The test calls get_td_vmcall_info from the guest and verifies the expected returned values.
Signed-off-by: Sagi Shahar sagis@google.com --- tools/testing/selftests/kvm/lib/x86_64/tdx.h | 43 +++++++ .../selftests/kvm/x86_64/tdx_vm_tests.c | 107 ++++++++++++++++++ 2 files changed, 150 insertions(+)
diff --git a/tools/testing/selftests/kvm/lib/x86_64/tdx.h b/tools/testing/selftests/kvm/lib/x86_64/tdx.h index a28d15417d3e..39b000118e26 100644 --- a/tools/testing/selftests/kvm/lib/x86_64/tdx.h +++ b/tools/testing/selftests/kvm/lib/x86_64/tdx.h @@ -51,6 +51,7 @@ #define _PAGE_RW (1UL<<1) /* writeable */ #define _PAGE_PS (1UL<<7) /* page size bit*/
+#define TDX_GET_TD_VM_CALL_INFO 0x10000 #define TDX_REPORT_FATAL_ERROR 0x10003 #define TDX_INSTRUCTION_IO 30
@@ -232,6 +233,28 @@ static inline void tdvmcall_fatal(uint64_t error_code) tdcall(®s); }
+/* + * Get td vmcall info. + * Used to help request the host VMM enumerate which TDG.VP.VMCALLs are supported. + * Returns return in r10 code and leaf-specific output in r11-r14. + */ +static inline uint64_t tdvmcall_get_td_vmcall_info(uint64_t *r11, uint64_t *r12, + uint64_t *r13, uint64_t *r14) +{ + struct kvm_regs regs; + + memset(®s, 0, sizeof(regs)); + regs.r11 = TDX_GET_TD_VM_CALL_INFO; + regs.r12 = 0; + regs.rcx = 0x1C00; + tdcall(®s); + *r11 = regs.r11; + *r12 = regs.r12; + *r13 = regs.r13; + *r14 = regs.r14; + return regs.r10; +} + /* * Reports a 32 bit value from the guest to user space using a TDVM IO call. * Data is reported on port TDX_DATA_REPORT_PORT. @@ -244,6 +267,26 @@ static inline uint64_t tdvm_report_to_user_space(uint32_t data) return tdvmcall_io(TDX_DATA_REPORT_PORT, /*size=*/4, TDX_IO_WRITE, &data_64); }
+/* + * Reports a 64 bit value from the guest to user space using a TDVM IO call. + * Data is reported on port TDX_DATA_REPORT_PORT. + * Data is sent to host in 2 calls. LSB is sent (and needs to be read) first. + */ +static inline uint64_t tdvm_report_64bit_to_user_space(uint64_t data) +{ + uint64_t err; + uint64_t data_lo = data & 0xFFFFFFFF; + uint64_t data_hi = (data >> 32) & 0xFFFFFFFF; + + err = tdvmcall_io(TDX_DATA_REPORT_PORT, /*size=*/4, TDX_IO_WRITE, + &data_lo); + if (err) + return err; + + return tdvmcall_io(TDX_DATA_REPORT_PORT, /*size=*/4, TDX_IO_WRITE, + &data_hi); +} + #define TDX_FUNCTION_SIZE(name) ((uint64_t)&__stop_sec_ ## name -\ (uint64_t)&__start_sec_ ## name) \
diff --git a/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c b/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c index 3f51f936ea5a..cf8260db1f5b 100644 --- a/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c +++ b/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c @@ -53,6 +53,25 @@ (VCPU)->run->system_event.data[1]); \ } while (0)
+static uint64_t read_64bit_from_guest(struct kvm_vcpu *vcpu, uint64_t port) +{ + uint32_t lo, hi; + uint64_t res; + + CHECK_IO(vcpu, port, 4, TDX_IO_WRITE); + lo = *(uint32_t *)((void *)vcpu->run + vcpu->run->io.data_offset); + + vcpu_run(vcpu); + + CHECK_IO(vcpu, port, 4, TDX_IO_WRITE); + hi = *(uint32_t *)((void *)vcpu->run + vcpu->run->io.data_offset); + + res = hi; + res = (res << 32) | lo; + return res; +} + + /* * There might be multiple tests we are running and if one test fails, it will * prevent the subsequent tests to run due to how tests are failing with @@ -383,6 +402,93 @@ void verify_td_cpuid(void) printf("\t ... PASSED\n"); }
+/* + * Verifies get_td_vmcall_info functionality. + */ +TDX_GUEST_FUNCTION(guest_code_get_td_vmcall_info) +{ + uint64_t err; + uint64_t r11, r12, r13, r14; + + err = tdvmcall_get_td_vmcall_info(&r11, &r12, &r13, &r14); + if (err) + tdvmcall_fatal(err); + + err = tdvm_report_64bit_to_user_space(r11); + if (err) + tdvmcall_fatal(err); + + err = tdvm_report_64bit_to_user_space(r12); + if (err) + tdvmcall_fatal(err); + + err = tdvm_report_64bit_to_user_space(r13); + if (err) + tdvmcall_fatal(err); + + err = tdvm_report_64bit_to_user_space(r14); + if (err) + tdvmcall_fatal(err); + + tdvmcall_success(); +} + +void verify_get_td_vmcall_info(void) +{ + struct kvm_vcpu *vcpu; + struct kvm_vm *vm; + uint64_t r11, r12, r13, r14; + + printf("Verifying TD get vmcall info:\n"); + /* Create a TD VM with no memory.*/ + vm = vm_create_tdx(); + + /* Allocate TD guest memory and initialize the TD.*/ + initialize_td(vm); + + /* Initialize the TD vcpu and copy the test code to the guest memory.*/ + vcpu = vm_vcpu_add_tdx(vm, 0); + + /* Setup and initialize VM memory */ + prepare_source_image(vm, guest_code_get_td_vmcall_info, + TDX_FUNCTION_SIZE(guest_code_get_td_vmcall_info), + 0); + finalize_td_memory(vm); + + /* Wait for guest to report r11 value */ + vcpu_run(vcpu); + CHECK_GUEST_FAILURE(vcpu); + r11 = read_64bit_from_guest(vcpu, TDX_DATA_REPORT_PORT); + + /* Wait for guest to report r12 value */ + vcpu_run(vcpu); + CHECK_GUEST_FAILURE(vcpu); + r12 = read_64bit_from_guest(vcpu, TDX_DATA_REPORT_PORT); + + /* Wait for guest to report r13 value */ + vcpu_run(vcpu); + CHECK_GUEST_FAILURE(vcpu); + r13 = read_64bit_from_guest(vcpu, TDX_DATA_REPORT_PORT); + + /* Wait for guest to report r14 value */ + vcpu_run(vcpu); + CHECK_GUEST_FAILURE(vcpu); + r14 = read_64bit_from_guest(vcpu, TDX_DATA_REPORT_PORT); + + ASSERT_EQ(r11, 0); + ASSERT_EQ(r12, 0); + ASSERT_EQ(r13, 0); + ASSERT_EQ(r14, 0); + + /* Wait for guest to complete execution */ + vcpu_run(vcpu); + CHECK_GUEST_FAILURE(vcpu); + CHECK_GUEST_COMPLETION(vcpu); + + kvm_vm_free(vm); + printf("\t ... PASSED\n"); +} + int main(int argc, char **argv) { if (!is_tdx_enabled()) { @@ -394,6 +500,7 @@ int main(int argc, char **argv) run_in_new_process(&verify_report_fatal_error); run_in_new_process(&verify_td_ioexit); run_in_new_process(&verify_td_cpuid); + run_in_new_process(&verify_get_td_vmcall_info);
return 0; }