Files
home-network-k3s-impl/infra
jakman85 47f02c6e06 docs(prod): second independent confirmation + no cmdline workaround exists
A second research pass reached the same root cause by a different route and pinned the
arithmetic. Recording it because convergence from two independent lines is what turns this from
a good hypothesis into a settled diagnosis.

MECHANISM TO THE BYTE:
- the garbage 'version' node 2 read was 1463964749 = 0x5742544D = ASCII 'MTBW'. The kernel is
  reading unrelated data. HP publishes the MEMATTR pointer into memory /sys/firmware/memmap calls
  plain System RAM, so the pre-Linux boot chain overwrites it.
- tbl_size is a SIGNED int; num_entries * desc_size wraps mod 2^32 and goes NEGATIVE when bit 31
  lands. memblock_reserve sign-extends it and memblock_cap_size clamps to PHYS_ADDR_MAX - base,
  so EVERYTHING above 0xbeeb0018 is reserved.
- memblock_free_all then hands the allocator nothing above that line while present_pages (from
  memblock.memory) is untouched -> present 3340288 / managed 0.
- 'Failed to map EFI Memory Attributes table' is emitted LATER by efi_memattr_apply_permissions();
  it is positive PROOF the reservation already happened, a consequence rather than the cause.

CLEANEST A/B TELL, one dmesg line: NODE_DATA(0) on prod-2 ends at 0xbeeb0000 — pgdat forced
immediately BELOW the reservation — while on prod-1 it ends at 0x82f800000, the top of RAM.
Identical 0x2a980 allocation, opposite placement.

THERE IS NO KERNEL CMDLINE WORKAROUND. efi_memattr_init() is called from
efi_config_parse_tables(), and x86's efi_init() calls efi_config_init() BEFORE the
efi_runtime_disabled() bail-out — so noefi / efi=noruntime / efi=novamap do NOT prevent the
reservation. A fixed kernel is the only real fix.

EFI_MEMORY_SP / soft-reserved was the strongest competing theory and is EXCLUDED BY MEASUREMENT:
/sys/firmware/memmap/10/type reads 'System RAM'. Soft-reserved would print as 'Soft Reserved' and
is never memblock_add()ed, which would have left present at ~0 rather than 3340288.

Also records that the hardening landed exactly one release late for Debian 13 (bug present since
2016; 8fbe4c49c0cc first in v6.13; follow-up 5d0faa8e8369) and that a Debian BTS report against
src:linux is warranted — 6.12 is Debian 13's kernel for the release lifetime.

Serves: R-ENV-01, R-ENV-03. Task: T-7.1.
2026-09-01 22:16:22 -05:00
..

infra/ — node provisioning and the toolchain

OpenTofu (Proxmox VE) + cloud-init + Ansible bring up the 3-node k3s/Cilium dev cluster. Spec: ../home-network-k3s/docs/02-environments-and-provisioning.md.

Path What
tofu/ The "Create" stage: 3 cloud-init'd VMs on the Proxmox box (bpg/proxmox provider)
cloud-init/ First-boot baseline shipped as a Proxmox user-data snippet
ansible/ The "Baseline"/"Configure" stages: k3s HA, Cilium, kube-vip, the VPN egress gateway
devcontainer/ The pinned toolchain (tofu, ansible, sops, age, flux, kubectl, helm and the whole CI gate toolchain)
cluster.sh RETIRED — drove the old libvirt VMs; does not work against Proxmox
PHASE1-STATUS.md Current state of the cluster and how to reconnect to it
PHASE1-SCOPE.md Historical Phase-1 scoping doc (libvirt era — superseded)

Where the cluster actually lives

The dev cluster is not on this workstation. It runs on a Proxmox VE host; the nodes sit on the Proxmox LAN and are reached across a pfSense NAT:

Nodes k3s-dev-1/2/3 at 192.168.1.50/.51/.52 — 6 vCPU, 24 GiB, Debian 13, k3s v1.36.4
kube-API kube-vip VIP 192.168.1.49:6443, reached from the workstation via NAT 192.168.2.50:6443
Node SSH pfSense NAT 192.168.2.102:2250/2251/2252 → node :22 (Ansible only)
Ingress VIP 192.168.1.53 (Cilium L2, shared Gateway); .53–.60 reserved for LB VIPs

The earlier libvirt/KVM cluster on 10.73.0.0/24 is retired. Any doc or command referencing virsh, qemu:///system, or 10.73.0.x for the cluster is historical.