System lockups caused by USB external HDD

[Hans Petter Selasky]

On Monday 24 January 2011 10:00:53 CDP wrote:
> On 01/24/11 01:56, Daniel O'Connor wrote:
> > On 24/01/2011, at 9:10, CDP wrote:
> >> g_vfs_done():da0s2[WRITE(offset=xxxxxxxxxxxx, length=16384)]error = 5
> >> [several more lines similar to the above]
> >> panic: softdep_move_dependencies: need merge code
> >> cpuid = 0
> >> KDB: stack backtrace:
> >> #0 0x... at kdb_backtrace+0x5e
> >> #1 0x... at panic+0x182
> > 
> > It looks like the disk is dying, or the FS is corrupt (the former might
> > cause the later).
> > 
> > Can you run smartctl on the disk? Unfortunately a lot of enclosures
> > reject SMART commands so you might not be able to :(
> 
> I have attached the output of smartctl -d sat -a /dev/da0. I didn't yet
> run a SMART long test for the simple reason that the disk is going into
> sleep mode and interrupts it. Haven't bothered to keep it alive for a
> long test but I might just do that.
> 
> Although, I doubt it's a disk failure, since I do backups on it without
> problems by using FreeBSD 7.3, on the same space where FreeBSD 8.x
> fails. And I am talking about over 150GB of data in one run, while
> 8.2-RC2 crashes after 5-10GB. I have experienced disk failure in the
> past, on SATA, and a few read/write errors never caused a system lockup.
> 
> My feeling is that enough traffic on USB causes the problem, and that
> this problem is only present in the new USB stack.
> Unfortunately downgrading to 7.x is not an option because there are
> things that won't work on this notebook.

If you run a simple test like this:

dd if=/dev/da0 of=/dev/null bs=65536
dd if=/dev/da0 of=/dev/null bs=16384

Do you then see any errors?

Do you have a spare USB memory stick which you could run similar write tests 
on?

--HPS