Thanks for the report, I'm adding the relevant people to CC now. Please try to consult the MAINTAINERS file next time 'cause networking is a bit too big for the right people to always notice reports.
My best guess below.. On Fri, 9 Jan 2026 09:40:34 +0000 Wenger Jeremie (EDU) wrote: > Hello, > > I would like to report a regression in the e1000e driver affecting an Intel > integrated Ethernet controller. > > Hardware: > Intel Ethernet controller [8086:550a] > Driver: e1000e > > Summary: > - RX stops working after an Ethernet link down/up (unplug/replug cable). > - TX still works. A system suspend/resume reliably restores RX. > > Regression range: > - Working: v6.12.22 > - Broken: v6.12.43 .. v6.18.3 (tested on Debian 12 backports, Debian 13, > Debian sid). v6.18.3 is the most recent kernel tested so far, so the > regression is likely still present in newer kernels. Judging by the range seems like it has to be efaaf344bc2917cb Would you be able to try building a kernel with that commit reverted? Hi, Thanks for looking into this. Just to provide some additional context and help avoid duplicated work: the issue has also been discussed on [email protected], and I was pointed to a fix that landed in mainline. I tested the issue with Linux 6.19 (6.19~rc4-1~exp1), and the problem is fully resolved there: RX correctly recovers after a link down/up without requiring a suspend/resume cycle. This behavior change appears to be due to commit: 3c7bf5af2196087f394f9099b53e37569636b259 Given that current mainline works as expected, I did not attempt reverting efaaf344bc2917cb. I also asked on netdev whether a backport of the above fix to stable kernels would be appropriate. Please let me know if you still think a targeted revert test would be useful. Best regards, Jérémie > Symptoms: > - Link is detected (1Gbps, full duplex). > - DHCP DISCOVER frames are transmitted (confirmed via external packet > capture). > - No packets are received (no DHCP OFFER, RX appears dead). > - Booting with the cable plugged works. > - The issue is triggered only after unplugging and replugging the cable. > - A suspend/resume cycle restores RX immediately. > - Using a USB Ethernet adapter (r8152) on the same network works correctly. > > Reproduction steps: > - Boot with Ethernet cable plugged. > - Verify network connectivity works. > - Unplug the Ethernet cable. > - Plug the Ethernet cable back in. > - Observe that RX no longer works (no DHCP OFFER). > - Suspend/resume the system → RX works again. > > This suggests that the PHY or RX path is not correctly reinitialized on link > up after a link down event, while the resume path performs a more complete > reset. > > I can provide additional logs, ethtool statistics, or test patches if needed. > > > Best regards, > > Jérémie Wenger
