I have just done "emerge --sync" and "emerge -avuDN --with-bdeps y world" portage says that: "net-wireless/rfkill ("net-wireless/rfkill" is blocking sys-apps/util-linux-2.31)"
See bug https://bugs.gentoo.org/635158.
*** This bug has been marked as a duplicate of bug 635158 ***
No. It is not a duplicate of bug #635158. You probably had net-wireless/rfkill in world file, which prevented emerge from solving problem.
*** Bug 660968 has been marked as a duplicate of this bug. ***