From: Sagi Shahar <[email protected]> TDX VMs need to issue the KVM_TDX_INIT_VCPU ioctl for each vcpu after vcpu creation.
KVM_TDX_INIT_VCPU has a strict prerequisite for the CPUID state. To satisfy this requirement, call KVM_TDX_GET_CPUID and KVM_SET_CPUID2 to pull the CPUID configuration from the TDCS and commit it into KVM, allowing KVM_TDX_INIT_VCPU to succeed. Additionally, unlike tdx_vm_ioctl(), tdx_vcpu_ioctl() doesn't check hw_error. KVM's vCPU-scoped TDX ioctl handlers don't propagate SEAMCALL errors into hw_error: the error is handled in the kernel and only an errno is returned. Checking the ioctl's return value and errno is therefore sufficient. Signed-off-by: Sagi Shahar <[email protected]> Signed-off-by: Lisa Wang <[email protected]> --- .../selftests/kvm/include/x86/tdx/tdx_util.h | 20 +++++++++ tools/testing/selftests/kvm/lib/x86/processor.c | 48 ++++++++++++++++++---- 2 files changed, 60 insertions(+), 8 deletions(-) diff --git a/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h b/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h index e529c587aeae..f5b2f32f2118 100644 --- a/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h +++ b/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h @@ -46,6 +46,26 @@ static inline bool is_tdx_vm(struct kvm_vm *vm) (unsigned long long)hw_error); \ }) +#define __tdx_vcpu_ioctl(vcpu, cmd, _flags, arg) \ +({ \ + union { \ + struct kvm_tdx_cmd c; \ + unsigned long raw; \ + } tdx_cmd = { .c = { \ + .id = (cmd), \ + .flags = (u32)(_flags), \ + .data = (u64)(arg), \ + } }; \ + \ + __vcpu_ioctl(vcpu, KVM_MEMORY_ENCRYPT_OP, &tdx_cmd.raw); \ +}) + +#define tdx_vcpu_ioctl(vcpu, cmd, flags, arg) \ +({ \ + int ret = __tdx_vcpu_ioctl(vcpu, cmd, flags, arg); \ + TEST_ASSERT(!ret, "%s failed, errno: %d (%s)", \ + #cmd, errno, strerror(errno)); \ +}) void tdx_init_vm(struct kvm_vm *vm); void tdx_vm_setup_boot_code_region(struct kvm_vm *vm); void tdx_vm_setup_boot_parameters_region(struct kvm_vm *vm, u32 nr_runnable_vcpus); diff --git a/tools/testing/selftests/kvm/lib/x86/processor.c b/tools/testing/selftests/kvm/lib/x86/processor.c index 4a753fb43007..4af9cbf3fabb 100644 --- a/tools/testing/selftests/kvm/lib/x86/processor.c +++ b/tools/testing/selftests/kvm/lib/x86/processor.c @@ -876,16 +876,48 @@ gva_t kvm_allocate_vcpu_stack(struct kvm_vm *vm) "__vm_alloc() did not provide a page-aligned address"); stack_gva -= 8; + return stack_gva; +} + +static void tdx_vcpu_init(struct kvm_vm *vm, struct kvm_vcpu *vcpu) +{ + struct kvm_cpuid2 *cpuid; + + cpuid = allocate_kvm_cpuid2(MAX_NR_CPUID_ENTRIES); + tdx_vcpu_ioctl(vcpu, KVM_TDX_GET_CPUID, 0, cpuid); + vcpu_init_cpuid(vcpu, cpuid); + free(cpuid); + tdx_vcpu_ioctl(vcpu, KVM_TDX_INIT_VCPU, 0, NULL); +} + +struct kvm_vcpu *vm_arch_vcpu_add(struct kvm_vm *vm, u32 vcpu_id) +{ + struct kvm_mp_state mp_state; + struct kvm_vcpu *vcpu; + struct kvm_regs regs; + vcpu = __vm_vcpu_add(vm, vcpu_id); - vcpu_init_cpuid(vcpu, kvm_get_supported_cpuid()); - vcpu_init_sregs(vm, vcpu); - vcpu_init_xcrs(vm, vcpu); - /* Setup guest general purpose registers */ - vcpu_regs_get(vcpu, ®s); - regs.rflags = regs.rflags | 0x2; - regs.rsp = kvm_allocate_vcpu_stack(vm); - vcpu_regs_set(vcpu, ®s); + /* + * Both kvm_get_supported_cpuid() (for legacy VMs) and KVM_TDX_GET_CPUID + * (for TDX VMs) return VM-scoped CPUID. e.g. the APIC ID isn't + * populated per vCPU. This is fine because KVM selftests don't + * currently test CPUID topology enumeration. + */ + if (is_tdx_vm(vm)) { + tdx_vcpu_init(vm, vcpu); + } else { + vcpu_init_cpuid(vcpu, kvm_get_supported_cpuid()); + + vcpu_init_sregs(vm, vcpu); + vcpu_init_xcrs(vm, vcpu); + + /* Setup guest general purpose registers */ + vcpu_regs_get(vcpu, ®s); + regs.rflags = regs.rflags | 0x2; + regs.rsp = kvm_allocate_vcpu_stack(vm); + vcpu_regs_set(vcpu, ®s); + } /* Setup the MP state */ mp_state.mp_state = 0; -- 2.56.0.rc1.315.gc6ed9934b7-goog
