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Date: Fri, 17 Jan 1997 13:40:47 -0500 (EST)
From: Thomas David Rivers <ponds!rivers@dg-rtp.dg.com>
Message-Id: <199701171840.NAA09747@lakes.water.net>
To: ponds!freefall.cdrom.com!freebsd-hackers, ponds!eunet.ie!nick
Subject: Re: kern/2516: Filesystem trouble in 2.2-BETA_A
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> >Description:
> 
> 	One of the systems in here crashed this morning with an error:
> 
> 		blkfree: freeing free block
> 
> 	The partition affected was:
> 
> : Filesystem   1K-blocks     Used    Avail Capacity  Mounted on
> : /dev/sd1s1f     794783   488075   266969    65%    /var/spool/overview
> 
> : # dmesg | grep ahc3
> : ahc3 <Adaptec 3940 SCSI host adapter> rev 3 int a irq 5 on pci1:5
> : ahc3: aic7870 Wide Channel B, SCSI Id=7, 16 SCBs
> : ahc3 waiting for scsi devices to settle
> : (ahc3:1:0): "SEAGATE ST32550W 0021" type 0 fixed SCSI 2
> : sd1(ahc3:1:0): Direct-Access 2047MB (4194058 512 byte sectors)
> 
> 	I don't have the output from the printf statement immediately
> 	preceding this in /sys/ufs/ffs/ffs_alloc.c.
> 
> 	The firesystem was created with newfs (no special args) last Sunday
> 	(97/01/12) and the machine had been up since then without any
> 	trouble.


 Well - I'd have to say that this is exactly the type of 
panic I have experienced with 2.1.0, 2.1.5 and 2.1.5-STABLE.

 Interestingly enough, my recently installed 2.1.6.1  hasn't (yet)
experienced it.

 I've been trying to determine a consistent reproduction; if you
can accomplish this - I'm sure it would go a long way toward
fixing this problem.

 I've been working in ffs_alloc.c - it's not at all obvious to
me that the problem is there.  I'm not discounting it; but several
read-throughs of the code haven't found it. 

	- Dave Rivers -