files damaged on memory disk on Marvell Discovery 78100

[Matthias Reyelt]

Hi,

I have changed the mount options for the memory disks and they work fine now. 
I also got rid of regular crashes of the board :-)

Are there other caveats in the virtual cache area, things that should be 
avoided on the Marvell ARM?

Matthias 


Am Mittwoch 19 Mai 2010 12:29:52 schrieb Rafal Jaworowski:
> 
> On 2010-05-19, at 08:19, Matthias Reyelt wrote:
> 
> > I have observed a strange behaviour on the Marvell Discovery:
> > 
> > I have a memory disk for /etc and /opt:
> > /dev/md0 on /etc (ufs, local)
> > /dev/md1 on /opt (ufs, local)
> > 
> > When I copy files to that disk, which are larger than 0x1ffff (131071 
bytes), 
> > these files differ from the original. This occurs only when copying to md. 
> > 
> > Kernel is:
> > FreeBSD discovery1 8.0-STABLE FreeBSD 8.0-STABLE #0 r206836: Mon Apr 19 
> > 12:53:42 CEST 2010    
> > root at vbcspc12.bcs.brunel.local:/usr/obj/arm/root/ARM/8/sys/DB-78XXX  arm
> > 
> > I had a look into the damaged file and found some excerpts from files 
located 
> > in /etc (which is also in RAM):
> > ------------------------------------------------------------
> > passwd: compat
> > passwd_compat: nis
> > shells: files
> > -----------------------------------------------------------------
> > ...
> > -----------------------------------------------------------------
> > staff:*:20:
> > sshd:*:22:
> > smmsp:*:25:
> > mailnull:*:26:
> > guest:*:3-���
> > ------------------------------------------------------------------
> > 
> > Looks as if the CPU has problems accessing the RAM. I have already changed 
the 
> > RAM, so I don't think it's a hardware problem. 
> > 
> > Any idea?
> 
> 
> Try turning off clustering on the filesystem(s). There was least one known 
problem in this area leading to cache incoherency, see this thread for more 
details (and how-to): 
http://lists.freebsd.org/pipermail/freebsd-arm/2008-December/001423.html
> 
> Rafal
> 
> 



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Dr.-Ing. Matthias Reyelt
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