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From: Wee Teck Ng <weeteck@eecs.umich.edu>
Message-Id: <199709270523.BAA07578@singapore.eecs.umich.edu>
Subject: using vm_map_protect on Pentium PC
To: freebsd-hackers@freebsd.org
Date: Sat, 27 Sep 1997 01:23:44 -0400 (EDT)
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hi all,

we are heavily utilising VM protection (vm_map_prot) on 2.2-stable,
and found that it doesn't work well on Pentium processor. specifically,
when using vm_map_prot to change a page's protection from VM_PROT_READ 
to VM_PROT_ALL, only the vm map is updated. pmap_protect does not reset 
the pte to writeable (i.e. PG_RW). this will not work on pentium processor,
since page level protection is enforced by the processor (against kernel
access) when WP flag of CR0 is set.

i've noticed that FreeBSD-current has fixed this problem. my questions are:
	1) is there a 2.x release with a Pentium-compatible VM system?
	2) how stable is 3.0 is for non SMP machines?

thanks!
wee teck