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Subject[patch] vm86: fix IOPL virtualisation
Hello.

The attached patch implements the following:
http://x86.ddj.com/articles/vme1/vme_overview.htm
---
In addition to moving the VIF to the IF on the stack image,
PUSHF always pushes an IOPL image of 3 onto the
stack.
---

Many DOS programs, including dos4gw, are
checking if they are in a v86 mode by trying
to alter IOPL. With that patch they are not
get confused under dosemu.
Also the patch fixes what looks like a bug
with an IF flag.
--- linux/arch/i386/kernel/vm86.c Sun Aug 4 03:44:30 2002
+++ linux/arch/i386/kernel/vm86.c Sat May 24 19:30:45 2003
@@ -362,6 +362,9 @@

if (VEFLAGS & VIF_MASK)
flags |= IF_MASK;
+ else
+ flags &= ~IF_MASK;
+ flags |= IOPL_MASK;
return flags | (VEFLAGS & current->thread.v86mask);
}
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