Re: [PATCH] efi/x86: use naked RET on mixed mode call wrapper

On Mon, Jul 18, 2022 at 11:34:02AM -0700, Linus Torvalds wrote:

Why would we have to protect the kernel from EFI?

Yes, we cleared this up on IRC in the meantime.

This was raised as a concern in case we don't trust EFI. But we cannot not (double negation on purpose) trust EFI because it can do whatever it likes anyway, "underneath" the OS.

I'm keeping the UNTRAIN_RET-in-C diff in my patches/ folder, though - I get the feeling we might need it soon for something else.

:-)