From e0ab5f5af3f7d4743366368c09abf668ee78538a Mon Sep 17 00:00:00 2001
From: "Casper V. Kristensen" <casper@vkristensen.dk>
Date: Wed, 13 Nov 2024 02:50:39 +0100
Subject: [PATCH] tor: enable hot-adding memory

---
 hosts/tor/hardware.nix | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/hosts/tor/hardware.nix b/hosts/tor/hardware.nix
index 0a546a1..c3be88e 100644
--- a/hosts/tor/hardware.nix
+++ b/hosts/tor/hardware.nix
@@ -9,7 +9,7 @@
     (modulesPath + "/profiles/qemu-guest.nix")
   ];
 
-  boot.initrd.availableKernelModules = ["ata_piix" "uhci_hcd" "virtio_pci" "virtio_scsi" "sr_mod" "virtio_blk"];
+  boot.initrd.availableKernelModules = ["ata_piix" "uhci_hcd" "virtio_pci" "virtio_scsi" "sd_mod"];
   boot.initrd.kernelModules = ["dm-snapshot"];
   boot.kernelModules = [];
   boot.extraModulePackages = [];
@@ -37,5 +37,17 @@
     }
   ];
 
+  # Enable hot-adding memory
+  # https://pve.proxmox.com/wiki/Hotplug_(qemu_disk,nic,cpu,memory)
+  # Nix code inspired by (this isn't hyperv):
+  # https://github.com/NixOS/nixpkgs/blob/master/nixos/modules/virtualisation/hyperv-guest.nix
+  services.udev.packages = lib.singleton (pkgs.writeTextFile {
+    name = "proxmox-memory-hotadd-udev-rules";
+    destination = "/etc/udev/rules.d/80-hotplug-mem.rules";
+    text = ''
+      SUBSYSTEM=="memory", ACTION=="add", TEST=="state", ATTR{state}=="offline", ATTR{state}="online"
+    '';
+  });
+
   nixpkgs.hostPlatform = lib.mkDefault "x86_64-linux";
 }