Allocate memory for TDX boot parameters and define the utility functions
necessary to fill this memory with the boot parameters.
Co-developed-by: Ackerley Tng <ackerleytng@google.com>
Signed-off-by: Ackerley Tng <ackerleytng@google.com>
Signed-off-by: Sagi Shahar <sagis@google.com>
---
.../selftests/kvm/include/x86/tdx/tdx_util.h | 4 +
.../selftests/kvm/lib/x86/tdx/tdx_util.c | 73 +++++++++++++++++++
2 files changed, 77 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 ec05bcd59145..dafdc7e46abe 100644
--- a/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h
+++ b/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h
@@ -12,5 +12,9 @@ static inline bool is_tdx_vm(struct kvm_vm *vm)
}
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);
+void vm_tdx_load_vcpu_boot_parameters(struct kvm_vm *vm, struct kvm_vcpu *vcpu);
+void vm_tdx_set_vcpu_entry_point(struct kvm_vcpu *vcpu, void *guest_code);
#endif // SELFTESTS_TDX_TDX_UTIL_H
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 15833b9eb5d5..52dc25e0cce4 100644
--- a/tools/testing/selftests/kvm/lib/x86/tdx/tdx_util.c
+++ b/tools/testing/selftests/kvm/lib/x86/tdx/tdx_util.c
@@ -5,10 +5,12 @@
#include "kvm_util.h"
#include "processor.h"
#include "tdx/td_boot.h"
+#include "tdx/td_boot_asm.h"
#include "tdx/tdx_util.h"
/* Arbitrarily selected to avoid overlaps with anything else */
#define TD_BOOT_CODE_SLOT 20
+#define TD_BOOT_PARAMETERS_SLOT 21
#define X86_RESET_VECTOR 0xfffffff0ul
#define X86_RESET_VECTOR_SIZE 16
@@ -52,3 +54,74 @@ void vm_tdx_setup_boot_code_region(struct kvm_vm *vm)
hva[1] = 256 - 2 - TD_BOOT_CODE_SIZE;
hva[2] = 0xcc;
}
+
+void vm_tdx_setup_boot_parameters_region(struct kvm_vm *vm, uint32_t nr_runnable_vcpus)
+{
+ size_t boot_params_size =
+ sizeof(struct td_boot_parameters) +
+ nr_runnable_vcpus * sizeof(struct td_per_vcpu_parameters);
+ int npages = DIV_ROUND_UP(boot_params_size, PAGE_SIZE);
+ vm_paddr_t gpa;
+
+ vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS,
+ TD_BOOT_PARAMETERS_GPA,
+ TD_BOOT_PARAMETERS_SLOT, npages,
+ KVM_MEM_GUEST_MEMFD);
+ gpa = vm_phy_pages_alloc(vm, npages, TD_BOOT_PARAMETERS_GPA, TD_BOOT_PARAMETERS_SLOT);
+ TEST_ASSERT(gpa == TD_BOOT_PARAMETERS_GPA, "Failed vm_phy_pages_alloc\n");
+
+ virt_map(vm, TD_BOOT_PARAMETERS_GPA, TD_BOOT_PARAMETERS_GPA, npages);
+}
+
+void vm_tdx_load_common_boot_parameters(struct kvm_vm *vm)
+{
+ struct td_boot_parameters *params =
+ addr_gpa2hva(vm, TD_BOOT_PARAMETERS_GPA);
+ uint32_t cr4;
+
+ TEST_ASSERT_EQ(vm->mode, VM_MODE_PXXV48_4K);
+
+ cr4 = kvm_get_default_cr4();
+
+ /* TDX spec 11.6.2: CR4 bit MCE is fixed to 1 */
+ cr4 |= X86_CR4_MCE;
+
+ /* Set this because UEFI also sets this up, to handle XMM exceptions */
+ cr4 |= X86_CR4_OSXMMEXCPT;
+
+ /* TDX spec 11.6.2: CR4 bit VMXE and SMXE are fixed to 0 */
+ cr4 &= ~(X86_CR4_VMXE | X86_CR4_SMXE);
+
+ /* Set parameters! */
+ params->cr0 = kvm_get_default_cr0();
+ params->cr3 = vm->pgd;
+ params->cr4 = cr4;
+ params->idtr.base = vm->arch.idt;
+ params->idtr.limit = kvm_get_default_idt_limit();
+ params->gdtr.base = vm->arch.gdt;
+ params->gdtr.limit = kvm_get_default_gdt_limit();
+
+ TEST_ASSERT(params->cr0 != 0, "cr0 should not be 0");
+ TEST_ASSERT(params->cr3 != 0, "cr3 should not be 0");
+ TEST_ASSERT(params->cr4 != 0, "cr4 should not be 0");
+ TEST_ASSERT(params->gdtr.base != 0, "gdt base address should not be 0");
+ TEST_ASSERT(params->idtr.base != 0, "idt base address should not be 0");
+}
+
+void vm_tdx_load_vcpu_boot_parameters(struct kvm_vm *vm, struct kvm_vcpu *vcpu)
+{
+ struct td_boot_parameters *params =
+ addr_gpa2hva(vm, TD_BOOT_PARAMETERS_GPA);
+ struct td_per_vcpu_parameters *vcpu_params =
+ ¶ms->per_vcpu[vcpu->id];
+
+ vcpu_params->esp_gva = kvm_allocate_vcpu_stack(vm);
+}
+
+void vm_tdx_set_vcpu_entry_point(struct kvm_vcpu *vcpu, void *guest_code)
+{
+ struct td_boot_parameters *params = addr_gpa2hva(vcpu->vm, TD_BOOT_PARAMETERS_GPA);
+ struct td_per_vcpu_parameters *vcpu_params = ¶ms->per_vcpu[vcpu->id];
+
+ vcpu_params->guest_code = (uint64_t)guest_code;
+}
--
2.51.0.rc1.193.gad69d77794-goog
On 8/21/2025 12:29 PM, Sagi Shahar wrote:
> Allocate memory for TDX boot parameters and define the utility functions
> necessary to fill this memory with the boot parameters.
>
> Co-developed-by: Ackerley Tng <ackerleytng@google.com>
> Signed-off-by: Ackerley Tng <ackerleytng@google.com>
> Signed-off-by: Sagi Shahar <sagis@google.com>
> ---
> .../selftests/kvm/include/x86/tdx/tdx_util.h | 4 +
> .../selftests/kvm/lib/x86/tdx/tdx_util.c | 73 +++++++++++++++++++
> 2 files changed, 77 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 ec05bcd59145..dafdc7e46abe 100644
> --- a/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h
> +++ b/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h
> @@ -12,5 +12,9 @@ static inline bool is_tdx_vm(struct kvm_vm *vm)
> }
>
> 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);
> +void vm_tdx_load_vcpu_boot_parameters(struct kvm_vm *vm, struct kvm_vcpu *vcpu);
> +void vm_tdx_set_vcpu_entry_point(struct kvm_vcpu *vcpu, void *guest_code);
>
> #endif // SELFTESTS_TDX_TDX_UTIL_H
> 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 15833b9eb5d5..52dc25e0cce4 100644
> --- a/tools/testing/selftests/kvm/lib/x86/tdx/tdx_util.c
> +++ b/tools/testing/selftests/kvm/lib/x86/tdx/tdx_util.c
> @@ -5,10 +5,12 @@
> #include "kvm_util.h"
> #include "processor.h"
> #include "tdx/td_boot.h"
> +#include "tdx/td_boot_asm.h"
> #include "tdx/tdx_util.h"
>
> /* Arbitrarily selected to avoid overlaps with anything else */
> #define TD_BOOT_CODE_SLOT 20
> +#define TD_BOOT_PARAMETERS_SLOT 21
>
> #define X86_RESET_VECTOR 0xfffffff0ul
> #define X86_RESET_VECTOR_SIZE 16
> @@ -52,3 +54,74 @@ void vm_tdx_setup_boot_code_region(struct kvm_vm *vm)
> hva[1] = 256 - 2 - TD_BOOT_CODE_SIZE;
> hva[2] = 0xcc;
> }
> +
> +void vm_tdx_setup_boot_parameters_region(struct kvm_vm *vm, uint32_t nr_runnable_vcpus)
> +{
> + size_t boot_params_size =
> + sizeof(struct td_boot_parameters) +
> + nr_runnable_vcpus * sizeof(struct td_per_vcpu_parameters);
> + int npages = DIV_ROUND_UP(boot_params_size, PAGE_SIZE);
> + vm_paddr_t gpa;
> +
> + vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS,
> + TD_BOOT_PARAMETERS_GPA,
> + TD_BOOT_PARAMETERS_SLOT, npages,
> + KVM_MEM_GUEST_MEMFD);
> + gpa = vm_phy_pages_alloc(vm, npages, TD_BOOT_PARAMETERS_GPA, TD_BOOT_PARAMETERS_SLOT);
> + TEST_ASSERT(gpa == TD_BOOT_PARAMETERS_GPA, "Failed vm_phy_pages_alloc\n");
> +
> + virt_map(vm, TD_BOOT_PARAMETERS_GPA, TD_BOOT_PARAMETERS_GPA, npages);
> +}
> +
> +void vm_tdx_load_common_boot_parameters(struct kvm_vm *vm)
> +{
> + struct td_boot_parameters *params =
> + addr_gpa2hva(vm, TD_BOOT_PARAMETERS_GPA);
> + uint32_t cr4;
> +
> + TEST_ASSERT_EQ(vm->mode, VM_MODE_PXXV48_4K);
> +
> + cr4 = kvm_get_default_cr4();
> +
> + /* TDX spec 11.6.2: CR4 bit MCE is fixed to 1 */
> + cr4 |= X86_CR4_MCE;
> +
> + /* Set this because UEFI also sets this up, to handle XMM exceptions */
> + cr4 |= X86_CR4_OSXMMEXCPT;
> +
> + /* TDX spec 11.6.2: CR4 bit VMXE and SMXE are fixed to 0 */
> + cr4 &= ~(X86_CR4_VMXE | X86_CR4_SMXE);
> +
> + /* Set parameters! */
> + params->cr0 = kvm_get_default_cr0();
> + params->cr3 = vm->pgd;
> + params->cr4 = cr4;
> + params->idtr.base = vm->arch.idt;
> + params->idtr.limit = kvm_get_default_idt_limit();
> + params->gdtr.base = vm->arch.gdt;
> + params->gdtr.limit = kvm_get_default_gdt_limit();
> +
> + TEST_ASSERT(params->cr0 != 0, "cr0 should not be 0");
> + TEST_ASSERT(params->cr3 != 0, "cr3 should not be 0");
> + TEST_ASSERT(params->cr4 != 0, "cr4 should not be 0");
> + TEST_ASSERT(params->gdtr.base != 0, "gdt base address should not be 0");
> + TEST_ASSERT(params->idtr.base != 0, "idt base address should not be 0");
> +}
> +
> +void vm_tdx_load_vcpu_boot_parameters(struct kvm_vm *vm, struct kvm_vcpu *vcpu)
> +{
> + struct td_boot_parameters *params =
> + addr_gpa2hva(vm, TD_BOOT_PARAMETERS_GPA);
> + struct td_per_vcpu_parameters *vcpu_params =
> + ¶ms->per_vcpu[vcpu->id];
Nit: Better to align the style on whether wrap or not due to max characters per
line
> +
> + vcpu_params->esp_gva = kvm_allocate_vcpu_stack(vm);
> +}
> +
> +void vm_tdx_set_vcpu_entry_point(struct kvm_vcpu *vcpu, void *guest_code)
> +{
> + struct td_boot_parameters *params = addr_gpa2hva(vcpu->vm, TD_BOOT_PARAMETERS_GPA);
> + struct td_per_vcpu_parameters *vcpu_params = ¶ms->per_vcpu[vcpu->id];
> +
> + vcpu_params->guest_code = (uint64_t)guest_code;
> +}
On Tue, Aug 26, 2025 at 3:36 AM Binbin Wu <binbin.wu@linux.intel.com> wrote:
>
>
>
> On 8/21/2025 12:29 PM, Sagi Shahar wrote:
> > Allocate memory for TDX boot parameters and define the utility functions
> > necessary to fill this memory with the boot parameters.
> >
> > Co-developed-by: Ackerley Tng <ackerleytng@google.com>
> > Signed-off-by: Ackerley Tng <ackerleytng@google.com>
> > Signed-off-by: Sagi Shahar <sagis@google.com>
> > ---
> > .../selftests/kvm/include/x86/tdx/tdx_util.h | 4 +
> > .../selftests/kvm/lib/x86/tdx/tdx_util.c | 73 +++++++++++++++++++
> > 2 files changed, 77 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 ec05bcd59145..dafdc7e46abe 100644
> > --- a/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h
> > +++ b/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h
> > @@ -12,5 +12,9 @@ static inline bool is_tdx_vm(struct kvm_vm *vm)
> > }
> >
> > 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);
> > +void vm_tdx_load_vcpu_boot_parameters(struct kvm_vm *vm, struct kvm_vcpu *vcpu);
> > +void vm_tdx_set_vcpu_entry_point(struct kvm_vcpu *vcpu, void *guest_code);
> >
> > #endif // SELFTESTS_TDX_TDX_UTIL_H
> > 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 15833b9eb5d5..52dc25e0cce4 100644
> > --- a/tools/testing/selftests/kvm/lib/x86/tdx/tdx_util.c
> > +++ b/tools/testing/selftests/kvm/lib/x86/tdx/tdx_util.c
> > @@ -5,10 +5,12 @@
> > #include "kvm_util.h"
> > #include "processor.h"
> > #include "tdx/td_boot.h"
> > +#include "tdx/td_boot_asm.h"
> > #include "tdx/tdx_util.h"
> >
> > /* Arbitrarily selected to avoid overlaps with anything else */
> > #define TD_BOOT_CODE_SLOT 20
> > +#define TD_BOOT_PARAMETERS_SLOT 21
> >
> > #define X86_RESET_VECTOR 0xfffffff0ul
> > #define X86_RESET_VECTOR_SIZE 16
> > @@ -52,3 +54,74 @@ void vm_tdx_setup_boot_code_region(struct kvm_vm *vm)
> > hva[1] = 256 - 2 - TD_BOOT_CODE_SIZE;
> > hva[2] = 0xcc;
> > }
> > +
> > +void vm_tdx_setup_boot_parameters_region(struct kvm_vm *vm, uint32_t nr_runnable_vcpus)
> > +{
> > + size_t boot_params_size =
> > + sizeof(struct td_boot_parameters) +
> > + nr_runnable_vcpus * sizeof(struct td_per_vcpu_parameters);
> > + int npages = DIV_ROUND_UP(boot_params_size, PAGE_SIZE);
> > + vm_paddr_t gpa;
> > +
> > + vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS,
> > + TD_BOOT_PARAMETERS_GPA,
> > + TD_BOOT_PARAMETERS_SLOT, npages,
> > + KVM_MEM_GUEST_MEMFD);
> > + gpa = vm_phy_pages_alloc(vm, npages, TD_BOOT_PARAMETERS_GPA, TD_BOOT_PARAMETERS_SLOT);
> > + TEST_ASSERT(gpa == TD_BOOT_PARAMETERS_GPA, "Failed vm_phy_pages_alloc\n");
> > +
> > + virt_map(vm, TD_BOOT_PARAMETERS_GPA, TD_BOOT_PARAMETERS_GPA, npages);
> > +}
> > +
> > +void vm_tdx_load_common_boot_parameters(struct kvm_vm *vm)
> > +{
> > + struct td_boot_parameters *params =
> > + addr_gpa2hva(vm, TD_BOOT_PARAMETERS_GPA);
> > + uint32_t cr4;
> > +
> > + TEST_ASSERT_EQ(vm->mode, VM_MODE_PXXV48_4K);
> > +
> > + cr4 = kvm_get_default_cr4();
> > +
> > + /* TDX spec 11.6.2: CR4 bit MCE is fixed to 1 */
> > + cr4 |= X86_CR4_MCE;
> > +
> > + /* Set this because UEFI also sets this up, to handle XMM exceptions */
> > + cr4 |= X86_CR4_OSXMMEXCPT;
> > +
> > + /* TDX spec 11.6.2: CR4 bit VMXE and SMXE are fixed to 0 */
> > + cr4 &= ~(X86_CR4_VMXE | X86_CR4_SMXE);
> > +
> > + /* Set parameters! */
> > + params->cr0 = kvm_get_default_cr0();
> > + params->cr3 = vm->pgd;
> > + params->cr4 = cr4;
> > + params->idtr.base = vm->arch.idt;
> > + params->idtr.limit = kvm_get_default_idt_limit();
> > + params->gdtr.base = vm->arch.gdt;
> > + params->gdtr.limit = kvm_get_default_gdt_limit();
> > +
> > + TEST_ASSERT(params->cr0 != 0, "cr0 should not be 0");
> > + TEST_ASSERT(params->cr3 != 0, "cr3 should not be 0");
> > + TEST_ASSERT(params->cr4 != 0, "cr4 should not be 0");
> > + TEST_ASSERT(params->gdtr.base != 0, "gdt base address should not be 0");
> > + TEST_ASSERT(params->idtr.base != 0, "idt base address should not be 0");
> > +}
> > +
> > +void vm_tdx_load_vcpu_boot_parameters(struct kvm_vm *vm, struct kvm_vcpu *vcpu)
> > +{
> > + struct td_boot_parameters *params =
> > + addr_gpa2hva(vm, TD_BOOT_PARAMETERS_GPA);
> > + struct td_per_vcpu_parameters *vcpu_params =
> > + ¶ms->per_vcpu[vcpu->id];
>
> Nit: Better to align the style on whether wrap or not due to max characters per
> line
>
Thanks, going to wrap in both functions.
> > +
> > + vcpu_params->esp_gva = kvm_allocate_vcpu_stack(vm);
> > +}
> > +
> > +void vm_tdx_set_vcpu_entry_point(struct kvm_vcpu *vcpu, void *guest_code)
> > +{
> > + struct td_boot_parameters *params = addr_gpa2hva(vcpu->vm, TD_BOOT_PARAMETERS_GPA);
> > + struct td_per_vcpu_parameters *vcpu_params = ¶ms->per_vcpu[vcpu->id];
> > +
> > + vcpu_params->guest_code = (uint64_t)guest_code;
> > +}
>
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