Comment 1 for bug 1896604

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!