#!/bin/bash
###############################################################################
# fix-e1000e-offload.sh — Disable offload on e1000e NICs to prevent hangs
#
# The Intel e1000e driver has a known bug where TSO/GSO/GRO offload causes
# "hardware unit hang" resets on certain Intel NICs (I217-LM, I219-LM, 82571EB).
# This script disables offload features on all e1000e interfaces and installs
# a systemd service to persist across reboots.
#
# References:
#   https://forum.proxmox.com/threads/e1000-driver-hang.58284/
#   https://serverfault.com/questions/616485
#
# Run on each Proxmox host:
#   PROX_HOST=pfv-tsys4 bash tests/remote.sh prox-file proxmox/perf/scripts/fix-e1000e-offload.sh
###############################################################################
set -euo pipefail

echo "=== e1000e Offload Fix on $(hostname) ==="

# Find all e1000e physical NICs (skip bridges, bonds, virtual interfaces)
AFFECTED_NICS=()
for nic_path in /sys/class/net/*; do
    nic=$(basename "$nic_path")
    [ "$nic" = "lo" ] && continue
    # Skip bridges, bonds, virtual interfaces
    [ -d "${nic_path}/bridge" ] && continue
    [ -d "${nic_path}/bonding" ] && continue
    case "$nic" in
        tap*|veth*|fwpr*|fwln*|vmbr*|datanet*|storagenet*|tailscale*) continue ;;
    esac

    driver=$(ethtool -i "$nic" 2>/dev/null | awk '/^driver:/{print $2}')
    if [ "$driver" = "e1000e" ]; then
        AFFECTED_NICS+=("$nic")
        echo "  Found e1000e NIC: $nic"
    fi
done

if [ "${#AFFECTED_NICS[@]}" -eq 0 ]; then
    echo "  No e1000e NICs found. Nothing to do."
    exit 0
fi

# Apply fix live
echo ""
echo "--- Disabling offload features ---"
for nic in "${AFFECTED_NICS[@]}"; do
    echo "  $nic:"
    ethtool -K "$nic" tso off gro off gso off tx off rx off 2>&1 | sed 's/^/    /' || true
    tso_state=$(ethtool -k "$nic" 2>/dev/null | awk '/tcp-segmentation-offload/{print $2}' | head -1)
    echo "    tso=$tso_state"
done

# Install systemd service for persistence
echo ""
echo "--- Installing systemd service ---"
{
    echo "[Unit]"
    echo "Description=Disable offload on e1000e NICs (prevent hardware unit hang)"
    echo "After=network.target"
    echo "Wants=network.target"
    echo ""
    echo "[Service]"
    echo "Type=oneshot"
    echo "RemainAfterExit=yes"
    for nic in "${AFFECTED_NICS[@]}"; do
        echo "ExecStart=/sbin/ethtool -K $nic tso off gro off gso off tx off rx off"
    done
    echo ""
    echo "[Install]"
    echo "WantedBy=multi-user.target"
} > /etc/systemd/system/fix-e1000e-offload.service

systemctl daemon-reload
systemctl enable fix-e1000e-offload.service
echo "  Service installed and enabled (fix-e1000e-offload.service)"
echo ""
echo "=== Done. Affected NICs: ${AFFECTED_NICS[*]} ==="