Protecting against kernel NULL-pointer derefs
Hideki EIRAKU
hdk_2 at yahoo.co.jp
Fri Sep 18 15:39:56 UTC 2009
From: Pieter de Boer <pieter at 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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