[PATCH 4.14 086/195] [Variant 2/Spectre-v2] arm/arm64: KVM: Turn kvm_psci_version into a static inline

[Greg Kroah-Hartman]

4.14-stable review patch.  If anyone has any objections, please let me know.

--

From: Marc Zyngier 


Commit a4097b351118 upstream.

We're about to need kvm_psci_version in HYP too. So let's turn it
into a static inline, and pass the kvm structure as a second
parameter (so that HYP can do a kern_hyp_va on it).

Tested-by: Ard Biesheuvel 
Reviewed-by: Christoffer Dall 
Signed-off-by: Marc Zyngier 
Signed-off-by: Catalin Marinas 
Signed-off-by: Will Deacon 
Signed-off-by: Ard Biesheuvel 
Signed-off-by: Greg Kroah-Hartman 
---
 arch/arm64/kvm/hyp/switch.c |   18 +++---
 include/kvm/arm_psci.h  |   21 -
 virt/kvm/arm/psci.c |   12 ++--
 3 files changed, 33 insertions(+), 18 deletions(-)

--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -19,6 +19,8 @@
 #include 
 #include 
 
+#include 
+
 #include 
 #include 
 #include 
@@ -325,14 +327,16 @@ again:
 
if (exit_code == ARM_EXCEPTION_TRAP &&
(kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_HVC64 ||
-kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_HVC32) &&
-   vcpu_get_reg(vcpu, 0) == PSCI_0_2_FN_PSCI_VERSION) {
-   u64 val = PSCI_RET_NOT_SUPPORTED;
-   if (test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features))
-   val = 2;
+kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_HVC32)) {
+   u32 val = vcpu_get_reg(vcpu, 0);
 
-   vcpu_set_reg(vcpu, 0, val);
-   goto again;
+   if (val == PSCI_0_2_FN_PSCI_VERSION) {
+   val = kvm_psci_version(vcpu, kern_hyp_va(vcpu->kvm));
+   if (unlikely(val == KVM_ARM_PSCI_0_1))
+   val = PSCI_RET_NOT_SUPPORTED;
+   vcpu_set_reg(vcpu, 0, val);
+   goto again;
+   }
}
 
if (static_branch_unlikely(_v2_cpuif_trap) &&
--- a/include/kvm/arm_psci.h
+++ b/include/kvm/arm_psci.h
@@ -18,6 +18,7 @@
 #ifndef __KVM_ARM_PSCI_H__
 #define __KVM_ARM_PSCI_H__
 
+#include 
 #include 
 
 #define KVM_ARM_PSCI_0_1   PSCI_VERSION(0, 1)
@@ -26,7 +27,25 @@
 
 #define KVM_ARM_PSCI_LATESTKVM_ARM_PSCI_1_0
 
-int kvm_psci_version(struct kvm_vcpu *vcpu);
+/*
+ * We need the KVM pointer independently from the vcpu as we can call
+ * this from HYP, and need to apply kern_hyp_va on it...
+ */
+static inline int kvm_psci_version(struct kvm_vcpu *vcpu, struct kvm *kvm)
+{
+   /*
+* Our PSCI implementation stays the same across versions from
+* v0.2 onward, only adding the few mandatory functions (such
+* as FEATURES with 1.0) that are required by newer
+* revisions. It is thus safe to return the latest.
+*/
+   if (test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features))
+   return KVM_ARM_PSCI_LATEST;
+
+   return KVM_ARM_PSCI_0_1;
+}
+
+
 int kvm_hvc_call_handler(struct kvm_vcpu *vcpu);
 
 #endif /* __KVM_ARM_PSCI_H__ */
--- a/virt/kvm/arm/psci.c
+++ b/virt/kvm/arm/psci.c
@@ -123,7 +123,7 @@ static unsigned long kvm_psci_vcpu_on(st
if (!vcpu)
return PSCI_RET_INVALID_PARAMS;
if (!vcpu->arch.power_off) {
-   if (kvm_psci_version(source_vcpu) != KVM_ARM_PSCI_0_1)
+   if (kvm_psci_version(source_vcpu, kvm) != KVM_ARM_PSCI_0_1)
return PSCI_RET_ALREADY_ON;
else
return PSCI_RET_INVALID_PARAMS;
@@ -232,14 +232,6 @@ static void kvm_psci_system_reset(struct
kvm_prepare_system_event(vcpu, KVM_SYSTEM_EVENT_RESET);
 }
 
-int kvm_psci_version(struct kvm_vcpu *vcpu)
-{
-   if (test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features))
-   return KVM_ARM_PSCI_LATEST;
-
-   return KVM_ARM_PSCI_0_1;
-}
-
 static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu)
 {
struct kvm *kvm = vcpu->kvm;
@@ -397,7 +389,7 @@ static int kvm_psci_0_1_call(struct kvm_
  */
 static int kvm_psci_call(struct kvm_vcpu *vcpu)
 {
-   switch (kvm_psci_version(vcpu)) {
+   switch (kvm_psci_version(vcpu, vcpu->kvm)) {
case KVM_ARM_PSCI_1_0:
return kvm_psci_1_0_call(vcpu);
case KVM_ARM_PSCI_0_2:

[PATCH 4.14 086/195] [Variant 2/Spectre-v2] arm/arm64: KVM: Turn kvm_psci_version into a static inline

[Greg Kroah-Hartman]

4.14-stable review patch.  If anyone has any objections, please let me know.

--

From: Marc Zyngier 


Commit a4097b351118 upstream.

We're about to need kvm_psci_version in HYP too. So let's turn it
into a static inline, and pass the kvm structure as a second
parameter (so that HYP can do a kern_hyp_va on it).

Tested-by: Ard Biesheuvel 
Reviewed-by: Christoffer Dall 
Signed-off-by: Marc Zyngier 
Signed-off-by: Catalin Marinas 
Signed-off-by: Will Deacon 
Signed-off-by: Ard Biesheuvel 
Signed-off-by: Greg Kroah-Hartman 
---
 arch/arm64/kvm/hyp/switch.c |   18 +++---
 include/kvm/arm_psci.h  |   21 -
 virt/kvm/arm/psci.c |   12 ++--
 3 files changed, 33 insertions(+), 18 deletions(-)

--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -19,6 +19,8 @@
 #include 
 #include 
 
+#include 
+
 #include 
 #include 
 #include 
@@ -325,14 +327,16 @@ again:
 
if (exit_code == ARM_EXCEPTION_TRAP &&
(kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_HVC64 ||
-kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_HVC32) &&
-   vcpu_get_reg(vcpu, 0) == PSCI_0_2_FN_PSCI_VERSION) {
-   u64 val = PSCI_RET_NOT_SUPPORTED;
-   if (test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features))
-   val = 2;
+kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_HVC32)) {
+   u32 val = vcpu_get_reg(vcpu, 0);
 
-   vcpu_set_reg(vcpu, 0, val);
-   goto again;
+   if (val == PSCI_0_2_FN_PSCI_VERSION) {
+   val = kvm_psci_version(vcpu, kern_hyp_va(vcpu->kvm));
+   if (unlikely(val == KVM_ARM_PSCI_0_1))
+   val = PSCI_RET_NOT_SUPPORTED;
+   vcpu_set_reg(vcpu, 0, val);
+   goto again;
+   }
}
 
if (static_branch_unlikely(_v2_cpuif_trap) &&
--- a/include/kvm/arm_psci.h
+++ b/include/kvm/arm_psci.h
@@ -18,6 +18,7 @@
 #ifndef __KVM_ARM_PSCI_H__
 #define __KVM_ARM_PSCI_H__
 
+#include 
 #include 
 
 #define KVM_ARM_PSCI_0_1   PSCI_VERSION(0, 1)
@@ -26,7 +27,25 @@
 
 #define KVM_ARM_PSCI_LATESTKVM_ARM_PSCI_1_0
 
-int kvm_psci_version(struct kvm_vcpu *vcpu);
+/*
+ * We need the KVM pointer independently from the vcpu as we can call
+ * this from HYP, and need to apply kern_hyp_va on it...
+ */
+static inline int kvm_psci_version(struct kvm_vcpu *vcpu, struct kvm *kvm)
+{
+   /*
+* Our PSCI implementation stays the same across versions from
+* v0.2 onward, only adding the few mandatory functions (such
+* as FEATURES with 1.0) that are required by newer
+* revisions. It is thus safe to return the latest.
+*/
+   if (test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features))
+   return KVM_ARM_PSCI_LATEST;
+
+   return KVM_ARM_PSCI_0_1;
+}
+
+
 int kvm_hvc_call_handler(struct kvm_vcpu *vcpu);
 
 #endif /* __KVM_ARM_PSCI_H__ */
--- a/virt/kvm/arm/psci.c
+++ b/virt/kvm/arm/psci.c
@@ -123,7 +123,7 @@ static unsigned long kvm_psci_vcpu_on(st
if (!vcpu)
return PSCI_RET_INVALID_PARAMS;
if (!vcpu->arch.power_off) {
-   if (kvm_psci_version(source_vcpu) != KVM_ARM_PSCI_0_1)
+   if (kvm_psci_version(source_vcpu, kvm) != KVM_ARM_PSCI_0_1)
return PSCI_RET_ALREADY_ON;
else
return PSCI_RET_INVALID_PARAMS;
@@ -232,14 +232,6 @@ static void kvm_psci_system_reset(struct
kvm_prepare_system_event(vcpu, KVM_SYSTEM_EVENT_RESET);
 }
 
-int kvm_psci_version(struct kvm_vcpu *vcpu)
-{
-   if (test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features))
-   return KVM_ARM_PSCI_LATEST;
-
-   return KVM_ARM_PSCI_0_1;
-}
-
 static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu)
 {
struct kvm *kvm = vcpu->kvm;
@@ -397,7 +389,7 @@ static int kvm_psci_0_1_call(struct kvm_
  */
 static int kvm_psci_call(struct kvm_vcpu *vcpu)
 {
-   switch (kvm_psci_version(vcpu)) {
+   switch (kvm_psci_version(vcpu, vcpu->kvm)) {
case KVM_ARM_PSCI_1_0:
return kvm_psci_1_0_call(vcpu);
case KVM_ARM_PSCI_0_2: