This is due to a defect in the All-mounts implementation causing ramfs type file system to be included implicitly, rather than explicitly excluded.
This is expected to be resolved in upcoming versions following the immediate next which are nearing release:
All-mounts logic includes 90+ file system exclusions; if unexpected file systems are backed up, gather the following outputs to investigate further:
Linux
df -aTh > `hostname`_df_aTh.out 2>&1
mount > `hostname`_mount.out 2>&1
cat /etc/mtab > `hostname`_mtab.out 2>&1
AIX
mount > `hostname`_mount.out 2>&1
df -g > `hostname`_df.out 2>&1
lsfs > `hostname`_lsfs.out 2>&1
Solaris or HP-UX
df > `hostname`_df.out 2>&1
mount > `hostname`_mount.out 2>&1