1 files changed, 121 insertions, 0 deletions
diff --git a/tools/testing/selftests/kvm/aarch64/vcpu_width_config.c b/tools/testing/selftests/kvm/aarch64/vcpu_width_config.c
new file mode 100644
index 000000000000..80b74c6f152b
--- /dev/null
+++ b/tools/testing/selftests/kvm/aarch64/vcpu_width_config.c
@@ -0,0 +1,121 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * vcpu_width_config - Test KVM_ARM_VCPU_INIT() with KVM_ARM_VCPU_EL1_32BIT.
+ *
+ * Copyright (c) 2022 Google LLC.
+ *
+ * This is a test that ensures that non-mixed-width vCPUs (all 64bit vCPUs
+ * or all 32bit vcPUs) can be configured and mixed-width vCPUs cannot be
+ * configured.
+ */
+
+#include "kvm_util.h"
+#include "processor.h"
+#include "test_util.h"
+
+
+/*
+ * Add a vCPU, run KVM_ARM_VCPU_INIT with @init0, and then
+ * add another vCPU, and run KVM_ARM_VCPU_INIT with @init1.
+ */
+static int add_init_2vcpus(struct kvm_vcpu_init *init0,
+			   struct kvm_vcpu_init *init1)
+{
+	struct kvm_vcpu *vcpu0, *vcpu1;
+	struct kvm_vm *vm;
+	int ret;
+
+	vm = vm_create_barebones();
+
+	vcpu0 = __vm_vcpu_add(vm, 0);
+	ret = __vcpu_ioctl(vcpu0, KVM_ARM_VCPU_INIT, init0);
+	if (ret)
+		goto free_exit;
+
+	vcpu1 = __vm_vcpu_add(vm, 1);
+	ret = __vcpu_ioctl(vcpu1, KVM_ARM_VCPU_INIT, init1);
+
+free_exit:
+	kvm_vm_free(vm);
+	return ret;
+}
+
+/*
+ * Add two vCPUs, then run KVM_ARM_VCPU_INIT for one vCPU with @init0,
+ * and run KVM_ARM_VCPU_INIT for another vCPU with @init1.
+ */
+static int add_2vcpus_init_2vcpus(struct kvm_vcpu_init *init0,
+				  struct kvm_vcpu_init *init1)
+{
+	struct kvm_vcpu *vcpu0, *vcpu1;
+	struct kvm_vm *vm;
+	int ret;
+
+	vm = vm_create_barebones();
+
+	vcpu0 = __vm_vcpu_add(vm, 0);
+	vcpu1 = __vm_vcpu_add(vm, 1);
+
+	ret = __vcpu_ioctl(vcpu0, KVM_ARM_VCPU_INIT, init0);
+	if (ret)
+		goto free_exit;
+
+	ret = __vcpu_ioctl(vcpu1, KVM_ARM_VCPU_INIT, init1);
+
+free_exit:
+	kvm_vm_free(vm);
+	return ret;
+}
+
+/*
+ * Tests that two 64bit vCPUs can be configured, two 32bit vCPUs can be
+ * configured, and two mixed-width vCPUs cannot be configured.
+ * Each of those three cases, configure vCPUs in two different orders.
+ * The one is running KVM_CREATE_VCPU for 2 vCPUs, and then running
+ * KVM_ARM_VCPU_INIT for them.
+ * The other is running KVM_CREATE_VCPU and KVM_ARM_VCPU_INIT for a vCPU,
+ * and then run those commands for another vCPU.
+ */
+int main(void)
+{
+	struct kvm_vcpu_init init0, init1;
+	struct kvm_vm *vm;
+	int ret;
+
+	TEST_REQUIRE(kvm_has_cap(KVM_CAP_ARM_EL1_32BIT));
+
+	/* Get the preferred target type and copy that to init1 for later use */
+	vm = vm_create_barebones();
+	vm_ioctl(vm, KVM_ARM_PREFERRED_TARGET, &init0);
+	kvm_vm_free(vm);
+	init1 = init0;
+
+	/* Test with 64bit vCPUs */
+	ret = add_init_2vcpus(&init0, &init0);
+	TEST_ASSERT(ret == 0,
+		    "Configuring 64bit EL1 vCPUs failed unexpectedly");
+	ret = add_2vcpus_init_2vcpus(&init0, &init0);
+	TEST_ASSERT(ret == 0,
+		    "Configuring 64bit EL1 vCPUs failed unexpectedly");
+
+	/* Test with 32bit vCPUs */
+	init0.features[0] = (1 << KVM_ARM_VCPU_EL1_32BIT);
+	ret = add_init_2vcpus(&init0, &init0);
+	TEST_ASSERT(ret == 0,
+		    "Configuring 32bit EL1 vCPUs failed unexpectedly");
+	ret = add_2vcpus_init_2vcpus(&init0, &init0);
+	TEST_ASSERT(ret == 0,
+		    "Configuring 32bit EL1 vCPUs failed unexpectedly");
+
+	/* Test with mixed-width vCPUs  */
+	init0.features[0] = 0;
+	init1.features[0] = (1 << KVM_ARM_VCPU_EL1_32BIT);
+	ret = add_init_2vcpus(&init0, &init1);
+	TEST_ASSERT(ret != 0,
+		    "Configuring mixed-width vCPUs worked unexpectedly");
+	ret = add_2vcpus_init_2vcpus(&init0, &init1);
+	TEST_ASSERT(ret != 0,
+		    "Configuring mixed-width vCPUs worked unexpectedly");
+
+	return 0;
+}