** Description changed: + [Impact] + + Starting with kernel 5.8 the default nr_uarts has been changed from 4 to + 2 for amd64, but this seems to affect i3.metal instances in AWS, because + ttyS0 is now remapped to ttyS4 and this is breaking tools like cloud- + init (and probably something else). + + [Test case] + + # echo > /dev/console + bash: echo: write error: Input/output error + + [Fix] + + Setting nr_uarts=4 by default (via CONFIG_SERIAL_8250_RUNTIME_UARTS) + restores the previous behavior and writing to /dev/console works without + returning any error. + + [Regression potential] + + Minimal. Restores the old behavior used in 5.4 (that shouldn't have + changed in the first place). + + [Original bug report] + Hi, When running Groovy daily images on i3.metal instances a broken /dev/console is created. The char device appears to be writable but writing to it causes an Input/output error. This is breaking cloud-init, as it tries to log to /dev/console, and is likely to break other programs. On Focal: root@ip-172-31-24-163:~# ls -l /dev/console crw------- 1 root root 5, 1 Sep 21 16:07 /dev/console root@ip-172-31-24-163:~# echo x > /dev/console root@ip-172-31-24-163:~# On Groovy: root@ip-172-31-20-184:~# ls -l /dev/console crw--w---- 1 root tty 5, 1 Sep 21 16:03 /dev/console root@ip-172-31-20-184:~# echo x > /dev/console bash: echo: write error: Input/output error The Groovy kernel log has a [ 3.561696] fbcon: Taking over console line in it, which is not present in the Focal kernel log (5.4.0-1024-aws). Perhaps fbcon should be prevented from taking over console?
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1896604 Title: Groovy kernel (5.8.0-1004-aws) creates broken /dev/console on i3.metal instances To manage notifications about this bug go to: https://bugs.launchpad.net/cloud-images/+bug/1896604/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
