Created attachment 185915 [details]
patch for /usr/src/sbin/swapon/swapon.c
From fstab, swapon/swapoff/swapctl can handle file-based swap using md, and partition-based swap with geli by appending .eli to the disk name in fstab, but it doesn't recognize the .eli suffix when applied to a md-based swap.
Attached is a patch to enable this use case.
Note: the same problem exists with the .bde suffix but as it seems to me that gbde is deprecated, I didn't bother writing the relevant code. It would probably follow a similar pattern.