I'm unsure of the specifics netbsd uses, but FWIW...

In some mail from Peter Jeremy, sie said:
> From owner-freebsd-hackers@FreeBSD.ORG Mon May 18 09:45:32 EST 1998
> Date: Mon, 18 May 1998 08:18:41 +1000 (EST)
> From: Peter Jeremy <peter.jeremy@alcatel.com.au>
> Subject: Pentium F00F bug
> To: freebsd-hackers@FreeBSD.ORG
> Message-Id: <199805172218.IAA03007@gsms01.alcatel.com.au>
> Sender: owner-freebsd-hackers@FreeBSD.ORG
> X-Loop: FreeBSD.ORG
> 
> There's an interesting article on the F00F bug by Robert Collins
> <rcollins@x86.org> in May Dr Dobbs Journal.  He discusses the adverse
> impacts of Intel's recommended work-arounds (one of which we use).
> 
> Robert suggests alternative solutions, which rely on interactions
> between the bug and the cache, rather than the page fault microcode.
> These solutions uses the same cross-page IDT alignment as Intel, but
> mark the first page non-cacheable - either set PTE.PCD=1 or PTE.PWT=1.
> 
> The major benefit of this approach is that the exception handlers all
> vector directly to the appropriate interrupt handler - no kludges in
> the page-fault handler are needed.
> 
> Has anyone looked into using these work-arounds instead?
> 
> Peter
> --
> Peter Jeremy (VK2PJ)                    peter.jeremy@alcatel.com.au
> Alcatel Australia Limited
> 41 Mandible St                          Phone: +61 2 9690 5019
> ALEXANDRIA  NSW  2015                   Fax:   +61 2 9690 5247
> 
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