[v5,04/15] KVM: SVM: Move SEV module params/variables to sev.c

Commit Message

Sean Christopherson April 22, 2021, 2:11 a.m. UTC

Unconditionally invoke sev_hardware_setup() when configuring SVM and
handle clearing the module params/variable 'sev' and 'sev_es' in
sev_hardware_setup().  This allows making said variables static within
sev.c and reduces the odds of a collision with guest code, e.g. the guest
side of things has already laid claim to 'sev_enabled'.

Reviewed-by: Tom Lendacky <[e-mail]>
Reviewed-by: Brijesh Singh <[e-mail]>
Signed-off-by: Sean Christopherson <[e-mail]>
---
 arch/x86/kvm/svm/sev.c | 11 +++++++++++
 arch/x86/kvm/svm/svm.c | 16 ++--------------
 arch/x86/kvm/svm/svm.h |  2 --
 3 files changed, 13 insertions(+), 16 deletions(-)

Patch

diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 5ff8a202cc01..fb32b93e325c 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -28,6 +28,14 @@ 
 
 #define __ex(x) __kvm_handle_fault_on_reboot(x)
 
+/* enable/disable SEV support */
+static int sev = IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT);
+module_param(sev, int, 0444);
+
+/* enable/disable SEV-ES support */
+static int sev_es = IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT);
+module_param(sev_es, int, 0444);
+
 static u8 sev_enc_bit;
 static int sev_flush_asids(void);
 static DECLARE_RWSEM(sev_deactivate_lock);
@@ -1762,6 +1770,9 @@  void __init sev_hardware_setup(void)
 	bool sev_es_supported = false;
 	bool sev_supported = false;
 
+	if (!IS_ENABLED(CONFIG_KVM_AMD_SEV) || !sev || !npt_enabled)
+		goto out;
+
 	/* Does the CPU support SEV? */
 	if (!boot_cpu_has(X86_FEATURE_SEV))
 		goto out;
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 0e8489908216..12b2c04076bb 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -185,14 +185,6 @@  module_param(vls, int, 0444);
 static int vgif = true;
 module_param(vgif, int, 0444);
 
-/* enable/disable SEV support */
-int sev = IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT);
-module_param(sev, int, 0444);
-
-/* enable/disable SEV-ES support */
-int sev_es = IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT);
-module_param(sev_es, int, 0444);
-
 bool __read_mostly dump_invalid_vmcb;
 module_param(dump_invalid_vmcb, bool, 0644);
 
@@ -984,12 +976,8 @@  static __init int svm_hardware_setup(void)
 	kvm_configure_mmu(npt_enabled, get_max_npt_level(), PG_LEVEL_1G);
 	pr_info("kvm: Nested Paging %sabled\n", npt_enabled ? "en" : "dis");
 
-	if (IS_ENABLED(CONFIG_KVM_AMD_SEV) && sev && npt_enabled) {
-		sev_hardware_setup();
-	} else {
-		sev = false;
-		sev_es = false;
-	}
+	/* Note, SEV setup consumes npt_enabled. */
+	sev_hardware_setup();
 
 	svm_adjust_mmio_mask();
 
diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
index 454da1c1d9b7..ec0407f41458 100644
--- a/arch/x86/kvm/svm/svm.h
+++ b/arch/x86/kvm/svm/svm.h
@@ -397,8 +397,6 @@  static inline bool gif_set(struct vcpu_svm *svm)
 /* svm.c */
 #define MSR_INVALID				0xffffffffU
 
-extern int sev;
-extern int sev_es;
 extern bool dump_invalid_vmcb;
 
 u32 svm_msrpm_offset(u32 msr);