Comment 1 for bug 1096307

Please elaborate on what you mean when you say "mount a non-existing device node". Do you mean you've added an entry to /etc/fstab? If so, please show the exact fstab that triggers this issue.

A missing system filesystem caused by an incorrect entry in /etc/fstab, or a failed disk, is indistinguishable from a device being slow to appear. It is therefore incorrect for mountall to silently ignore a missing disk and boot without it, as this would cause services to fail to start correctly; the only correct course of action is to halt the boot, notify the user of the missing filesystem, and give them the option to intervene. This is exactly what mountall does, presenting users via plymouth with the option to skip the disk.

So from your description, I don't think there's a bug here at all.