Also Ubuntu 18.04.1 LTS here.
I tracked down the issue to the plymouth-theme-kubuntu-text.postinst
script:
Comparing /var/lib/dpkg/info/plymouth-theme-ubuntu-text.postinst and
/var/lib/dpkg/info/plymouth-theme-kubuntu-text.postinst we see that the
first has:
-
It's been a couple of months but I finally got around to revisit this
bug.
I had this happen reliably on 2 laptops, both updated from previous
versions of Ubuntu.
On one of these "plymouthd" really seemed to be the culprit (see my own
comment #22 ). I found out that the memory mapped region was a
Eduard,
you are correct, I added some debug output to the kernel itself (in
fs/file_table.c) to log the inode number that causes sys_mount to return
EBUSY.
The inode in my case was reported as 5669195 which according to the lsof
log is exactly the mapping you suspected:
plymouthd 31010
