Date: Mon, 11 Jun 2001 15:54:01 -0700 (PDT) From: Matt Dillon <dillon@earth.backplane.com> To: Jonathan Lemon <jlemon@flugsvamp.com> Cc: mikulas@artax.karlin.mff.cuni.cz, hackers@FreeBSD.ORG Subject: Re: Patented algorithm in FreeBSD Message-ID: <200106112254.f5BMs1b33854@earth.backplane.com> References: <200106112237.f5BMbuh06004@prism.flugsvamp.com>
next in thread | previous in thread | raw e-mail | index | archive | help
:Hmm, let's see:
:
: Assignee: Digital Equipment Corporation (Maynard, MA)
: Appl. No.: 646734
: Filed: May 3, 1996
:
:Versus:
:
: * Derived from hp300 version by Mike Hibler, this version by William
: * Jolitz uses a recursive map [a pde points to the page directory] to
: * map the page tables using the pagetables themselves. This is done to
: * reduce the impact on kernel virtual memory for lots of sparse address
: * space, and to reduce the cost of memory to each process.
: *
: * from: hp300: @(#)pmap.h 7.2 (Berkeley) 12/16/90
: * from: @(#)pmap.h 7.4 (Berkeley) 5/12/91
:
:
:So it looks like we have prior art by around 6 years, which would
:invalidate the patent iff it was the same thing.
:
:(Not that I've read the patent, but typically the invention must meet
: *ALL* the claims being described; one small deviation and it is
: considered to be different.)
:--
:Jonathan
I read it. It's chock full of the normal patent garbage. The abstract
basically is exactly what's been done in BSD from the early 90's (and
maybe even earlier, but I wasn't into VM in the CSRG kernels so I
don't know for sure, maybe Bruce does?). Some of the claims match up
fairly well. The patent also has all sorts of other crap in it, most
of it pretty basic. The patent examiner obviously had no clue as to
what he was examining but that's pretty much SOP these days.
Remember the idiot who patented the +/-50 2-digit year rule?
Again, nothing to worry about here.
-Matt
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-hackers" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200106112254.f5BMs1b33854>