The cause is still unknown of why the interface is gone. Could you download and install the latest amd64/build generic deb files in https://kernel.ubuntu.com/~kernel-ppa/mainline/v5.13/ (see section "How do I install an upstream kernel?" in https://wiki.ubuntu.com/Kernel/MainlineBuilds) and check if the ethernet is still gone after resume?
And also try my v2 kernel in https://people.canonical.com/~mschiu77/lp1931301/v2/ which I add some debug messages to address when/where the ethernet interface gone. Please post full dmesg output for both kernels. Thanks -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1931301 Title: NIC unavailable after suspend to RAM To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1931301/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
