Re: [PATCH 0/7] objtool: retpoline validation

[Peter Zijlstra]

On Thu, Feb 01, 2018 at 04:51:35PM +0000, David Woodhouse wrote:
> > Ideally we'd have a way to mark the module 'unsafe' or something.
> 
> No, we just need to set IBRS before doing it. 

That would work, assuming IBRS is available to begin with of course. Do
we WARN if we hit this code and don't have IBRS available?

> The same applies to any
> EFI runtime calls, APM and all kinds of other random crap that calls
> into firmware. I'm not sure why those aren't showing up.

arch/x86/platform/efi/Makefile:OBJECT_FILES_NON_STANDARD_efi_thunk_$(BITS).o := y
arch/x86/platform/efi/Makefile:OBJECT_FILES_NON_STANDARD_efi_stub_$(BITS).o := y

And similar things tell objtool to please not look..