On 1/18/21 12:03 PM, Paolo Bonzini wrote:
On 16/01/21 06:40, Tom Lendacky wrote:
Introduce a new Kconfig, AMD_SEV_ES_GUEST, to control the inclusion of
support for running as an SEV-ES guest. Pivoting on AMD_MEM_ENCRYPT for
guest SEV-ES support is undesirable for host-only kernel builds as
AMD_MEM_ENCRYPT is also required to enable KVM/host support for SEV and
SEV-ES.
I believe only KVM_AMD_SEV is required to enable the KVM support to run
SEV and SEV-ES guests. The AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT setting is
only used to determine whether to enable the KVM SEV/SEV-ES support by
default on module load.
Right:
if (IS_ENABLED(CONFIG_KVM_AMD_SEV) && sev) {
sev_hardware_setup();
} else {
sev = false;
sev_es = false;
}
I removed the addition to "config AMD_MEM_ENCRYPT_ from Sean's patch, but
(despite merging it not once but twice) I don't really like the hidden
dependency on AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT and thus AMD_MEM_ENCRYPT.
Is there any reason to not always enable sev/sev_es by default?
I don't remember where the AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT suggestion
originally came from. I thought it was from review feedback on the
original SEV patches, but can't find anything about it. @Brijesh might
remember.
But I see no reason not to enable them by default.
Thanks,
Tom
Paolo
