Comment 10 for bug 529363

I experience the exact same problem.
I have an old computer with an Abit KR7A Raid motherboard, which has an HPT372 controller (see http://file.abit.com.tw/pub/download/manual/english/kr7a-raid.zip)
It worked correctly for years under Ubuntu 8.04.
I did a fresh install of Ubuntu 10.04 (not an upgrade) and had the infinite reboot loop too.

A new fresh install of Ubuntu 8.04.3 from the liveCD works well.
The same reboots occur if I install from the liveCD or from the alternate CD.
If I boot on the liveCD, it works well and I can access the hard disk without any problem. I can see that nothing has been written in /var/log/dmesg or other log files : the reboot happens inside Grub2, before booting the OS.
I suppose that the reason why it works with ubuntu 8.04 is that it uses Grub, and not Grub2

My hard disk is an IDE one, plugged in the IDE3 port (the one controlled by the HPT372). If I plug it in IDE4 (also controlled by HPT372), and reinstall Ubuntu, I have the same behavior.
My IDE1 and IDE2 ports are used by CD/DVD drives and are slower than the HPT372 (U-DMA-133 vs U-DMA-100). I'll try to plug my hard disk on IDE1 or IDE2 (which are not controlled by HPT372), to check if the bug is related to this controller