[PATCH v7 08/22] coco: arm64: s390: powerpc: Mark secure guests with CC_ATTR_GUEST_MEM_ENCRYPT

Suzuki K Poulose suzuki.poulose at arm.com
Tue Jul 7 08:41:40 PDT 2026


On 01/07/2026 06:49, Aneesh Kumar K.V (Arm) wrote:
> arm64 Realms, powerpc secure guests and s390 protected virtualization
> guests currently report CC_ATTR_MEM_ENCRYPT, but not
> CC_ATTR_GUEST_MEM_ENCRYPT.
> 
> These environments are all secure guest configurations. Their
> force_dma_unencrypted() implementations also treat the same secure guest
> state as requiring unencrypted DMA. Report CC_ATTR_GUEST_MEM_ENCRYPT for
> the same condition so generic confidential-computing code can distinguish
> guest memory encryption from host memory encryption instead of relying only
> on CC_ATTR_MEM_ENCRYPT.
> 
> Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar at kernel.org>


For arm64 bits:



> ---
>   arch/arm64/kernel/rsi.c                      | 1 +
>   arch/powerpc/platforms/pseries/cc_platform.c | 1 +
>   arch/s390/mm/init.c                          | 1 +
>   3 files changed, 3 insertions(+)
> 
> diff --git a/arch/arm64/kernel/rsi.c b/arch/arm64/kernel/rsi.c
> index 92160f2e57ff..207e36db1e7a 100644
> --- a/arch/arm64/kernel/rsi.c
> +++ b/arch/arm64/kernel/rsi.c
> @@ -27,6 +27,7 @@ bool cc_platform_has(enum cc_attr attr)
>   {
>   	switch (attr) {
>   	case CC_ATTR_MEM_ENCRYPT:
> +	case CC_ATTR_GUEST_MEM_ENCRYPT:
>   		return is_realm_world();
>   	default:
>   		return false;

Reviewed-by: Suzuki K Poulose <suzuki.poulose at arm.com>


Suzuki



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