I experience the exactly same problem on my Fujitsu S6420 notebook which running Lucid 10.04 amd64 beta2 with the same SD host controller: O2 Mirco.
Then I tried booting my notebook using the latest Ubuntu Lucid 10.04 RC AMD64 LiveCD also. The same problem happened which is seen in the log files: dmesg, messages and syslog
I experience the exactly same problem on my Fujitsu S6420 notebook which running Lucid 10.04 amd64 beta2 with the same SD host controller: O2 Mirco.
Then I tried booting my notebook using the latest Ubuntu Lucid 10.04 RC AMD64 LiveCD also. The same problem happened which is seen in the log files: dmesg, messages and syslog