KVM_TDX_INIT_VM needs to be called after KVM_CREATE_VM and before creating any VCPUs, thus before KVM_SET_CPUID2. KVM_TDX_INIT_VM accepts the CPUID values directly.
Since KVM_GET_CPUID2 can't be used at this point, calculate the CPUID values manually by using kvm_get_supported_cpuid() and filter the returned CPUIDs against the supported CPUID values read from the TDX module.
Co-developed-by: Isaku Yamahata isaku.yamahata@intel.com Signed-off-by: Isaku Yamahata isaku.yamahata@intel.com Co-developed-by: Rick Edgecombe rick.p.edgecombe@intel.com Signed-off-by: Rick Edgecombe rick.p.edgecombe@intel.com Signed-off-by: Sagi Shahar sagis@google.com --- .../selftests/kvm/include/x86/tdx/tdx_util.h | 54 +++++++ .../selftests/kvm/lib/x86/tdx/tdx_util.c | 132 ++++++++++++++++++ 2 files changed, 186 insertions(+)
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 dafdc7e46abe..a2509959c7ce 100644 --- a/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h +++ b/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h @@ -11,6 +11,60 @@ static inline bool is_tdx_vm(struct kvm_vm *vm) return vm->type == KVM_X86_TDX_VM; }
+/* + * TDX ioctls + */ + +#define __vm_tdx_vm_ioctl(vm, cmd, metadata, arg) \ +({ \ + int r; \ + \ + union { \ + struct kvm_tdx_cmd c; \ + unsigned long raw; \ + } tdx_cmd = { .c = { \ + .id = (cmd), \ + .flags = (uint32_t)(metadata), \ + .data = (uint64_t)(arg), \ + } }; \ + \ + r = __vm_ioctl(vm, KVM_MEMORY_ENCRYPT_OP, &tdx_cmd.raw); \ + r ?: tdx_cmd.c.hw_error; \ +}) + +#define vm_tdx_vm_ioctl(vm, cmd, flags, arg) \ +({ \ + int ret = __vm_tdx_vm_ioctl(vm, cmd, flags, arg); \ + \ + __TEST_ASSERT_VM_VCPU_IOCTL(!ret, #cmd, ret, vm); \ +}) + +#define __vm_tdx_vcpu_ioctl(vcpu, cmd, metadata, arg) \ +({ \ + int r; \ + \ + union { \ + struct kvm_tdx_cmd c; \ + unsigned long raw; \ + } tdx_cmd = { .c = { \ + .id = (cmd), \ + .flags = (uint32_t)(metadata), \ + .data = (uint64_t)(arg), \ + } }; \ + \ + r = __vcpu_ioctl(vcpu, KVM_MEMORY_ENCRYPT_OP, &tdx_cmd.raw); \ + r ?: tdx_cmd.c.hw_error; \ +}) + +#define vm_tdx_vcpu_ioctl(vcpu, cmd, flags, arg) \ +({ \ + int ret = __vm_tdx_vcpu_ioctl(vcpu, cmd, flags, arg); \ + \ + __TEST_ASSERT_VM_VCPU_IOCTL(!ret, #cmd, ret, (vcpu)->vm); \ +}) + +void vm_tdx_init_vm(struct kvm_vm *vm, uint64_t attributes); + void vm_tdx_setup_boot_code_region(struct kvm_vm *vm); void vm_tdx_setup_boot_parameters_region(struct kvm_vm *vm, uint32_t nr_runnable_vcpus); void vm_tdx_load_common_boot_parameters(struct kvm_vm *vm); diff --git a/tools/testing/selftests/kvm/lib/x86/tdx/tdx_util.c b/tools/testing/selftests/kvm/lib/x86/tdx/tdx_util.c index ff61333bc848..aa0cb6c2205b 100644 --- a/tools/testing/selftests/kvm/lib/x86/tdx/tdx_util.c +++ b/tools/testing/selftests/kvm/lib/x86/tdx/tdx_util.c @@ -127,3 +127,135 @@ void vm_tdx_set_vcpu_entry_point(struct kvm_vcpu *vcpu, void *guest_code)
vcpu_params->guest_code = (uint64_t)guest_code; } + +static struct kvm_tdx_capabilities *tdx_read_capabilities(struct kvm_vm *vm) +{ + struct kvm_tdx_capabilities *tdx_cap = NULL; + int nr_cpuid_configs = 4; + int rc = -1; + int i; + + do { + nr_cpuid_configs *= 2; + + tdx_cap = realloc(tdx_cap, sizeof(*tdx_cap) + + sizeof(tdx_cap->cpuid) + + (sizeof(struct kvm_cpuid_entry2) * nr_cpuid_configs)); + TEST_ASSERT(tdx_cap, + "Could not allocate memory for tdx capability nr_cpuid_configs %d\n", + nr_cpuid_configs); + + tdx_cap->cpuid.nent = nr_cpuid_configs; + rc = __vm_tdx_vm_ioctl(vm, KVM_TDX_CAPABILITIES, 0, tdx_cap); + } while (rc < 0 && errno == E2BIG); + + TEST_ASSERT(rc == 0, "KVM_TDX_CAPABILITIES failed: %d %d", + rc, errno); + + pr_debug("tdx_cap: supported_attrs: 0x%016llx\n" + "tdx_cap: supported_xfam 0x%016llx\n", + tdx_cap->supported_attrs, tdx_cap->supported_xfam); + + for (i = 0; i < tdx_cap->cpuid.nent; i++) { + const struct kvm_cpuid_entry2 *config = &tdx_cap->cpuid.entries[i]; + + pr_debug("cpuid config[%d]: leaf 0x%x sub_leaf 0x%x eax 0x%08x ebx 0x%08x ecx 0x%08x edx 0x%08x\n", + i, config->function, config->index, + config->eax, config->ebx, config->ecx, config->edx); + } + + return tdx_cap; +} + +static struct kvm_cpuid_entry2 *tdx_find_cpuid_config(struct kvm_tdx_capabilities *cap, + uint32_t leaf, uint32_t sub_leaf) +{ + struct kvm_cpuid_entry2 *config; + uint32_t i; + + for (i = 0; i < cap->cpuid.nent; i++) { + config = &cap->cpuid.entries[i]; + + if (config->function == leaf && config->index == sub_leaf) + return config; + } + + return NULL; +} + +/* + * Filter CPUID based on TDX supported capabilities + * + * Input Args: + * vm - Virtual Machine + * cpuid_data - CPUID fileds to filter + * + * Output Args: None + * + * Return: None + * + * For each CPUID leaf, filter out non-supported bits based on the capabilities reported + * by the TDX module + */ +static void vm_tdx_filter_cpuid(struct kvm_vm *vm, + struct kvm_cpuid2 *cpuid_data) +{ + struct kvm_tdx_capabilities *tdx_cap; + struct kvm_cpuid_entry2 *config; + struct kvm_cpuid_entry2 *e; + int i; + + tdx_cap = tdx_read_capabilities(vm); + + i = 0; + while (i < cpuid_data->nent) { + e = cpuid_data->entries + i; + config = tdx_find_cpuid_config(tdx_cap, e->function, e->index); + + if (!config) { + int left = cpuid_data->nent - i - 1; + + if (left > 0) + memmove(cpuid_data->entries + i, + cpuid_data->entries + i + 1, + sizeof(*cpuid_data->entries) * left); + cpuid_data->nent--; + continue; + } + + e->eax &= config->eax; + e->ebx &= config->ebx; + e->ecx &= config->ecx; + e->edx &= config->edx; + + i++; + } + + free(tdx_cap); +} + +void vm_tdx_init_vm(struct kvm_vm *vm, uint64_t attributes) +{ + struct kvm_tdx_init_vm *init_vm; + const struct kvm_cpuid2 *tmp; + struct kvm_cpuid2 *cpuid; + + tmp = kvm_get_supported_cpuid(); + + cpuid = allocate_kvm_cpuid2(MAX_NR_CPUID_ENTRIES); + memcpy(cpuid, tmp, kvm_cpuid2_size(tmp->nent)); + vm_tdx_filter_cpuid(vm, cpuid); + + init_vm = calloc(1, sizeof(*init_vm) + + sizeof(init_vm->cpuid.entries[0]) * cpuid->nent); + TEST_ASSERT(init_vm, "init_vm allocation failed"); + + memcpy(&init_vm->cpuid, cpuid, kvm_cpuid2_size(cpuid->nent)); + free(cpuid); + + init_vm->attributes = attributes; + + vm_tdx_vm_ioctl(vm, KVM_TDX_INIT_VM, 0, init_vm); + + free(init_vm); +}