[funsec] Description of the Intel CPU bugs

[Valdis.Kletnieks at vt.edu]

On Thu, 28 Jun 2007 11:37:39 PDT, Matthew Murphy said:
> > So the one Microsoft update has all of the microcode for all of the
> > Intel CPUs in it?
> 
> It likely has all the microcode *updates*, which may not necessarily
> contain full dupes of the microcode.  It most likely will only install
> the update relevant for your particular CPU.

That's basically what Intel releases - patches for each CPU's microcode.
Those of you who are old enough to remember HMASPZAP know the drill, including
the ever-popular 'PTCHAREA DS 12F' or whatever was deemed needed.  Yes, Intel
leaves patch space open in the microcode store. :)

About 294K of data, currently 125 chunks.  Each chunk is basically:
family, model, stepping, checksum, length, <random-looking bytes>.  There's
provisions for stripping it down, so if Dell *knows* that a particular laptop
may have one of 6 CPUs, and never one of the other 119, it can include only
those 6 CPUs in the BIOS.  The Microsoft update would of course need to carry
all 294K along.
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