The latest kernel reliably soft locks on my T400 thinkpad. Sometimes it locks up before the elogind login prompt, sometimes it reaches the prompt but I can't log in. It does not reboot on ctrl-alt-del, although it does seem to send some kind of signal to elogind. It does reboot for alt-sysrq-b. When I got to see the kernel log, it looked like it was stuck in some BTRFS related code. I use BTRFS on an SSD on this machine. I know we have some other users with T400 Thinkpads, maybe they have run into it as well?
I will try upgrading again since the kernel is a few days old. $ guix system describe Generation 116 Oct 23 2022 03:52:27 file name: /var/guix/profiles/system-116-link canonical file name: /gnu/store/dhvng1gj6z88qzq6f2s1bw34jk668z5y-system label: GNU with Linux-Libre 5.19.16 bootloader: grub root device: label: "GUIX" kernel: /gnu/store/dzim8lv0wv9dk94f38a1ly35ckmfscm3-linux-libre-5.19.16/bzImage channels: guix: repository URL: https://git.savannah.gnu.org/git/guix.git branch: master commit: 78d4a08ac3a1de481bc56eef967a2e5ed2a912d5 raingloom: repository URL: https://git.sr.ht/~raingloom/guix-packages branch: master commit: bd30bbb2f7815e212d327a379ddbddc78fc4428a guix-science: repository URL: https://github.com/guix-science/guix-science.git branch: master commit: 2602edd5ec989d244ea065b2edfe3b95bf8a8c3d nonguix: repository URL: https://gitlab.com/nonguix/nonguix.git branch: master commit: 3f00d57adce5d0a185708fd5c7c5ff6f852c2bf7 configuration file: /gnu/store/mldk0f0lmnsc7ahv0hh4cpd7a0q17cmy-configuration.scm