Solaris stability and upgrades (was RE: [SunRescue] help a guy run2.6 on his 670MP)

[Loomis, Rip]

Both Jon and Dave are correct--I didn't clearly
state the underlying issue.

I suppose the way it *really* ought to be stated
on thisoldsun or wherever (in the "picking which
older sun to use and when to upgrade" section) is:

- If you have an Ultra 1/Ultra 2 with a processor
	<= 200 MHz, then don't run in 64-bit mode
	if you have any untrusted local users.

	A processor errata on the UltraSPARC-I
	processor (as installed in such systems)
	means that in 64-bit mode any logged-in user
	can generate an instruction that will cause
	a system crash--similar to the Intel Pentium
	F00F bug.  All Ultra 1 systems are affected
	by this, but only the slower Ultra 2s.  You
	can find the processor speed info easily
	using the module-info command at the OpenBoot
	prompt.

IIRC some similar language is already in the hardware
FAQ...but what I was thinking when I assembled the
list in my last e-mail was that a lot of folks could
probably benefit from a more targeted discussion
of the suitability of older Suns to specific tasks,
and which OS versions should be run for what reasons.

  --Rip

> > I think Rip is pointing out the FOOF-like bug the U1s
> > suffer from-- any moron luser can hard-lock the box by
> > feeding it the right invalid instructions. Unless you
> > trust your users, < 200Mhz U1s in 64bit mode isn't
> > that good a move.
> 
>   Not to point out the obvious, but...Not all applications 
> involve users
> logged into the box.
>