# Re: \[PATCH 02/11\] x86/sev: Add an x86 version of prot\_guest\_has()

- From: Joerg Roedel \<joro@8bytes.org\>
- Date: 2021-08-02 10:35:53 
- List: linux-efi
- Page: https://ratatoskr.run/linux-efi/2021/08/211436
- Thread: https://ratatoskr.run/linuxppc-dev/2021/07/211118/t.md

```text
On Tue, Jul 27, 2021 at 05:26:05PM -0500, Tom Lendacky wrote:
> Introduce an x86 version of the prot_guest_has() function. This will be
> used in the more generic x86 code to replace vendor specific calls like
> sev_active(), etc.
> 
> While the name suggests this is intended mainly for guests, it will
> also be used for host memory encryption checks in place of sme_active().
> 
> The amd_prot_guest_has() function does not use EXPORT_SYMBOL_GPL for the
> same reasons previously stated when changing sme_active(), sev_active and
> sme_me_mask to EXPORT_SYBMOL:
>   commit 87df26175e67 ("x86/mm: Unbreak modules that rely on external PAGE_KERNEL availability")
>   commit 9d5f38ba6c82 ("x86/mm: Unbreak modules that use the DMA API")
> 
> Cc: Thomas Gleixner <redacted>
> Cc: Ingo Molnar <mingo@redhat.com>
> Cc: Borislav Petkov <bp@alien8.de>
> Cc: Dave Hansen <dave.hansen@linux.intel.com>
> Cc: Andy Lutomirski <luto@kernel.org>
> Cc: Peter Zijlstra <peterz@infradead.org>
> Co-developed-by: Andi Kleen <redacted>
> Signed-off-by: Andi Kleen <redacted>
> Co-developed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
> Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>

Reviewed-by: Joerg Roedel <redacted>
```