Comment 9 for bug 86234

Replacing the UUID in the fstab with the "real" devicename á la /dev/sda2 fixes this problem for me, too.

The swapon command is called twice during the boot process. Once in checkroot.sh and once in mountall.sh, the latter because:

        # Execute swapon command again, in case we want to swap to
        # a file on a now mounted filesystem.

This shouldn't be a problem, because swapon -a normally ignores partitions that are already activated.

The following is my speculation: I think for some reason the /dev/mapper-devices aren't present at the time of the first swapon, so the regular device belonging to the UUID get's activated. When swapon gets executed the second time, the /dev/mapper-device is present and is going to be used, when the translation UUID->device is performed. As the /dev/mapper-device isn't in the swap -list yet, it's going to get activated although the underlying partition is already running under a different name.