From a479c334842279cc099c1f73b6bc04b1528c79b4 Mon Sep 17 00:00:00 2001
From: Sean Christopherson <seanjc@google.com>
Date: Wed, 21 Apr 2021 19:11:18 -0700
Subject: [PATCH] KVM: SVM: Condition sev_enabled and sev_es_enabled on
CONFIG_KVM_AMD_SEV=y
Define sev_enabled and sev_es_enabled as 'false' and explicitly #ifdef
out all of sev_hardware_setup() if CONFIG_KVM_AMD_SEV=n. This kills
three birds at once:
- Makes sev_enabled and sev_es_enabled off by default if
CONFIG_KVM_AMD_SEV=n. Previously, they could be on by default if
CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT=y, regardless of KVM SEV
support.
- Hides the sev and sev_es modules params when CONFIG_KVM_AMD_SEV=n.
- Resolves a false positive -Wnonnull in __sev_recycle_asids() that is
currently masked by the equivalent IS_ENABLED(CONFIG_KVM_AMD_SEV)
check in svm_sev_enabled(), which will be dropped in a future patch.
Reviewed by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210422021125.3417167-9-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
arch/x86/kvm/svm/sev.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index a6041000ed9c9..bb514d5421d96 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -44,6 +44,7 @@
#define MISC_CG_RES_SEV_ES MISC_CG_RES_TYPES
#endif
+#ifdef CONFIG_KVM_AMD_SEV
/* enable/disable SEV support */
static bool sev_enabled = IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT);
module_param_named(sev, sev_enabled, bool, 0444);
@@ -51,6 +52,10 @@ module_param_named(sev, sev_enabled, bool, 0444);
/* enable/disable SEV-ES support */
static bool sev_es_enabled = IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT);
module_param_named(sev_es, sev_es_enabled, bool, 0444);
+#else
+#define sev_enabled false
+#define sev_es_enabled false
+#endif /* CONFIG_KVM_AMD_SEV */
static u8 sev_enc_bit;
static int sev_flush_asids(void);
@@ -1817,11 +1822,12 @@ void __init sev_set_cpu_caps(void)
void __init sev_hardware_setup(void)
{
+#ifdef CONFIG_KVM_AMD_SEV
unsigned int eax, ebx, ecx, edx, sev_asid_count, sev_es_asid_count;
bool sev_es_supported = false;
bool sev_supported = false;
- if (!IS_ENABLED(CONFIG_KVM_AMD_SEV) || !sev_enabled || !npt_enabled)
+ if (!sev_enabled || !npt_enabled)
goto out;
/* Does the CPU support SEV? */
@@ -1885,6 +1891,7 @@ void __init sev_hardware_setup(void)
out:
sev_enabled = sev_supported;
sev_es_enabled = sev_es_supported;
+#endif
}
void sev_hardware_teardown(void)