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To: pieter@thedarkside.nl
From: Hideki EIRAKU <hdk_2@yahoo.co.jp>
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Cc: freebsd-security@freebsd.org
Subject: Re: Protecting against kernel NULL-pointer derefs
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From: Pieter de Boer <pieter@thedarkside.nl>
Subject: Protecting against kernel NULL-pointer derefs
Date: Tue, 15 Sep 2009 10:03:48 +0200

> - Are there unwanted side-effects of raising VM_MIN_ADDRESS?

Mapping at address 0x0 is needed by some softwares using vm86 mode.
For example, emulators/doscmd uses vm86 mode to emulate an old DOS
environment. In this case, the address 0x0 - 0x3ff is used for an
interrupt vector of emulated DOS world. If VM_MIN_ADDRESS is not zero,
doscmd doesn't work. vm86 mode is in 32bit i386 architecture only, not
in amd64 or other architectures.

-- 
Hideki EIRAKU
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