SSE 4.2, so for Intel your CPU must be at least as new as Nehalem, which was the first CPU generation to bear the “Core” i5/i7 branding. Older CPUs will cause the finder to repeatedly crash after installation completes (with an Illegal Instruction exception in the graphics code).

Modern AMD CPUs also support SSE 4.2 and will work with this guide.

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Installing macOS Catalina 10.15 on Proxmox 6.1 or 6.2 using OpenCore

macOS 11 Big Sur has now been released! If you’d like that version instead then please use my new Big Sur installation guide!

This tutorial for installing macOS Catalina using OpenCore has been adapted for Proxmox from Kholia’s OSX-KVM project and Leoyzen’s OpenCore configuration for KVM. You can get the full sourcecode on my GitHub here.

If you’d like to use Clover instead, use my older tutorial, but OpenCore works better!

Requirements

I’ll assume you already have Proxmox 6.1 or 6.2 installed. You also need a real Mac available in order to fetch the OSK key.

Your Proxmox host computer’s CPU must support SSE 4.2, so for Intel your CPU must be at least as new as Nehalem, which was the first CPU generation to bear the “Core” i5/i7 branding. Older CPUs will cause the finder to repeatedly crash after installation completes (with an Illegal Instruction exception in the graphics code).

Modern AMD CPUs also support SSE 4.2 and will work with this guide.

Continue reading Installing macOS Catalina 10.15 on Proxmox 6.1 or 6.2 using OpenCore

My macOS Big Sur / Proxmox setup

I thought it might be helpful for people following my guide for installing macOS Big Sur on Proxmox if I described my setup and how I’m using macOS.

Proxmox hardware specs

  • Motherboard: Asrock EP2C602
  • RAM: 64GB
  • CPU: 2 x Intel E5-2670 for a total of 16 cores / 32 threads
  • Storage
    • ASUS Hyper M.2 X16 PCIe 4.0 X4 Expansion Card
      • Samsung 970 Evo 1TB NVMe SSD for macOS
      • Samsung 950 Pro 512GB NVMe SSD
    • 38TB of spinning disks in various ZFS configurations
    • 1TB SATA SSD for Proxmox’s root device
  • Graphics
    • EVGA GeForce GTX 1060 6GB
    • AMD Radeon R9 280X (HD 7970 / Tahiti XTL) (not currently installed)
    • AMD Sapphire Radeon RX 580 Pulse 8GB (11265-05-20G)
  • IO
    • 2x onboard Intel C600 USB 2 controllers
    • Inateck USB 3 PCIe card (Fresco Logic FL1100 chipset)
    • 2x onboard Intel 82574L gigabit network ports
  • Case
    • Lian Li PC-X2000F full tower (sadly, long discontinued!)
    • Lian Li EX-H35 HDD Hot Swap Module (to add 3 x 3.5″ drive bays into 3 of the 4 x 5.25″ drive mounts), with Lian Li BZ-503B filter door, and Lian Li BP3SATA hot swap backplane. Note that because of the sideways-mounted 5.25″ design on this case, the door will fit flush with the left side of the case, while the unfiltered exhaust fan sits some 5-10mm proud of the right side of the case.
  • CPU cooler
    • 2 x Noctua NH-U14S coolers
  • Power
    • EVGA SuperNOVA 750 G2 750W

My Proxmox machine is my desktop computer, so I pass most of this hardware straight through to the macOS Big Sur VM that I use as my daily-driver machine. I pass through both USB 2 controllers, the USB 3 controller, an NVMe SSD, and one of the gigabit network ports, plus the RX 580 graphics card.

Continue reading My macOS Big Sur / Proxmox setup

Installing macOS Mojave 10.14 on Proxmox 5.4

With the release of macOS Catalina 10.15, this tutorial is now obsolete! Please check out the new Catalina tutorial here.

This tutorial for installing macOS Mojave has been adapted for Proxmox 5.4 from Kholia’s GitHub project for installing into vanilla KVM. There is more documentation there which will help out with enabling extra features and diagnosing problems!

Requirements

I’ll assume you already have Proxmox 5.4 installed. You also need a real Mac available in order to fetch the OSK key.

Your Proxmox host computer’s CPU must support SSE 4.2, so for Intel your CPU must be at least as new as Nehalem, which was the first CPU generation to bear the “Core” i5/i7 branding. Older CPUs will cause the finder to repeatedly crash after installation completes (with an Illegal Instruction exception in the graphics code).

Apparently modern AMD CPUs also support SSE 4.2 and can be used with this guide without any modification (maybe Bulldozer and certainly Ryzen), but I haven’t tested this myself.

Continue reading Installing macOS Mojave 10.14 on Proxmox 5.4

Patch OVMF to support macOS in Proxmox 5 and 6

Proxmox 5 and 6’s version of the OVMF firmware includes two commits (2ac1730 and 147fd35) that are intended to mark the pagetables as read-only during startup. This was first seen in Proxmox 5.1. This conflicts with the OsxAptioFixDrv drivers in Clover, which expect to be able to modify the pagetables to remap memory:

https://sourceforge.net/p/cloverefiboot/tickets/439/

I’ve patched OVMF to revert the effect of these two commits, which allows macOS to boot again (I also tested it by booting Windows 10, which worked fine). If you just want to download the fixed .deb, skip to the end of the article, otherwise if you want to build it yourself, follow along with the instructions in the next section:

Continue reading Patch OVMF to support macOS in Proxmox 5 and 6

Installing macOS High Sierra on Proxmox 5

With the final release of Mojave, this tutorial is now out of date, see the new tutorial for installing Mojave instead!

This tutorial for installing macOS Sierra has been adapted for Proxmox 5 from Kholia’s GitHub project for installing into vanilla KVM. There is more documentation there which will help out with enabling extra features and diagnosing problems!

Requirements

I’ll assume you already have Proxmox 5.1 installed. You also need a real Mac available in order to download High Sierra from the App Store and build the installation ISO. Your Proxmox host computer must have an Intel CPU at least as new as Penryn (I believe you would need a a custom Mac kernel in order to use an AMD CPU). Continue reading Installing macOS High Sierra on Proxmox 5

Passthrough of advanced CPU features for macOS [High] Sierra guests

When emulating macOS on Proxmox, it seems that we are forced to set the guest’s CPU type to “Penryn”. This is a very old architecture, and is missing some features that could unlock higher CPU performance. In particular, I wanted to use AVX (for accelerated stream processing) and AES-NI (for encryption), but macOS panics on boot if I set the CPU to Sandy Bridge, which would match my CPU which includes those features.

Luckily, kholia over at the OSX-KVM project has discovered that we can keep using Penryn, but enable the passthrough of individual advanced CPU features and have Sierra use them, even though Penryn never supported these features.

Continue reading Passthrough of advanced CPU features for macOS [High] Sierra guests