On Tue, Aug 26, 2025 at 3:36 AM Binbin Wu <binbin...@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 <ackerley...@google.com>
> > Signed-off-by: Ackerley Tng <ackerley...@google.com>
> > Signed-off-by: Sagi Shahar <sa...@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;
> > +}
>
