[RFC,v5,08/29] KVM: selftests: TDX: Add TDX lifecycle test

Message ID 20231212204647.2170650-9-sagis@google.com
State New
Headers
Series TDX KVM selftests |

Commit Message

Sagi Shahar Dec. 12, 2023, 8:46 p.m. UTC
  From: Erdem Aktas <erdemaktas@google.com>

Adding a test to verify TDX lifecycle by creating a TD and running a
dummy TDG.VP.VMCALL <Instruction.IO> inside it.

Signed-off-by: Erdem Aktas <erdemaktas@google.com>
Signed-off-by: Ryan Afranji <afranji@google.com>
Signed-off-by: Sagi Shahar <sagis@google.com>
Co-developed-by: Ackerley Tng <ackerleytng@google.com>
Signed-off-by: Ackerley Tng <ackerleytng@google.com>
---
 tools/testing/selftests/kvm/Makefile          |  4 +
 .../selftests/kvm/include/x86_64/tdx/tdcall.h | 35 ++++++++
 .../selftests/kvm/include/x86_64/tdx/tdx.h    | 12 +++
 .../kvm/include/x86_64/tdx/test_util.h        | 52 +++++++++++
 .../selftests/kvm/lib/x86_64/tdx/tdcall.S     | 90 +++++++++++++++++++
 .../selftests/kvm/lib/x86_64/tdx/tdx.c        | 27 ++++++
 .../selftests/kvm/lib/x86_64/tdx/tdx_util.c   |  1 +
 .../selftests/kvm/lib/x86_64/tdx/test_util.c  | 34 +++++++
 .../selftests/kvm/x86_64/tdx_vm_tests.c       | 45 ++++++++++
 9 files changed, 300 insertions(+)
 create mode 100644 tools/testing/selftests/kvm/include/x86_64/tdx/tdcall.h
 create mode 100644 tools/testing/selftests/kvm/include/x86_64/tdx/tdx.h
 create mode 100644 tools/testing/selftests/kvm/include/x86_64/tdx/test_util.h
 create mode 100644 tools/testing/selftests/kvm/lib/x86_64/tdx/tdcall.S
 create mode 100644 tools/testing/selftests/kvm/lib/x86_64/tdx/tdx.c
 create mode 100644 tools/testing/selftests/kvm/lib/x86_64/tdx/test_util.c
 create mode 100644 tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c
  

Comments

Chen Yu Feb. 23, 2024, 1:55 a.m. UTC | #1
Hi Sagi,

On 2023-12-12 at 12:46:23 -0800, Sagi Shahar wrote:
> From: Erdem Aktas <erdemaktas@google.com>
> 
> Adding a test to verify TDX lifecycle by creating a TD and running a
> dummy TDG.VP.VMCALL <Instruction.IO> inside it.
> 
> Signed-off-by: Erdem Aktas <erdemaktas@google.com>
> Signed-off-by: Ryan Afranji <afranji@google.com>
> Signed-off-by: Sagi Shahar <sagis@google.com>
> Co-developed-by: Ackerley Tng <ackerleytng@google.com>
> Signed-off-by: Ackerley Tng <ackerleytng@google.com>
> ---
>  tools/testing/selftests/kvm/Makefile          |  4 +
>  .../selftests/kvm/include/x86_64/tdx/tdcall.h | 35 ++++++++
>  .../selftests/kvm/include/x86_64/tdx/tdx.h    | 12 +++
>  .../kvm/include/x86_64/tdx/test_util.h        | 52 +++++++++++
>  .../selftests/kvm/lib/x86_64/tdx/tdcall.S     | 90 +++++++++++++++++++
>  .../selftests/kvm/lib/x86_64/tdx/tdx.c        | 27 ++++++
>  .../selftests/kvm/lib/x86_64/tdx/tdx_util.c   |  1 +
>  .../selftests/kvm/lib/x86_64/tdx/test_util.c  | 34 +++++++
>  .../selftests/kvm/x86_64/tdx_vm_tests.c       | 45 ++++++++++
>  9 files changed, 300 insertions(+)
>  create mode 100644 tools/testing/selftests/kvm/include/x86_64/tdx/tdcall.h
>  create mode 100644 tools/testing/selftests/kvm/include/x86_64/tdx/tdx.h
>  create mode 100644 tools/testing/selftests/kvm/include/x86_64/tdx/test_util.h
>  create mode 100644 tools/testing/selftests/kvm/lib/x86_64/tdx/tdcall.S
>  create mode 100644 tools/testing/selftests/kvm/lib/x86_64/tdx/tdx.c
>  create mode 100644 tools/testing/selftests/kvm/lib/x86_64/tdx/test_util.c
>  create mode 100644 tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c
> 
> diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
> index a35150ab855f..80d4a50eeb9f 100644
> --- a/tools/testing/selftests/kvm/Makefile
> +++ b/tools/testing/selftests/kvm/Makefile
> @@ -52,6 +52,9 @@ LIBKVM_x86_64 += lib/x86_64/vmx.c
>  LIBKVM_x86_64 += lib/x86_64/sev.c
>  LIBKVM_x86_64 += lib/x86_64/tdx/tdx_util.c
>  LIBKVM_x86_64 += lib/x86_64/tdx/td_boot.S
> +LIBKVM_x86_64 += lib/x86_64/tdx/tdcall.S
> +LIBKVM_x86_64 += lib/x86_64/tdx/tdx.c
> +LIBKVM_x86_64 += lib/x86_64/tdx/test_util.c
>  
>  LIBKVM_aarch64 += lib/aarch64/gic.c
>  LIBKVM_aarch64 += lib/aarch64/gic_v3.c
> @@ -152,6 +155,7 @@ TEST_GEN_PROGS_x86_64 += set_memory_region_test
>  TEST_GEN_PROGS_x86_64 += steal_time
>  TEST_GEN_PROGS_x86_64 += kvm_binary_stats_test
>  TEST_GEN_PROGS_x86_64 += system_counter_offset_test
> +TEST_GEN_PROGS_x86_64 += x86_64/tdx_vm_tests
>  
>  # Compiled outputs used by test targets
>  TEST_GEN_PROGS_EXTENDED_x86_64 += x86_64/nx_huge_pages_test
> diff --git a/tools/testing/selftests/kvm/include/x86_64/tdx/tdcall.h b/tools/testing/selftests/kvm/include/x86_64/tdx/tdcall.h
> new file mode 100644
> index 000000000000..78001bfec9c8
> --- /dev/null
> +++ b/tools/testing/selftests/kvm/include/x86_64/tdx/tdcall.h
> @@ -0,0 +1,35 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/* Adapted from arch/x86/include/asm/shared/tdx.h */
> +
> +#ifndef SELFTESTS_TDX_TDCALL_H
> +#define SELFTESTS_TDX_TDCALL_H
> +
> +#include <linux/bits.h>
> +#include <linux/types.h>
> +
> +#define TDG_VP_VMCALL_INSTRUCTION_IO_READ 0
> +#define TDG_VP_VMCALL_INSTRUCTION_IO_WRITE 1
> +
> +#define TDX_HCALL_HAS_OUTPUT BIT(0)
> +
> +#define TDX_HYPERCALL_STANDARD 0
> +
> +/*
> + * Used in __tdx_hypercall() to pass down and get back registers' values of
> + * the TDCALL instruction when requesting services from the VMM.
> + *
> + * This is a software only structure and not part of the TDX module/VMM ABI.
> + */
> +struct tdx_hypercall_args {
> +	u64 r10;
> +	u64 r11;
> +	u64 r12;
> +	u64 r13;
> +	u64 r14;
> +	u64 r15;
> +};
> +
> +/* Used to request services from the VMM */
> +u64 __tdx_hypercall(struct tdx_hypercall_args *args, unsigned long flags);
> +
> +#endif // SELFTESTS_TDX_TDCALL_H
> diff --git a/tools/testing/selftests/kvm/include/x86_64/tdx/tdx.h b/tools/testing/selftests/kvm/include/x86_64/tdx/tdx.h
> new file mode 100644
> index 000000000000..a7161efe4ee2
> --- /dev/null
> +++ b/tools/testing/selftests/kvm/include/x86_64/tdx/tdx.h
> @@ -0,0 +1,12 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +#ifndef SELFTEST_TDX_TDX_H
> +#define SELFTEST_TDX_TDX_H
> +
> +#include <stdint.h>
> +
> +#define TDG_VP_VMCALL_INSTRUCTION_IO 30
> +
> +uint64_t tdg_vp_vmcall_instruction_io(uint64_t port, uint64_t size,
> +				      uint64_t write, uint64_t *data);
> +
> +#endif // SELFTEST_TDX_TDX_H
> diff --git a/tools/testing/selftests/kvm/include/x86_64/tdx/test_util.h b/tools/testing/selftests/kvm/include/x86_64/tdx/test_util.h
> new file mode 100644
> index 000000000000..b570b6d978ff
> --- /dev/null
> +++ b/tools/testing/selftests/kvm/include/x86_64/tdx/test_util.h
> @@ -0,0 +1,52 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +#ifndef SELFTEST_TDX_TEST_UTIL_H
> +#define SELFTEST_TDX_TEST_UTIL_H
> +
> +#include <stdbool.h>
> +
> +#include "tdcall.h"
> +
> +#define TDX_TEST_SUCCESS_PORT 0x30
> +#define TDX_TEST_SUCCESS_SIZE 4
> +
> +/**
> + * Assert that tdx_test_success() was called in the guest.
> + */
> +#define TDX_TEST_ASSERT_SUCCESS(VCPU)					\
> +	(TEST_ASSERT(							\
> +		((VCPU)->run->exit_reason == KVM_EXIT_IO) &&		\
> +		((VCPU)->run->io.port == TDX_TEST_SUCCESS_PORT) &&	\
> +		((VCPU)->run->io.size == TDX_TEST_SUCCESS_SIZE) &&	\
> +		((VCPU)->run->io.direction ==				\
> +			TDG_VP_VMCALL_INSTRUCTION_IO_WRITE),		\
> +		"Unexpected exit values while waiting for test completion: %u (%s) %d %d %d\n", \
> +		(VCPU)->run->exit_reason,				\
> +		exit_reason_str((VCPU)->run->exit_reason),		\
> +		(VCPU)->run->io.port, (VCPU)->run->io.size,		\
> +		(VCPU)->run->io.direction))
> +
> +/**
> + * Run a test in a new process.
> + *
> + * 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
> + * TEST_ASSERT function. The run_in_new_process function will run a test in a
> + * new process context and wait for it to finish or fail to prevent TEST_ASSERT
> + * to kill the main testing process.
> + */
> +void run_in_new_process(void (*func)(void));
> +
> +/**
> + * Verify that the TDX is supported by KVM.
> + */
> +bool is_tdx_enabled(void);
> +
> +/**
> + * Report test success to userspace.
> + *
> + * Use TDX_TEST_ASSERT_SUCCESS() to assert that this function was called in the
> + * guest.
> + */
> +void tdx_test_success(void);
> +
> +#endif // SELFTEST_TDX_TEST_UTIL_H
> diff --git a/tools/testing/selftests/kvm/lib/x86_64/tdx/tdcall.S b/tools/testing/selftests/kvm/lib/x86_64/tdx/tdcall.S
> new file mode 100644
> index 000000000000..df9c1ed4bb2d
> --- /dev/null
> +++ b/tools/testing/selftests/kvm/lib/x86_64/tdx/tdcall.S
> @@ -0,0 +1,90 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/* Adapted from arch/x86/coco/tdx/tdcall.S */
> +
> +#define TDX_HYPERCALL_r10 0 /* offsetof(struct tdx_hypercall_args, r10) */
> +#define TDX_HYPERCALL_r11 8 /* offsetof(struct tdx_hypercall_args, r11) */
> +#define TDX_HYPERCALL_r12 16 /* offsetof(struct tdx_hypercall_args, r12) */
> +#define TDX_HYPERCALL_r13 24 /* offsetof(struct tdx_hypercall_args, r13) */
> +#define TDX_HYPERCALL_r14 32 /* offsetof(struct tdx_hypercall_args, r14) */
> +#define TDX_HYPERCALL_r15 40 /* offsetof(struct tdx_hypercall_args, r15) */
> +
> +/*
> + * Bitmasks of exposed registers (with VMM).
> + */
> +#define TDX_R10 0x400
> +#define TDX_R11 0x800
> +#define TDX_R12 0x1000
> +#define TDX_R13 0x2000
> +#define TDX_R14 0x4000
> +#define TDX_R15 0x8000
> +
> +#define TDX_HCALL_HAS_OUTPUT 0x1
> +
> +/*
> + * These registers are clobbered to hold arguments for each
> + * TDVMCALL. They are safe to expose to the VMM.
> + * Each bit in this mask represents a register ID. Bit field
> + * details can be found in TDX GHCI specification, section
> + * titled "TDCALL [TDG.VP.VMCALL] leaf".
> + */
> +#define TDVMCALL_EXPOSE_REGS_MASK	( TDX_R10 | TDX_R11 | \
> +					  TDX_R12 | TDX_R13 | \
> +					  TDX_R14 | TDX_R15 )
> +
> +.code64
> +.section .text
> +
> +.globl __tdx_hypercall
> +.type __tdx_hypercall, @function
> +__tdx_hypercall:
> +	/* Set up stack frame */
> +	push %rbp
> +	movq %rsp, %rbp
> +
> +	/* Save callee-saved GPRs as mandated by the x86_64 ABI */
> +	push %r15
> +	push %r14
> +	push %r13
> +	push %r12
> +
> +	/* Mangle function call ABI into TDCALL ABI: */
> +	/* Set TDCALL leaf ID (TDVMCALL (0)) in RAX */
> +	xor %eax, %eax
> +
> +	/* Copy hypercall registers from arg struct: */
> +	movq TDX_HYPERCALL_r10(%rdi), %r10
> +	movq TDX_HYPERCALL_r11(%rdi), %r11
> +	movq TDX_HYPERCALL_r12(%rdi), %r12
> +	movq TDX_HYPERCALL_r13(%rdi), %r13
> +	movq TDX_HYPERCALL_r14(%rdi), %r14
> +	movq TDX_HYPERCALL_r15(%rdi), %r15
> +
> +	movl $TDVMCALL_EXPOSE_REGS_MASK, %ecx
> +
> +	tdcall
> +
> +	/* TDVMCALL leaf return code is in R10 */
> +	movq %r10, %rax
> +
> +	/* Copy hypercall result registers to arg struct if needed */
> +	testq $TDX_HCALL_HAS_OUTPUT, %rsi
> +	jz .Lout
> +
> +	movq %r10, TDX_HYPERCALL_r10(%rdi)
> +	movq %r11, TDX_HYPERCALL_r11(%rdi)
> +	movq %r12, TDX_HYPERCALL_r12(%rdi)
> +	movq %r13, TDX_HYPERCALL_r13(%rdi)
> +	movq %r14, TDX_HYPERCALL_r14(%rdi)
> +	movq %r15, TDX_HYPERCALL_r15(%rdi)
> +.Lout:
> +	/* Restore callee-saved GPRs as mandated by the x86_64 ABI */
> +	pop %r12
> +	pop %r13
> +	pop %r14
> +	pop %r15
> +
> +	pop %rbp
> +	ret
> +
> +/* Disable executable stack */
> +.section .note.GNU-stack,"",%progbits
> diff --git a/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx.c b/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx.c
> new file mode 100644
> index 000000000000..c2414523487a
> --- /dev/null
> +++ b/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx.c
> @@ -0,0 +1,27 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +
> +#include "tdx/tdcall.h"
> +#include "tdx/tdx.h"
> +
> +uint64_t tdg_vp_vmcall_instruction_io(uint64_t port, uint64_t size,
> +				      uint64_t write, uint64_t *data)
> +{
> +	uint64_t ret;
> +	struct tdx_hypercall_args args = {
> +		.r10 = TDX_HYPERCALL_STANDARD,
> +		.r11 = TDG_VP_VMCALL_INSTRUCTION_IO,
> +		.r12 = size,
> +		.r13 = write,
> +		.r14 = port,
> +	};
> +
> +	if (write)
> +		args.r15 = *data;
> +
> +	ret = __tdx_hypercall(&args, write ? 0 : TDX_HCALL_HAS_OUTPUT);
> +
> +	if (!write)
> +		*data = args.r11;
> +
> +	return ret;
> +}
> diff --git a/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx_util.c b/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx_util.c
> index 063ff486fb86..b302060049d5 100644
> --- a/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx_util.c
> +++ b/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx_util.c
> @@ -224,6 +224,7 @@ static void tdx_enable_capabilities(struct kvm_vm *vm)
>  		      KVM_X2APIC_API_USE_32BIT_IDS |
>  			      KVM_X2APIC_API_DISABLE_BROADCAST_QUIRK);
>  	vm_enable_cap(vm, KVM_CAP_SPLIT_IRQCHIP, 24);
> +	vm_enable_cap(vm, KVM_CAP_MAX_VCPUS, 512);
>  }
>  
>  static void tdx_configure_memory_encryption(struct kvm_vm *vm)
> diff --git a/tools/testing/selftests/kvm/lib/x86_64/tdx/test_util.c b/tools/testing/selftests/kvm/lib/x86_64/tdx/test_util.c
> new file mode 100644
> index 000000000000..6905d0ca3877
> --- /dev/null
> +++ b/tools/testing/selftests/kvm/lib/x86_64/tdx/test_util.c
> @@ -0,0 +1,34 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +
> +#include <stdbool.h>
> +#include <stdint.h>
> +#include <stdlib.h>
> +#include <sys/wait.h>
> +#include <unistd.h>
> +
> +#include "kvm_util_base.h"
> +#include "tdx/tdx.h"
> +#include "tdx/test_util.h"
> +
> +void run_in_new_process(void (*func)(void))
> +{
> +	if (fork() == 0) {
> +		func();
> +		exit(0);
> +	}
> +	wait(NULL);
> +}
> +
> +bool is_tdx_enabled(void)
> +{
> +	return !!(kvm_check_cap(KVM_CAP_VM_TYPES) & BIT(KVM_X86_TDX_VM));
> +}
> +
> +void tdx_test_success(void)
> +{
> +	uint64_t code = 0;
> +
> +	tdg_vp_vmcall_instruction_io(TDX_TEST_SUCCESS_PORT,
> +				     TDX_TEST_SUCCESS_SIZE,
> +				     TDG_VP_VMCALL_INSTRUCTION_IO_WRITE, &code);
> +}
> diff --git a/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c b/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c
> new file mode 100644
> index 000000000000..a18d1c9d6026
> --- /dev/null
> +++ b/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c
> @@ -0,0 +1,45 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +
> +#include <signal.h>
> +#include "kvm_util_base.h"
> +#include "tdx/tdx_util.h"
> +#include "tdx/test_util.h"
> +#include "test_util.h"
> +
> +void guest_code_lifecycle(void)
> +{
> +	tdx_test_success();
> +}
> +
> +void verify_td_lifecycle(void)
> +{
> +	struct kvm_vm *vm;
> +	struct kvm_vcpu *vcpu;
> +
> +	vm = td_create();
> +	td_initialize(vm, VM_MEM_SRC_ANONYMOUS, 0);

From a user point of view, this lifecycle test is very useful
to me for vm creation/destruction time test, and I believe you
have an enhanced version to specify the memory size. May I know if
there is any plan to add that part too? And maybe allow the user
to customize the memory size rather than a fixed size.

thanks,
Chenyu
  
Yan Zhao March 1, 2024, 4:58 a.m. UTC | #2
> diff --git a/tools/testing/selftests/kvm/lib/x86_64/tdx/tdcall.S b/tools/testing/selftests/kvm/lib/x86_64/tdx/tdcall.S
> new file mode 100644
> index 000000000000..df9c1ed4bb2d
> --- /dev/null
> +++ b/tools/testing/selftests/kvm/lib/x86_64/tdx/tdcall.S
> @@ -0,0 +1,90 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/* Adapted from arch/x86/coco/tdx/tdcall.S */
> +
> +#define TDX_HYPERCALL_r10 0 /* offsetof(struct tdx_hypercall_args, r10) */
> +#define TDX_HYPERCALL_r11 8 /* offsetof(struct tdx_hypercall_args, r11) */
> +#define TDX_HYPERCALL_r12 16 /* offsetof(struct tdx_hypercall_args, r12) */
> +#define TDX_HYPERCALL_r13 24 /* offsetof(struct tdx_hypercall_args, r13) */
> +#define TDX_HYPERCALL_r14 32 /* offsetof(struct tdx_hypercall_args, r14) */
> +#define TDX_HYPERCALL_r15 40 /* offsetof(struct tdx_hypercall_args, r15) */
> +
> +/*
> + * Bitmasks of exposed registers (with VMM).
> + */
> +#define TDX_R10 0x400
> +#define TDX_R11 0x800
> +#define TDX_R12 0x1000
> +#define TDX_R13 0x2000
> +#define TDX_R14 0x4000
> +#define TDX_R15 0x8000
> +
> +#define TDX_HCALL_HAS_OUTPUT 0x1
> +
> +/*
> + * These registers are clobbered to hold arguments for each
> + * TDVMCALL. They are safe to expose to the VMM.
> + * Each bit in this mask represents a register ID. Bit field
> + * details can be found in TDX GHCI specification, section
> + * titled "TDCALL [TDG.VP.VMCALL] leaf".
> + */
> +#define TDVMCALL_EXPOSE_REGS_MASK	( TDX_R10 | TDX_R11 | \
> +					  TDX_R12 | TDX_R13 | \
> +					  TDX_R14 | TDX_R15 )
> +
> +.code64
> +.section .text
> +
> +.globl __tdx_hypercall
> +.type __tdx_hypercall, @function
> +__tdx_hypercall:
> +	/* Set up stack frame */
> +	push %rbp
> +	movq %rsp, %rbp
> +
> +	/* Save callee-saved GPRs as mandated by the x86_64 ABI */
> +	push %r15
> +	push %r14
> +	push %r13
> +	push %r12
> +
> +	/* Mangle function call ABI into TDCALL ABI: */
> +	/* Set TDCALL leaf ID (TDVMCALL (0)) in RAX */
> +	xor %eax, %eax
> +
> +	/* Copy hypercall registers from arg struct: */
> +	movq TDX_HYPERCALL_r10(%rdi), %r10
> +	movq TDX_HYPERCALL_r11(%rdi), %r11
> +	movq TDX_HYPERCALL_r12(%rdi), %r12
> +	movq TDX_HYPERCALL_r13(%rdi), %r13
> +	movq TDX_HYPERCALL_r14(%rdi), %r14
> +	movq TDX_HYPERCALL_r15(%rdi), %r15
> +
> +	movl $TDVMCALL_EXPOSE_REGS_MASK, %ecx
> +
> +	tdcall
Looks there's a missing of definition for tdcall, and will produce below
error:
lib/x86_64/tdx/tdcall.S:65: Error: no such instruction: `tdcall'

I pulled the code https://github.com/googleprodkernel/linux-cc.git with
branch tdx-selftests-rfc-v5.

Fixed by adding a line in tdcall.S in my side.
#define tdcall          .byte 0x66,0x0f,0x01,0xcc

> +
> +	/* TDVMCALL leaf return code is in R10 */
> +	movq %r10, %rax
> +
> +	/* Copy hypercall result registers to arg struct if needed */
> +	testq $TDX_HCALL_HAS_OUTPUT, %rsi
> +	jz .Lout
> +
> +	movq %r10, TDX_HYPERCALL_r10(%rdi)
> +	movq %r11, TDX_HYPERCALL_r11(%rdi)
> +	movq %r12, TDX_HYPERCALL_r12(%rdi)
> +	movq %r13, TDX_HYPERCALL_r13(%rdi)
> +	movq %r14, TDX_HYPERCALL_r14(%rdi)
> +	movq %r15, TDX_HYPERCALL_r15(%rdi)
> +.Lout:
> +	/* Restore callee-saved GPRs as mandated by the x86_64 ABI */
> +	pop %r12
> +	pop %r13
> +	pop %r14
> +	pop %r15
> +
> +	pop %rbp
> +	ret
> +
> +/* Disable executable stack */
  
Yan Zhao March 1, 2024, 7:36 a.m. UTC | #3
> diff --git a/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx_util.c b/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx_util.c
> index 063ff486fb86..b302060049d5 100644
> --- a/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx_util.c
> +++ b/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx_util.c
> @@ -224,6 +224,7 @@ static void tdx_enable_capabilities(struct kvm_vm *vm)
>  		      KVM_X2APIC_API_USE_32BIT_IDS |
>  			      KVM_X2APIC_API_DISABLE_BROADCAST_QUIRK);
>  	vm_enable_cap(vm, KVM_CAP_SPLIT_IRQCHIP, 24);
> +	vm_enable_cap(vm, KVM_CAP_MAX_VCPUS, 512);

This is not a must for TD life cycle?
Though I know, currently, the selftest will fail without setting this
line, due to TD's default max vcpu count is -1.
But I guess it's an error.
https://lore.kernel.org/all/ZeGC64sAzg4EN3G5@yzhao56-desk.sh.intel.com/
  

Patch

diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index a35150ab855f..80d4a50eeb9f 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -52,6 +52,9 @@  LIBKVM_x86_64 += lib/x86_64/vmx.c
 LIBKVM_x86_64 += lib/x86_64/sev.c
 LIBKVM_x86_64 += lib/x86_64/tdx/tdx_util.c
 LIBKVM_x86_64 += lib/x86_64/tdx/td_boot.S
+LIBKVM_x86_64 += lib/x86_64/tdx/tdcall.S
+LIBKVM_x86_64 += lib/x86_64/tdx/tdx.c
+LIBKVM_x86_64 += lib/x86_64/tdx/test_util.c
 
 LIBKVM_aarch64 += lib/aarch64/gic.c
 LIBKVM_aarch64 += lib/aarch64/gic_v3.c
@@ -152,6 +155,7 @@  TEST_GEN_PROGS_x86_64 += set_memory_region_test
 TEST_GEN_PROGS_x86_64 += steal_time
 TEST_GEN_PROGS_x86_64 += kvm_binary_stats_test
 TEST_GEN_PROGS_x86_64 += system_counter_offset_test
+TEST_GEN_PROGS_x86_64 += x86_64/tdx_vm_tests
 
 # Compiled outputs used by test targets
 TEST_GEN_PROGS_EXTENDED_x86_64 += x86_64/nx_huge_pages_test
diff --git a/tools/testing/selftests/kvm/include/x86_64/tdx/tdcall.h b/tools/testing/selftests/kvm/include/x86_64/tdx/tdcall.h
new file mode 100644
index 000000000000..78001bfec9c8
--- /dev/null
+++ b/tools/testing/selftests/kvm/include/x86_64/tdx/tdcall.h
@@ -0,0 +1,35 @@ 
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Adapted from arch/x86/include/asm/shared/tdx.h */
+
+#ifndef SELFTESTS_TDX_TDCALL_H
+#define SELFTESTS_TDX_TDCALL_H
+
+#include <linux/bits.h>
+#include <linux/types.h>
+
+#define TDG_VP_VMCALL_INSTRUCTION_IO_READ 0
+#define TDG_VP_VMCALL_INSTRUCTION_IO_WRITE 1
+
+#define TDX_HCALL_HAS_OUTPUT BIT(0)
+
+#define TDX_HYPERCALL_STANDARD 0
+
+/*
+ * Used in __tdx_hypercall() to pass down and get back registers' values of
+ * the TDCALL instruction when requesting services from the VMM.
+ *
+ * This is a software only structure and not part of the TDX module/VMM ABI.
+ */
+struct tdx_hypercall_args {
+	u64 r10;
+	u64 r11;
+	u64 r12;
+	u64 r13;
+	u64 r14;
+	u64 r15;
+};
+
+/* Used to request services from the VMM */
+u64 __tdx_hypercall(struct tdx_hypercall_args *args, unsigned long flags);
+
+#endif // SELFTESTS_TDX_TDCALL_H
diff --git a/tools/testing/selftests/kvm/include/x86_64/tdx/tdx.h b/tools/testing/selftests/kvm/include/x86_64/tdx/tdx.h
new file mode 100644
index 000000000000..a7161efe4ee2
--- /dev/null
+++ b/tools/testing/selftests/kvm/include/x86_64/tdx/tdx.h
@@ -0,0 +1,12 @@ 
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef SELFTEST_TDX_TDX_H
+#define SELFTEST_TDX_TDX_H
+
+#include <stdint.h>
+
+#define TDG_VP_VMCALL_INSTRUCTION_IO 30
+
+uint64_t tdg_vp_vmcall_instruction_io(uint64_t port, uint64_t size,
+				      uint64_t write, uint64_t *data);
+
+#endif // SELFTEST_TDX_TDX_H
diff --git a/tools/testing/selftests/kvm/include/x86_64/tdx/test_util.h b/tools/testing/selftests/kvm/include/x86_64/tdx/test_util.h
new file mode 100644
index 000000000000..b570b6d978ff
--- /dev/null
+++ b/tools/testing/selftests/kvm/include/x86_64/tdx/test_util.h
@@ -0,0 +1,52 @@ 
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef SELFTEST_TDX_TEST_UTIL_H
+#define SELFTEST_TDX_TEST_UTIL_H
+
+#include <stdbool.h>
+
+#include "tdcall.h"
+
+#define TDX_TEST_SUCCESS_PORT 0x30
+#define TDX_TEST_SUCCESS_SIZE 4
+
+/**
+ * Assert that tdx_test_success() was called in the guest.
+ */
+#define TDX_TEST_ASSERT_SUCCESS(VCPU)					\
+	(TEST_ASSERT(							\
+		((VCPU)->run->exit_reason == KVM_EXIT_IO) &&		\
+		((VCPU)->run->io.port == TDX_TEST_SUCCESS_PORT) &&	\
+		((VCPU)->run->io.size == TDX_TEST_SUCCESS_SIZE) &&	\
+		((VCPU)->run->io.direction ==				\
+			TDG_VP_VMCALL_INSTRUCTION_IO_WRITE),		\
+		"Unexpected exit values while waiting for test completion: %u (%s) %d %d %d\n", \
+		(VCPU)->run->exit_reason,				\
+		exit_reason_str((VCPU)->run->exit_reason),		\
+		(VCPU)->run->io.port, (VCPU)->run->io.size,		\
+		(VCPU)->run->io.direction))
+
+/**
+ * Run a test in a new process.
+ *
+ * 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
+ * TEST_ASSERT function. The run_in_new_process function will run a test in a
+ * new process context and wait for it to finish or fail to prevent TEST_ASSERT
+ * to kill the main testing process.
+ */
+void run_in_new_process(void (*func)(void));
+
+/**
+ * Verify that the TDX is supported by KVM.
+ */
+bool is_tdx_enabled(void);
+
+/**
+ * Report test success to userspace.
+ *
+ * Use TDX_TEST_ASSERT_SUCCESS() to assert that this function was called in the
+ * guest.
+ */
+void tdx_test_success(void);
+
+#endif // SELFTEST_TDX_TEST_UTIL_H
diff --git a/tools/testing/selftests/kvm/lib/x86_64/tdx/tdcall.S b/tools/testing/selftests/kvm/lib/x86_64/tdx/tdcall.S
new file mode 100644
index 000000000000..df9c1ed4bb2d
--- /dev/null
+++ b/tools/testing/selftests/kvm/lib/x86_64/tdx/tdcall.S
@@ -0,0 +1,90 @@ 
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Adapted from arch/x86/coco/tdx/tdcall.S */
+
+#define TDX_HYPERCALL_r10 0 /* offsetof(struct tdx_hypercall_args, r10) */
+#define TDX_HYPERCALL_r11 8 /* offsetof(struct tdx_hypercall_args, r11) */
+#define TDX_HYPERCALL_r12 16 /* offsetof(struct tdx_hypercall_args, r12) */
+#define TDX_HYPERCALL_r13 24 /* offsetof(struct tdx_hypercall_args, r13) */
+#define TDX_HYPERCALL_r14 32 /* offsetof(struct tdx_hypercall_args, r14) */
+#define TDX_HYPERCALL_r15 40 /* offsetof(struct tdx_hypercall_args, r15) */
+
+/*
+ * Bitmasks of exposed registers (with VMM).
+ */
+#define TDX_R10 0x400
+#define TDX_R11 0x800
+#define TDX_R12 0x1000
+#define TDX_R13 0x2000
+#define TDX_R14 0x4000
+#define TDX_R15 0x8000
+
+#define TDX_HCALL_HAS_OUTPUT 0x1
+
+/*
+ * These registers are clobbered to hold arguments for each
+ * TDVMCALL. They are safe to expose to the VMM.
+ * Each bit in this mask represents a register ID. Bit field
+ * details can be found in TDX GHCI specification, section
+ * titled "TDCALL [TDG.VP.VMCALL] leaf".
+ */
+#define TDVMCALL_EXPOSE_REGS_MASK	( TDX_R10 | TDX_R11 | \
+					  TDX_R12 | TDX_R13 | \
+					  TDX_R14 | TDX_R15 )
+
+.code64
+.section .text
+
+.globl __tdx_hypercall
+.type __tdx_hypercall, @function
+__tdx_hypercall:
+	/* Set up stack frame */
+	push %rbp
+	movq %rsp, %rbp
+
+	/* Save callee-saved GPRs as mandated by the x86_64 ABI */
+	push %r15
+	push %r14
+	push %r13
+	push %r12
+
+	/* Mangle function call ABI into TDCALL ABI: */
+	/* Set TDCALL leaf ID (TDVMCALL (0)) in RAX */
+	xor %eax, %eax
+
+	/* Copy hypercall registers from arg struct: */
+	movq TDX_HYPERCALL_r10(%rdi), %r10
+	movq TDX_HYPERCALL_r11(%rdi), %r11
+	movq TDX_HYPERCALL_r12(%rdi), %r12
+	movq TDX_HYPERCALL_r13(%rdi), %r13
+	movq TDX_HYPERCALL_r14(%rdi), %r14
+	movq TDX_HYPERCALL_r15(%rdi), %r15
+
+	movl $TDVMCALL_EXPOSE_REGS_MASK, %ecx
+
+	tdcall
+
+	/* TDVMCALL leaf return code is in R10 */
+	movq %r10, %rax
+
+	/* Copy hypercall result registers to arg struct if needed */
+	testq $TDX_HCALL_HAS_OUTPUT, %rsi
+	jz .Lout
+
+	movq %r10, TDX_HYPERCALL_r10(%rdi)
+	movq %r11, TDX_HYPERCALL_r11(%rdi)
+	movq %r12, TDX_HYPERCALL_r12(%rdi)
+	movq %r13, TDX_HYPERCALL_r13(%rdi)
+	movq %r14, TDX_HYPERCALL_r14(%rdi)
+	movq %r15, TDX_HYPERCALL_r15(%rdi)
+.Lout:
+	/* Restore callee-saved GPRs as mandated by the x86_64 ABI */
+	pop %r12
+	pop %r13
+	pop %r14
+	pop %r15
+
+	pop %rbp
+	ret
+
+/* Disable executable stack */
+.section .note.GNU-stack,"",%progbits
diff --git a/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx.c b/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx.c
new file mode 100644
index 000000000000..c2414523487a
--- /dev/null
+++ b/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx.c
@@ -0,0 +1,27 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include "tdx/tdcall.h"
+#include "tdx/tdx.h"
+
+uint64_t tdg_vp_vmcall_instruction_io(uint64_t port, uint64_t size,
+				      uint64_t write, uint64_t *data)
+{
+	uint64_t ret;
+	struct tdx_hypercall_args args = {
+		.r10 = TDX_HYPERCALL_STANDARD,
+		.r11 = TDG_VP_VMCALL_INSTRUCTION_IO,
+		.r12 = size,
+		.r13 = write,
+		.r14 = port,
+	};
+
+	if (write)
+		args.r15 = *data;
+
+	ret = __tdx_hypercall(&args, write ? 0 : TDX_HCALL_HAS_OUTPUT);
+
+	if (!write)
+		*data = args.r11;
+
+	return ret;
+}
diff --git a/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx_util.c b/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx_util.c
index 063ff486fb86..b302060049d5 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx_util.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx_util.c
@@ -224,6 +224,7 @@  static void tdx_enable_capabilities(struct kvm_vm *vm)
 		      KVM_X2APIC_API_USE_32BIT_IDS |
 			      KVM_X2APIC_API_DISABLE_BROADCAST_QUIRK);
 	vm_enable_cap(vm, KVM_CAP_SPLIT_IRQCHIP, 24);
+	vm_enable_cap(vm, KVM_CAP_MAX_VCPUS, 512);
 }
 
 static void tdx_configure_memory_encryption(struct kvm_vm *vm)
diff --git a/tools/testing/selftests/kvm/lib/x86_64/tdx/test_util.c b/tools/testing/selftests/kvm/lib/x86_64/tdx/test_util.c
new file mode 100644
index 000000000000..6905d0ca3877
--- /dev/null
+++ b/tools/testing/selftests/kvm/lib/x86_64/tdx/test_util.c
@@ -0,0 +1,34 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include "kvm_util_base.h"
+#include "tdx/tdx.h"
+#include "tdx/test_util.h"
+
+void run_in_new_process(void (*func)(void))
+{
+	if (fork() == 0) {
+		func();
+		exit(0);
+	}
+	wait(NULL);
+}
+
+bool is_tdx_enabled(void)
+{
+	return !!(kvm_check_cap(KVM_CAP_VM_TYPES) & BIT(KVM_X86_TDX_VM));
+}
+
+void tdx_test_success(void)
+{
+	uint64_t code = 0;
+
+	tdg_vp_vmcall_instruction_io(TDX_TEST_SUCCESS_PORT,
+				     TDX_TEST_SUCCESS_SIZE,
+				     TDG_VP_VMCALL_INSTRUCTION_IO_WRITE, &code);
+}
diff --git a/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c b/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c
new file mode 100644
index 000000000000..a18d1c9d6026
--- /dev/null
+++ b/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c
@@ -0,0 +1,45 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <signal.h>
+#include "kvm_util_base.h"
+#include "tdx/tdx_util.h"
+#include "tdx/test_util.h"
+#include "test_util.h"
+
+void guest_code_lifecycle(void)
+{
+	tdx_test_success();
+}
+
+void verify_td_lifecycle(void)
+{
+	struct kvm_vm *vm;
+	struct kvm_vcpu *vcpu;
+
+	vm = td_create();
+	td_initialize(vm, VM_MEM_SRC_ANONYMOUS, 0);
+	vcpu = td_vcpu_add(vm, 0, guest_code_lifecycle);
+	td_finalize(vm);
+
+	printf("Verifying TD lifecycle:\n");
+
+	vcpu_run(vcpu);
+	TDX_TEST_ASSERT_SUCCESS(vcpu);
+
+	kvm_vm_free(vm);
+	printf("\t ... PASSED\n");
+}
+
+int main(int argc, char **argv)
+{
+	setbuf(stdout, NULL);
+
+	if (!is_tdx_enabled()) {
+		print_skip("TDX is not supported by the KVM");
+		exit(KSFT_SKIP);
+	}
+
+	run_in_new_process(&verify_td_lifecycle);
+
+	return 0;
+}