2.6.23

[http://kernelnewbies.org/known_regressions_2623 regressions in 2.6.23]

2.6.22

[http://kernelnewbies.org/known_regressions_2622 regressions in 2.6.22]

2.6.21

[http://kernelnewbies.org/known_regressions_2621 regressions in 2.6.21 (unmaintained)]

Distro-tracked regressions

Gentoo

[http://bugs.gentoo.org/buglist.cgi?query_format=advanced&short_desc_type=allwordssubstr&short_desc=&long_desc_type=substring&long_desc=&bug_file_loc_type=allwordssubstr&bug_file_loc=&status_whiteboard_type=anywordssubstr&status_whiteboard=&keywords_type=allwords&keywords=&bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&bug_status=RESOLVED&resolution=UPSTREAM&resolution=---&emailassigned_to1=1&emailtype1=substring&email1=&emailassigned_to2=1&emailreporter2=1&emailcc2=1&emailtype2=substring&email2=&bugidtype=include&bug_id=&chfieldfrom=&chfieldto=Now&chfieldvalue=&cmdtype=doit&order=Reuse+same+sort+as+last+time&query_based_on=Kernel+regressions&field0-0-0=status_whiteboard&type0-0-0=regexp&value0-0-0=linux-2\.6\..*-regression Click here]

This list is kept relatively up-to-date. Gentoo kernels are only lightly patched, and the majority of bugs have been reproduced on unpatched kernels and reported upstream. Gentoo only track release kernels, not -rc releases (it's nice to see the scope of Adrian's previous work increased).