On Tue, Apr 28, 2020 at 6:58 PM George Avrunin avrunin@math.umass.edu wrote:
Fedora 31, fully upgraded (I think...) Summary: twice in the last three days (since getting kernel 5.6.6, though I have no idea if that's related), this machine has hung completely after running "sudo dnf upgrade" while logged in over ssh. It becomes completely unresponsive to the network and to the keyboard, mouse, etc., I go to it to reboot. I've had to use the power button. The only strange things I see in the logs are long strings of null characters (that show as ^@) in the dnf.log when the dnf transactions crash the machine.
Andre Robatino posted a link to this bug awhile ago:
https://bugzilla.redhat.com/show_bug.cgi?id=1826091
That sounds like the symptoms you are seeing. It's a bug in the 5.6.6 kernel. It should be fixed in the 5.6.7 kernel, which will be available soon:
https://bodhi.fedoraproject.org/updates/FEDORA-2020-64c805f706