I think the answer here is to stop passing "console=ttyS0". This is something that is typically only done for debugging.
dmesg shows a 14 second delay between the "console [tty1] enabled" and "console [ttyS0] enabled" messages. I suspect that because console=ttyS0 is passed the kernel is going to dump all the messages accumulated in dmesg so far to the serial port when it is registered as a console device. Because this is a slow device this consumes significant time, and it happens in an initcall so it blocks boot progress. Then boot from that point on is slowed down by printing messages out on the serial port every time something is printed to the kernel log. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1879290 Title: pc: no message on the screen for ~30s on fast HW Status in linux package in Ubuntu: Incomplete Status in snapd package in Ubuntu: New Bug description: The boot on real HW (ARock B450, Ryzen, NVME 240Gb) takes a long time without any visible feedback. Video: https://photos.app.goo.gl/RmaLviXNorjeh5BP7 With grub debug: https://photos.app.goo.gl/PJuXdxp8uedr7fWp9 (google photos has degraded quality quite a bit, may upload the originals if too bad) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1879290/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : firstname.lastname@example.org Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp