Re: [PATCH 0/4] x86: enable User-Mode Instruction Prevention

[Peter Zijlstra]

On Mon, Nov 07, 2016 at 10:12:09PM -0800, Ricardo Neri wrote:
> There is a caveat, however. Certain applications running in virtual-8086
> mode, such as DOSEMU[1] and Wine[2], want to utilize the SGDT, SIDT and
> SLDT instructions for legitimate reasons. In order to keep such
> applications working, UMIP must be disabled/enabled when entering/exiting
> virtual-8086 mode. 

Would it not be better to emulate these instructions for them? What way
we can verify they're not malicious.