kern/60526: Post-PAE stable SMP machine freezes

[S?ren Schmidt]

Eugene Grosbein wrote:
> Hi!
> 
> According to
> http://freebsd.rambler.ru/bsdmail/freebsd-hackers_2003/msg03936.html
> the problem may be related to the <ServerWorks ROSB4 ATA33 controller>
> and ATA write cache (hw.ata.wc=1).
> 
> Note however, I had no kernel panic with post-PAE STABLE.
> I had kernel lockup. I can understand kernel panic due to the faulty
> devices but not endless loop that it seems to happen.
> 
> It's known (and noted in the Errata for 4.9-RELEASE)
> that PAE integration broke hw.ata.tags. Perhaps, its time
> either to document that hw.ata.wc is broken for noted controller too,
> either to forbid write cache for it by force.

I have a hard time beliving WC can be the problem. WC is a function of 
the disk drive it has nothing todo with the controller or even the way 
we talk to the disk...
That said, the ROSB4 is known to be wierd, bad things can easily happend 
with it in some setups and there is noting we can do about it in SW 
(less using PIO mode). However some HW vendors seem to have found a HW 
solution to the problem (ASUS is one of them, my old CUR-DLS doesn't 
show the problems at all)...

-- 
-S?ren