Do a more thorough job at scrubbing the install disk

So we don't fail on past installations of linux

builder/build-iso.sh

@@ -73,7 +73,7 @@ mkdir -p "$build_cache_dir/airootfs/opt/packages/"
 cp "/tmp/$NODE_FILENAME" "$build_cache_dir/airootfs/opt/packages/"
 
 # Add our additional packages to packages.x86_64
-arch_packages=(linux-t2 git gum jq openssl plymouth tzupdate omarchy-keyring)
+arch_packages=(linux-t2 git gum jq openssl plymouth tzupdate omarchy-keyring lvm2 cryptsetup parted)
 printf '%s\n' "${arch_packages[@]}" >>"$build_cache_dir/packages.x86_64"
 
 # Build list of all the packages needed for the offline mirror

configs/airootfs/root/.automated_script.sh

@@ -70,6 +70,61 @@ set_tokyo_night_colors() {
   fi
 }
 
+install_disk() {
+  jq -er 'first(.disk_config.device_modifications[]? | select(.wipe == true) | .device)' user_configuration.json
+}
+
+cleanup_install_disk() {
+  local disk="$1"
+
+  if [[ -z "$disk" || ! -b "$disk" ]]; then
+    echo "Could not determine install disk for cleanup" >&2
+    return 1
+  fi
+
+  echo "Cleaning up existing holders on install disk: $disk"
+
+  # Ensure that no mounts exist from past install attempts.
+  findmnt -R /mnt >/dev/null && umount -R /mnt || true
+
+  # Turn off swap and unmount anything backed by the selected disk, including
+  # device-mapper children from a previous install. Active LVM/swap holders can
+  # prevent the kernel from re-reading the partition table after archinstall
+  # wipes and recreates it.
+  while read -r dev; do
+    [[ -b "$dev" ]] || continue
+
+    swapoff "$dev" 2>/dev/null || true
+
+    while read -r target; do
+      [[ -n "$target" ]] || continue
+      umount "$target" 2>/dev/null || true
+    done < <(findmnt -rn -S "$dev" -o TARGET 2>/dev/null || true)
+  done < <(lsblk -rnpo PATH "$disk")
+
+  # Deactivate any LVM volume groups whose physical volumes live on the selected
+  # disk. This is the common case when replacing Fedora/Alma/RHEL installs.
+  while read -r dev type; do
+    [[ "$type" == "disk" || "$type" == "part" || "$type" == "crypt" ]] || continue
+
+    while read -r vg; do
+      [[ -n "$vg" ]] || continue
+      vgchange -an "$vg" 2>/dev/null || true
+    done < <(pvs --noheadings -o vg_name "$dev" 2>/dev/null | awk '{$1=$1; print}' | sort -u)
+  done < <(lsblk -rnpo PATH,TYPE "$disk")
+
+  # Close any LUKS mappings stacked on the selected disk after filesystems and
+  # swap have been released.
+  while read -r dev type; do
+    [[ "$type" == "crypt" ]] || continue
+    cryptsetup close "$dev" 2>/dev/null || true
+  done < <(lsblk -rnpo PATH,TYPE "$disk")
+
+  blockdev --flushbufs "$disk" 2>/dev/null || true
+  partprobe "$disk" 2>/dev/null || true
+  udevadm settle || true
+}
+
 install_base_system() {
   # Initialize and populate the keyring
   pacman-key --init
@@ -79,8 +134,7 @@ install_base_system() {
   # Sync the offline database so pacman can find packages
   pacman -Sy --noconfirm
 
-  # Ensure that no mounts exist from past install attempts
-  findmnt -R /mnt >/dev/null && umount -R /mnt
+  cleanup_install_disk "$(install_disk)"
 
   # Workarounds for archinstall 4.2 regressions under Python 3.14:
   # 1. sync_log_to_install_medium: `self.target / absolute_logfile` drops