If you are asking with regards to official errata you can apply via freebsd-update(8), then no, there hasn't been any errata issued for this particular issue (See https://www.FreeBSD.org/security/notices.html).
hmmm, i have custom kernel and world rebuilded (/usr/bin/svnlite checkout https://svn.FreeBSD.org/base/releng/10.1/ /usr/src) which is +/- same as freebsd-update.
so it seems that l2arc will never works on 10.1 with pools with ashift=12. This is strange
Does anybody knows, if is this fixed in 10.2 releng? Or it's best to wait for 10.3?