[PATCH v2 03/14] KVM: SVM: Move SEV module params/variables to sev.c

Sean Christopherson
2021-01-14T01:48:49Z

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'.

Signed-off-by: Sean Christopherson <seanjc@google.com>
---
arch/x86/kvm/svm/sev.c | 11 +++++++++++
arch/x86/kvm/svm/svm.c | 15 +--------------
arch/x86/kvm/svm/svm.h | 2 --
3 files changed, 12 insertions(+), 16 deletions(-)

diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 0eeb6e1b803d..8ba93b8fa435 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -27,6 +27,14 @@

#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);
@@ -1249,6 +1257,9 @@ void __init sev_hardware_setup(void)
bool sev_es_supported = false;
bool sev_supported = false;

+ if (!IS_ENABLED(CONFIG_KVM_AMD_SEV) || !sev)
+ 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 ccf52c5531fb..f89f702b2a58 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -189,14 +189,6 @@ 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);

@@ -976,12 +968,7 @@ static __init int svm_hardware_setup(void)
kvm_enable_efer_bits(EFER_SVME | EFER_LMSLE);
}

- if (IS_ENABLED(CONFIG_KVM_AMD_SEV) && sev) {
- sev_hardware_setup();
- } else {
- sev = false;
- sev_es = false;
- }
+ sev_hardware_setup();

svm_adjust_mmio_mask();

diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
index 0fe874ae5498..8e169835f52a 100644
--- a/arch/x86/kvm/svm/svm.h
+++ b/arch/x86/kvm/svm/svm.h
@@ -408,8 +408,6 @@ static inline bool gif_set(struct vcpu_svm *svm)
#define MSR_CR3_LONG_MBZ_MASK 0xfff0000000000000U
#define MSR_INVALID 0xffffffffU

-extern int sev;
-extern int sev_es;
extern bool dump_invalid_vmcb;

u32 svm_msrpm_offset(u32 msr);
--
2.30.0.284.gd98b1dd5eaa7-goog