Adding some details about this issue. It looks like the real problem is the serial driver, in fact with a 5.4 kernel we can see the following in dmesg:
[ 4.991325] 0000:16:00.0: ttyS0 at MMIO 0xc5a00000 (irq = 85, base_baud = 115200) is a 16550A With the 5.8 kernel we don't see any message at all about ttyS0, meaning that the serial isn't properly recognized. A temporary workaround could be to remove console=ttyS0 from the kernel boot parameters, this would probably make cloud-init happy, but this is not obviously the right solution. I'll investigate more to find the exact commit that introduced this regression. Thanks Paride for helping me out to reproduce and test this problem! -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux-aws in Ubuntu. https://bugs.launchpad.net/bugs/1896604 Title: Groovy kernel (5.8.0-1004-aws) creates broken /dev/console on i3.metal instances Status in cloud-images: New Status in linux-aws package in Ubuntu: New Bug description: 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? To manage notifications about this bug go to: https://bugs.launchpad.net/cloud-images/+bug/1896604/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
