>>> I boot off a USB memory key, then use the sysctl init.root knob to
>>> chroot from a memory disk to a cgd0a on wd0a.
>> Grasping at more straws -- is the USB key formatted as FAT or FFS?
> ffs.  I was worried about FAT potentially causing permission problem,
> ironically. :)

I'm wondering if this might have something to do with the permissions
on the *real* root, the one that's normally inaccessible because
everything is chrooted below it.  The symptoms look a little like "it's
fine as long as $THING is in the cache"...I wonder if perhaps the
permissions on the chroot-to mount point in the USB-key root are
relevant.  Can you maybe mount the USB key elsewhere and see what the
ownership and mode bits on the root and mount point (and everything
leading to the mount point, if it's not directly under /) are?

More stabs in the dark, but at this point that seems to be about all
anyone has. :-/  Except you, who may be able to do something useful
with ddb.

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