# ZFS: zfs_alloc()/zfs_free mismatch



## teisho (Dec 25, 2021)

Hi,
I've tried to upgrade my FreeBSD 12.2-RELEASE to 13.0-RELEASE and after the last reboot the System isn't booting anymore.
Any Ideas how to fix that?


----------



## covacat (Dec 25, 2021)

boot from external media and update bootcode


----------



## teisho (Dec 25, 2021)

I fixed it by rewriting bootcode to the disk with a rescue system.


----------

