Re: [PATCH v2 04/39] x86/cpufeatures: Enable CET CR4 bit for shadow stack

From: Borislav Petkov
Date: Fri Oct 14 2022 - 15:45:01 EST


On Fri, Oct 14, 2022 at 06:15:30PM +0000, Edgecombe, Rick P wrote:
> Andrew Cooper has suggested to create some software cpu features to
> differentiate user/supervisor CET feature use. It could replace
> HAS_KERNEL_IBT. Any objections to that versus Kconfig symbols?

Sure, except you can't use them in

arch/x86/include/asm/idtentry.h:8:#define IDT_ALIGN (8 * (1 + HAS_KERNEL_IBT))

as that gets used in asm code.

But you don't have to do this in this patchset - it is huge already
anyway. I have this thing on my todo so I'll get to it eventually.
Unless you're itching to remove it yourself - then I won't stay in the
way.

:-)

Thx.

--
Regards/Gruss,
Boris.

https://people.kernel.org/tglx/notes-about-netiquette