[Intel-wired-lan] [e1000e] Intel I219-LM host becomes unreachable under VM network load when AMT SOL/IDER is active

[Viktor Donner <vikdon@gmx.com>]

Hello,

I am reporting an issue involving the e1000e driver, Intel I219-LM,
network offload, and Intel AMT/ME remote-management state.

Environment:
- Host: Proxmox VE 9.2.4
- Kernel: 7.0.14-4-pve
- NIC: Intel I219-LM
- Driver: e1000e
- Driver version: 7.0.14-4-pve
- Firmware version: 0.4-4
- PCI address: 0000:00:1f.6
- Link: 1000 Mb/s, full duplex
- Host bridge: Linux bridge vmbr0
- Guest traffic: VirtIO VM network interface

Observed behavior:
When running a speed test inside a VM, at approximately 600+ Mbit/s
download traffic, the Proxmox host becomes completely unreachable over
the network:

- no ICMP response
- no SSH access
- no Proxmox web interface
- the physical/vPro console initially remains available
- a normal reboot may hang, requiring an AMT hardware reset/power cycle

The NIC still appears administratively UP and LOWER_UP, and the bridge
configuration and IP address remain present.

With TSO/GSO/GRO disabled using:

     ethtool -K eno1 tso off gso off gro off

the problem does not occur, but network performance decreases to
approximately 440/239 Mbit/s.

Relevant boot messages while MeshCommander / AMT remote management was
active:

     e1000e 0000:00:1f.6 (uninitialized): Reset blocked by ME
     e1000e 0000:00:1f.6: PHY reset is blocked due to SOL/IDER session.

After completely closing MeshCommander and rebooting, these messages
disappeared. TSO/GSO/GRO were enabled again, and repeated speed tests
did not reproduce the host lockup.

Current clean boot state:
- TSO: on
- GSO: on
- GRO: on
- tx_timeout_count: 0
- rx_errors: 0
- tx_errors: 0
- CRC errors: 0
- no failed systemd units

This suggests a possible interaction between e1000e recovery/reset,
Intel ME ownership of the I219-LM PHY, active AMT SOL/IDER sessions,
and high network load/offload processing.

Please advise:
1. Is this a known e1000e/I219-LM issue?
2. Is blocking PHY reset during SOL/IDER expected to prevent recovery
    from a TX/RX hang?
3. Are there recommended driver parameters or mitigations other than
    disabling TSO/GSO/GRO?
4. What additional traces or register dumps would be useful?

Hardware:
- Motherboard: Gigabyte Q370M D3H GSM PLUS rev. 1.0
- Primary NIC: Intel I219-LM
- Secondary NIC: Intel I211 using the igb driver, currently not cabled

Regards,
Viktor D
vikdon@gmx.com