I came across the problem after upgrading my system through
During the upgrade, I encountered a python package conflict which caused the upgrade transaction aborted. So I resolved the conflict: removing the python package by
pip uninstall pkg_name, then retried
pacman -Syu. This time no more errors.
Then I rebooted my system and the problem occurred:
Warning: /lib/modules/4.19.1-arch1-1-ARCH/modules.devname not found - ignoring starting version 239 /dev/nvme0n1p2: clean, 968023/31227904 files, 27066236/124895569 blocks mount: /new_root: unknown filesystem type 'ext4' You are now being dropped into an emergency shell, sh: can't access tty: job control turned off [rootfs] #
BTW: As the warning indicating, I was upgrading kernel 4.18 to 4.19