The emulation code for the instructions that cannot be executed in vm86
mode directly (iretd, pushf and a few others) accesses user space memory
without an exception handler. This can cause a kernel oops if the stack
pointer points to non-present or read-only memory areas.

The attached patch adds these handlers, but I can't test them properly.
Under 2.5.2-pre1, dosemu still runs.

The patch applies to both 2.4.17 and 2.2.20. Please test it.

--
	Manfred