This problem still exists in Ubuntu Focal Fossa (development branch) 20.04 with linux-image-5.4.0-21-generic. It also exists in linux-image- unsigned-5.6.2-050602-generic_5.6.2-050602.202004020822_amd64.deb
With linux-image-5.4.0-21-generic I didn't get any error messages after "insmod b44" in recovery mode. Also I normally booted linux- image-5.4.0-21-generic with mem=1G (limiting available memory to 1 GB) twice and also didn't get error messages after "sudo insmod b44". These symptoms are consistent with the hypothesis that swiotlb bounce buffers normally get allocated above 1 GB, causing a problem for b44 because the device can't do DMA above 1 GB and the driver can't handle this situation. That's the same problem discussed in this thread from 2011 https://groups.google.com/forum/#!topic/linux.kernel/GEx80ZCue1o Obviously limiting memory to 1 GB has an unacceptable performance penalty, but it's nice to have at least one way to get working Ethernet. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1821564 Title: b44 Ethernet driver null pointer during initialization To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1821564/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
