Re: [Fwd: NOTE: Solaris 7 gotcha for some ultras]

[pjm () GEMINI-RESEARCH CO UK (Paul Murphy)]

> Got a surprise when I finally installed the non-beta version of Solaris 7
> on my Ultra-2 today.  It booted to 32-bit mode instead of 64-bit, claiming
> my hardware defaulted to 32-bit mode.
>
> The message at boot time said to see the boot(1m) man page, so I
> looked, and there it was at the bottom:
>
>     On systems containing 200MHz or lower  UltraSPARC-1  proces-
>     sors,  it  is  possible  for  a user to run a 64-bit program
>     designed to exploit a problem that could cause  a  processor
>     to  stall.  Since  64-bit  progams  cannot run on the 32-bit
>     kernel, the 32-bit kernel is chosen as the default  file  on
>     these  systems.

This shouldn't come as a surprise, since Sun are talking openly about it
in their Solaris 7 seminars for system administrators (which you _have_
attended, right?).  The problem is restricted to older systems, and their
advice was that if you were at all worried about this, you should run the 32-
bit kernel for peace of mind.  Later processors are unaffected.

If they'd put the 64-bit kernel in by default, you'd criticise them for leaving
a security hole in the system.....

Paul.


------------------------------------------------------
Paul J. Murphy - Head of I.T.
Gemini Research Ltd, 162 Science Park, Cambridge
Phone: 01223 435305     Fax: 01223 435301