x86 User-Mode Instruction Prevention and winehq

[Alexandre Julliard]

"Neri, Ricardo" <ricardo.neri at intel.com> writes:

> If running in protected mode, always propagate the GP fault to the user
> space via a sigsegv. If running in vm86 mode, trap the GP fault within
> the kernel and give the userspace fake values for the aforementioned
> resources (most likely zeros).
>
> Also, UMIP will be able to be disabled via a kernel command-line
> parameter at boot.
>
> I would like to inquire about the current use of these instructions and
> whether it would be catastrophic for wine to lose access to them.

There are apps that use these instructions, so we'll need to catch and
emulate them in the segfault handler. We have the infrastructure in
place for that sort of thing so it shouldn't be hard. It does mean that
these apps would get broken until users upgrade Wine though.

-- 
Alexandre Julliard
julliard at winehq.org