Hi, I'm seeing a regression on an HP ZBook using the e1000e driver (chipset PCI ID: [8086:57a0]) -- the system can't get an IP address after hot-plugging an Ethernet cable. In this case, the Ethernet cable was unplugged at boot. The network interface eno1 was present but stuck in the DHCP process. Using tcpdump, only TX packets were visible and never got any RX -- indicating a possible packet loss or link-layer issue.
This is on the vanilla Linux 6.16-rc4 (commit 62f224733431dbd564c4fe800d4b67a0cf92ed10). Bisect says it's this commit: commit efaaf344bc2917cbfa5997633bc18a05d3aed27f Author: Vitaly Lifshits <[email protected]> Date: Thu Mar 13 16:05:56 2025 +0200 e1000e: change k1 configuration on MTP and later platforms Starting from Meteor Lake, the Kumeran interface between the integrated MAC and the I219 PHY works at a different frequency. This causes sporadic MDI errors when accessing the PHY, and in rare circumstances could lead to packet corruption. To overcome this, introduce minor changes to the Kumeran idle state (K1) parameters during device initialization. Hardware reset reverts this configuration, therefore it needs to be applied in a few places. Fixes: cc23f4f0b6b9 ("e1000e: Add support for Meteor Lake") Signed-off-by: Vitaly Lifshits <[email protected]> Tested-by: Avigail Dahan <[email protected]> Signed-off-by: Tony Nguyen <[email protected]> drivers/net/ethernet/intel/e1000e/defines.h | 3 +++ drivers/net/ethernet/intel/e1000e/ich8lan.c | 80 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++----- drivers/net/ethernet/intel/e1000e/ich8lan.h | 4 ++++ 3 files changed, 82 insertions(+), 5 deletions(-) Reverting this patch resolves the issue. Based on the symptoms and the bisect result, this issue might be similar to https://lore.kernel.org/intel-wired-lan/[email protected]/ Affected machine is: HP ZBook X G1i 16 inch Mobile Workstation PC, BIOS 01.02.03 05/27/2025 (see end of message for dmesg from boot) CPU model name: Intel(R) Core(TM) Ultra 7 265H (Arrow Lake) ethtool output: driver: e1000e version: 6.16.0-061600rc4-generic firmware-version: 0.1-4 expansion-rom-version: bus-info: 0000:00:1f.6 supports-statistics: yes supports-test: yes supports-eeprom-access: yes supports-register-dump: yes supports-priv-flags: yes lspci output: 0:1f.6 Ethernet controller [0200]: Intel Corporation Device [8086:57a0] DeviceName: Onboard Ethernet Subsystem: Hewlett-Packard Company Device [103c:8e1d] Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+ Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 0 Interrupt: pin D routed to IRQ 162 IOMMU group: 17 Region 0: Memory at 92280000 (32-bit, non-prefetchable) [size=128K] Capabilities: [c8] Power Management version 3 Flags: PMEClk- DSI+ D1- D2- AuxCurrent=0mA PME(D0+,D1-,D2-,D3hot+,D3cold+) Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=1 PME- Capabilities: [d0] MSI: Enable+ Count=1/1 Maskable- 64bit+ Address: 00000000fee00798 Data: 0000 Kernel driver in use: e1000e Kernel modules: e1000e The relevant dmesg: <<<cable disconnected>>> [ 0.927394] e1000e: Intel(R) PRO/1000 Network Driver [ 0.927398] e1000e: Copyright(c) 1999 - 2015 Intel Corporation. [ 0.927933] e1000e 0000:00:1f.6: enabling device (0000 -> 0002) [ 0.928249] e1000e 0000:00:1f.6: Interrupt Throttling Rate (ints/sec) set to dynamic conservative mode [ 1.155716] e1000e 0000:00:1f.6 0000:00:1f.6 (uninitialized): registered PHC clock [ 1.220694] e1000e 0000:00:1f.6 eth0: (PCI Express:2.5GT/s:Width x1) 24:fb:e3:bf:28:c6 [ 1.220721] e1000e 0000:00:1f.6 eth0: Intel(R) PRO/1000 Network Connection [ 1.220903] e1000e 0000:00:1f.6 eth0: MAC: 16, PHY: 12, PBA No: FFFFFF-0FF [ 1.222632] e1000e 0000:00:1f.6 eno1: renamed from eth0 <<<cable connected>>> [ 153.932626] e1000e 0000:00:1f.6 eno1: NIC Link is Up 1000 Mbps Half Duplex, Flow Control: None [ 153.934527] e1000e 0000:00:1f.6 eno1: NIC Link is Down [ 157.622238] e1000e 0000:00:1f.6 eno1: NIC Link is Up 1000 Mbps Full Duplex, Flow Control: None No error message seen after hot-plugging the Ethernet cable. -- Best Regards, En-Wei.
