/tmp on mfs is blocked

misc@,

I just encountered wired case when my /tmp was blocked, and nothing had
worked.

via ps I saw:

root 59095 0.0 1.1 1049488 174152 ?? D Wed10PM 0:40.02 /sbin/mount_mfs -o rw -o nodev -o nosuid -s 1024m swap /tmp

and fstat -p 59095 points nothing abnormal:

USER CMD PID FD MOUNT INUM MODE R/W SZ|DV
root mount_mfs 59095 text / 53639 -r-xr-xr-x r 240160
root mount_mfs 59095 wd / 2 drwxr-xr-x r 512

htop reports that some swap was used and df points that ~200mb were used and
/tmp had plenty of free space.

Have you seen that before? How can I dig it future?

--
wbr, Kirill