diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index bb82a906e51e73fe6fcfa7cb0c066475930c06a6..81f1b974c06a5c8d18e2f3a22ed91862ffff154b 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -2453,6 +2453,11 @@ return ENOEXEC for that vcpu.
Note that because some registers reflect machine topology, all vcpus
should be created before this ioctl is invoked.
+Userspace can call this function multiple times for a given vcpu, including
+after the vcpu has been run. This will reset the vcpu to its initial
+state. All calls to this function after the initial call must use the same
+target and same set of feature flags, otherwise EINVAL will be returned.
+
Possible features:
- KVM_ARM_VCPU_POWER_OFF: Starts the CPU in a power-off state.
Depends on KVM_CAP_ARM_PSCI. If not set, the CPU will be powered on
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index 53036e21756b6b1efaef6e9c34e64ae3117f30d2..254e0650e48bbc1d07a81d091c8e33570f983851 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -150,8 +150,6 @@ struct kvm_vcpu_stat {
u32 halt_wakeup;
};
-int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
- const struct kvm_vcpu_init *init);
int kvm_vcpu_preferred_target(struct kvm_vcpu_init *init);
unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu);
int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices);
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index 24c9ca4076b242ffe01447e8e153307b793da96a..4043769583e7fc4e4a68311ff7703b984b1e4d83 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -263,6 +263,7 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
{
/* Force users to call KVM_ARM_VCPU_INIT */
vcpu->arch.target = -1;
+ bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
/* Set up the timer */
kvm_timer_vcpu_init(vcpu);
@@ -649,6 +650,48 @@ int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level,
return -EINVAL;
}
+static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
+ const struct kvm_vcpu_init *init)
+{
+ unsigned int i;
+ int phys_target = kvm_target_cpu();
+
+ if (init->target != phys_target)
+ return -EINVAL;
+
+ /*
+ * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must
+ * use the same target.
+ */
+ if (vcpu->arch.target != -1 && vcpu->arch.target != init->target)
+ return -EINVAL;
+
+ /* -ENOENT for unknown features, -EINVAL for invalid combinations. */
+ for (i = 0; i < sizeof(init->features) * 8; i++) {
+ bool set = (init->features[i / 32] & (1 << (i % 32)));
+
+ if (set && i >= KVM_VCPU_MAX_FEATURES)
+ return -ENOENT;
+
+ /*
+ * Secondary and subsequent calls to KVM_ARM_VCPU_INIT must
+ * use the same feature set.
+ */
+ if (vcpu->arch.target != -1 && i < KVM_VCPU_MAX_FEATURES &&
+ test_bit(i, vcpu->arch.features) != set)
+ return -EINVAL;
+
+ if (set)
+ set_bit(i, vcpu->arch.features);
+ }
+
+ vcpu->arch.target = phys_target;
+
+ /* Now we know what it is, we can reset it. */
+ return kvm_reset_vcpu(vcpu);
+}
+
+
static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu,
struct kvm_vcpu_init *init)
{
diff --git a/arch/arm/kvm/guest.c b/arch/arm/kvm/guest.c
index 8c97208b9b970c4d799e76ee7096d58dfb8c33ae..384bab67c4629a9bece251d5577c9bf908f8348f 100644
--- a/arch/arm/kvm/guest.c
+++ b/arch/arm/kvm/guest.c
@@ -273,31 +273,6 @@ int __attribute_const__ kvm_target_cpu(void)
}
}
-int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
- const struct kvm_vcpu_init *init)
-{
- unsigned int i;
-
- /* We can only cope with guest==host and only on A15/A7 (for now). */
- if (init->target != kvm_target_cpu())
- return -EINVAL;
-
- vcpu->arch.target = init->target;
- bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
-
- /* -ENOENT for unknown features, -EINVAL for invalid combinations. */
- for (i = 0; i < sizeof(init->features) * 8; i++) {
- if (test_bit(i, (void *)init->features)) {
- if (i >= KVM_VCPU_MAX_FEATURES)
- return -ENOENT;
- set_bit(i, vcpu->arch.features);
- }
- }
-
- /* Now we know what it is, we can reset it. */
- return kvm_reset_vcpu(vcpu);
-}
-
int kvm_vcpu_preferred_target(struct kvm_vcpu_init *init)
{
int target = kvm_target_cpu();
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 2012c4ba8d67bf15c484048b4a0fe5b68f8e1b94..65c615294589f242a2d62694695002882d5cc1a8 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -165,8 +165,6 @@ struct kvm_vcpu_stat {
u32 halt_wakeup;
};
-int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
- const struct kvm_vcpu_init *init);
int kvm_vcpu_preferred_target(struct kvm_vcpu_init *init);
unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu);
int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices);
diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c
index 84d5959ff8742b64d37af40046a1c4fc8bd6e641..9535bd555d1d47cf190f78306eb879484d70a261 100644
--- a/arch/arm64/kvm/guest.c
+++ b/arch/arm64/kvm/guest.c
@@ -296,31 +296,6 @@ int __attribute_const__ kvm_target_cpu(void)
return -EINVAL;
}
-int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
- const struct kvm_vcpu_init *init)
-{
- unsigned int i;
- int phys_target = kvm_target_cpu();
-
- if (init->target != phys_target)
- return -EINVAL;
-
- vcpu->arch.target = phys_target;
- bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
-
- /* -ENOENT for unknown features, -EINVAL for invalid combinations. */
- for (i = 0; i < sizeof(init->features) * 8; i++) {
- if (init->features[i / 32] & (1 << (i % 32))) {
- if (i >= KVM_VCPU_MAX_FEATURES)
- return -ENOENT;
- set_bit(i, vcpu->arch.features);
- }
- }
-
- /* Now we know what it is, we can reset it. */
- return kvm_reset_vcpu(vcpu);
-}
-
int kvm_vcpu_preferred_target(struct kvm_vcpu_init *init)
{
int target = kvm_target_cpu();