It seems libata was broken in 2.6.24 for pegasos. Take a look at https://bugzilla.redhat.com/show_bug.cgi?id=430802 for more informations and for the fix (http://patchwork.ozlabs.org/linuxppc/patchcontent?id=16281) Reproducible: Always Steps to Reproduce:
The commit for the patch referenced in comment #1 is located here: http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=092ca5bd61da6344f3b249754b337f2d48dfe08d This is included in vanilla-sources-2.6.25_rc2. I was able to patch gentoo-sources-2.6.24-r2 and compile it. Can you patch your own gentoo-sources-2.6.24-r2 and test the fix. Upon a successful test we can backport into the next release of gentoo-sources for the 2.6.24 kernel.
Fixed in genpatches-2.6.24-4 (gentoo-sources-2.6.24-r3), thanks for bringing this to our attention