"ZFS: zfs_alloc()/zfs_free() mismatch" Problem with 8.2 Stable

[Zlatko Asenov]

Hello everyone,

I had set up a raidz2 ZFS on ROOT system with 4 SATA disks. Every disk 
had 64k freebsd-boot, 30G freebsd-zfs and freebsd-ufs for the rest 
space. I did it with the gpart utility.

One of the disks failed and I offlined the faulty 30G partition from the 
pool. The system worked with "no known data errors". After reboot I saw 
this message:

"ZFS: zfs_alloc()/zfs_free() mismatch"

and the system goes no further.

I booted with FreeBSD 9.0-RELEASE usb stick, imported the pool which did 
scrub by himself somehow. After the scrubbing finished all seemed ok, 
but after reboot I see the message again.

The system was FreeBSD 8.2-STABLE AMD64 with 4GB RAM.

Interesting to note is that this is my second issue with a faulted disk. 
However if I replace healthy HDD for upgrading purposes, everything 
passes fluently.

I pulled the data from /usr/home/  however part of it was damaged.

I also posted about the issue here:

http://forums.freebsd.org/showthread.php?t=31215

What can I do to prevent such a malfunction in future?


Best Regards!

Zlatko Asenov