Re: [PATCH v6 02/76] KVM: SVM: Add GHCB definitions

Arvind Sankar
2020-08-27T16:01:23Z

On Tue, Aug 25, 2020 at 01:04:46PM +0200, Borislav Petkov wrote:
> On Tue, Aug 25, 2020 at 11:22:24AM +0200, Joerg Roedel wrote:
> > I don't think so, if I look at the history of these checks their whole
> > purpose seems to be to alert the developer/maintainer when their size
> > changes and that they might not fit on the stack anymore. But that is
> > taken care of in patch 1.
>
> Why? What's wrong with:
>
> BUILD_BUG_ON(sizeof(struct vmcb_save_area) != VMCB_SAVE_AREA_SIZE);
> BUILD_BUG_ON(sizeof(struct vmcb_control_area) != VMCB_CONTROL_AREA_SIZE);
> BUILD_BUG_ON(sizeof(struct ghcb) != PAGE_SIZE);
>
> ?
>
> --
> Regards/Gruss,
> Boris.
>
> https://people.kernel.org/tglx/notes-about-netiquette

Wouldn't we rather just remove the checks?