Re: [PATCH v3 09/10] x86/fpu/xstate: Introduce XFEATURE_MASK_KERNEL_DYNAMIC xfeature set

Chang S. Bae
2025-03-10T05:21:08Z

On 3/9/2025 8:49 PM, Chao Gao wrote:
>
> It was suggested by Sean [1].
...
> [1]: https://lore.kernel.org/kvm/ZTf5wPKXuHBQk0AN@google.com/

But, you're defining a kernel "dynamic" feature while introducing a
"guest-only" xfeature concept. Both seem to be mixed together with this
patch. Why not call it as a guest-only feature? That's what Sean was
suggesting, no?

"I would much prefer to avoid the whole "dynamic" thing and instead make
CET explicitly guest-only. E.g. fpu_kernel_guest_only_xfeatures? Or
even better if it doesn't cause weirdness elsewhere, a dedicated
fpu_guest_cfg. For me at least, a fpu_guest_cfg would make it easier to
understand what all is going on."

Thanks,
Chang