panic: ffs_blkfree: freeing free block

[Don Bowman]

From: Tim Robbins [mailto:tjr at freebsd.org]
> 
> On Fri, Mar 05, 2004 at 12:31:51AM -0500, Don Bowman wrote:
> 
> > periodically (once a day or so), i'm getting a panic
> > as 'panic: ffs_blkfree: freeing free block'. 
> [...]
> > Suggestions on what I should look for or try?
> 
> Dropping to single user mode & forcing a fsck (with the -f 
> option) should
> fix this. It's a symptom of some kind of filesystem inconsistency
> that soft updates isn't expecting, and that background fsck 
> isn't trying
> to detect or repair.
> 

Each time i do that, the problem comes back shortly afterwards.
I know its not bad hardware, the disks all check out ok, its
a U320 scsi raid, disks do auto bad block sparing, scsi has all
kinds of crc and checksum. 

Is anyone else using ASR on current? Are you using it with a large
filesystem like this (~400GB)?