Bug#852194: make a /run/initramfs/messages

[Dan Jacobson <jidanni@jidanni.org>]

Package: initramfs-tools
Version: 0.126
Severity: wishlist

You generate
/run/initramfs/fsck-root
/run/initramfs/fsck.log
Good.

Please also generate a similar log of the messages that the user sees
fly by upon boot before the ones that are captured by journalctl.

Actually it turns out they are not messages before boot,
but messages during boot that don't have [ timestamps ] on them.
There are not logged anywhere, and fly off the screen.

E.g., I saw one, something about "Failed to start ..." that was just
outside of what I could pull back down with Shift-PageUp. Below it,
still thankfully on the screen was a message that told me to do
"systemctl status systemd-modules-load.service".
Again, both messages were not in journalctl.

(One would think changing log_buf_len boot parameter would give more
lines, but it doesn't.)