I don't think this is a recent regression. I have seen the symptoms for a while and have only gotten around to investigating it yesterday. Also see the linked bug which describes exactly this issue and which was raised in 2009.
However, I am inclined to believe that this is more a glibc rather than a kernel bug. In particular this is likely somewhere in libnss_dns.so, the DNS plugin to the NSS system.
I don't think this is a recent regression. I have seen the symptoms for a while and have only gotten around to investigating it yesterday. Also see the linked bug which describes exactly this issue and which was raised in 2009.
However, I am inclined to believe that this is more a glibc rather than a kernel bug. In particular this is likely somewhere in libnss_dns.so, the DNS plugin to the NSS system.