i've suggested using my contrib/sd to a few people who are having trouble with sd devices. unfortunately, it's hard to apply patches without a working system. so as an experiment i built a cd that differs from the cd on sources only in the kernel and 9load and plan9.ini used. everything else is the same. (so if you rebuild the kernel, you'll get a different kernel; you'll need to apply paches yourself.)
as a further experiment, 9load has been modified so that it should Just Work from any supported sd boot device. 9load actually knows the device it booted from. "bootdev" stands in for the boot device. as in bootdev!cdboot!9pcflop.gz if this doesn't work for anybody, i'll remove it. and in any event, this an experiment, not a solution. ftp://ftp.quanstro.net/other/9atom.iso.bz2 one with (very noisy) ata probe debugging turned on is at ftp://ftp.quanstro.net/other/9atomdbg.iso.bz2 - erik