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Diffstat (limited to 'virt/kvm/arm/psci.c')
-rw-r--r--virt/kvm/arm/psci.c40
1 files changed, 40 insertions, 0 deletions
diff --git a/virt/kvm/arm/psci.c b/virt/kvm/arm/psci.c
index 14a162e295a9..ae364716ee40 100644
--- a/virt/kvm/arm/psci.c
+++ b/virt/kvm/arm/psci.c
@@ -186,6 +186,33 @@ static void kvm_psci_system_reset(struct kvm_vcpu *vcpu)
kvm_prepare_system_event(vcpu, KVM_SYSTEM_EVENT_RESET);
}
+static void kvm_psci_narrow_to_32bit(struct kvm_vcpu *vcpu)
+{
+ int i;
+
+ /*
+ * Zero the input registers' upper 32 bits. They will be fully
+ * zeroed on exit, so we're fine changing them in place.
+ */
+ for (i = 1; i < 4; i++)
+ vcpu_set_reg(vcpu, i, lower_32_bits(vcpu_get_reg(vcpu, i)));
+}
+
+static unsigned long kvm_psci_check_allowed_function(struct kvm_vcpu *vcpu, u32 fn)
+{
+ switch(fn) {
+ case PSCI_0_2_FN64_CPU_SUSPEND:
+ case PSCI_0_2_FN64_CPU_ON:
+ case PSCI_0_2_FN64_AFFINITY_INFO:
+ /* Disallow these functions for 32bit guests */
+ if (vcpu_mode_is_32bit(vcpu))
+ return PSCI_RET_NOT_SUPPORTED;
+ break;
+ }
+
+ return 0;
+}
+
static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu)
{
struct kvm *kvm = vcpu->kvm;
@@ -193,6 +220,10 @@ static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu)
unsigned long val;
int ret = 1;
+ val = kvm_psci_check_allowed_function(vcpu, psci_fn);
+ if (val)
+ goto out;
+
switch (psci_fn) {
case PSCI_0_2_FN_PSCI_VERSION:
/*
@@ -210,12 +241,16 @@ static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu)
val = PSCI_RET_SUCCESS;
break;
case PSCI_0_2_FN_CPU_ON:
+ kvm_psci_narrow_to_32bit(vcpu);
+ fallthrough;
case PSCI_0_2_FN64_CPU_ON:
mutex_lock(&kvm->lock);
val = kvm_psci_vcpu_on(vcpu);
mutex_unlock(&kvm->lock);
break;
case PSCI_0_2_FN_AFFINITY_INFO:
+ kvm_psci_narrow_to_32bit(vcpu);
+ fallthrough;
case PSCI_0_2_FN64_AFFINITY_INFO:
val = kvm_psci_vcpu_affinity_info(vcpu);
break;
@@ -256,6 +291,7 @@ static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu)
break;
}
+out:
smccc_set_retval(vcpu, val, 0, 0, 0);
return ret;
}
@@ -273,6 +309,10 @@ static int kvm_psci_1_0_call(struct kvm_vcpu *vcpu)
break;
case PSCI_1_0_FN_PSCI_FEATURES:
feature = smccc_get_arg1(vcpu);
+ val = kvm_psci_check_allowed_function(vcpu, feature);
+ if (val)
+ break;
+
switch(feature) {
case PSCI_0_2_FN_PSCI_VERSION:
case PSCI_0_2_FN_CPU_SUSPEND: