[PATCH v2 4/4] x86/cpu: clear SEV/SEV_ES features when not in use

[Mario Limonciello]

As there are no consumers for these feature flags in the kernel,
don't export these flags to userspace unless the feature has been
enabled by the guest.

Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
---
 arch/x86/kernel/cpu/amd.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 9cea774344cb..6623a4995df1 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -614,12 +614,19 @@ static void early_detect_mem_encrypt(struct cpuinfo_x86 *c)
 		if (!(msr & MSR_K7_HWCR_SMMLOCK))
 			goto clear_sev;
 
+		if (!(sev_status & MSR_AMD64_SEV_ENABLED))
+			goto clear_sev;
+
+		if (!(sev_status & MSR_AMD64_SEV_ES_ENABLED))
+			goto clear_sev_es;
+
 		return;
 
 clear_all:
 		setup_clear_cpu_cap(X86_FEATURE_SME);
 clear_sev:
 		setup_clear_cpu_cap(X86_FEATURE_SEV);
+clear_sev_es:
 		setup_clear_cpu_cap(X86_FEATURE_SEV_ES);
 	}
 }
-- 
2.34.1