Failed Mageia 5 install [SOLVED]

[hankivy]

My system was Mageia 5, LILO boot loader, with RAID1 for the root partition (/), and /boot, /home, /var, /tmp, etc.
I did the network upgrade using urpmi. It looked like it worked fine.
If I tried to boot the Mageia 6 kernel, I got "kernel and initrd memory conflict" as an error message.
If I booted an older Mageia 5 kernel the system came up ok.
I updated the boot as described above, selecting "GRUB2 with a graphical interface" as my boot loader.
Then I could boot both the older Mageia 5 kernel, and the Mageia 6 kernel ok.