On 7/23/2026 7:13 AM, Lisa Wang wrote: > From: Sagi Shahar <[email protected]> > > Allocate memory for TDX boot parameters and define the utility functions > necessary to fill this memory with the boot parameters.
The code change looks good to me. But I think it's better to describe how the parameters are initialized based on the HVA when VM_MEM_SRC_SHMEM is used alongside KVM_MEM_GUEST_MEMFD. Same for the patch 10. > > Co-developed-by: Ackerley Tng <[email protected]> > Signed-off-by: Ackerley Tng <[email protected]> > Signed-off-by: Sagi Shahar <[email protected]> > Signed-off-by: Lisa Wang <[email protected]> > --- > .../selftests/kvm/include/x86/tdx/tdx_util.h | 2 + > tools/testing/selftests/kvm/lib/x86/processor.c | 2 + > tools/testing/selftests/kvm/lib/x86/tdx/tdx_util.c | 51 > ++++++++++++++++++++++ > 3 files changed, 55 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 642ffa010da3..f5003cbaa106 100644 > --- a/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h > +++ b/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h > @@ -46,5 +46,7 @@ static inline bool is_tdx_vm(struct kvm_vm *vm) > > void tdx_init_vm(struct kvm_vm *vm, u64 attributes); > void tdx_vm_setup_boot_code_region(struct kvm_vm *vm); > +void tdx_vm_setup_boot_parameters_region(struct kvm_vm *vm, u32 > nr_runnable_vcpus); > +void tdx_vm_load_common_boot_parameters(struct kvm_vm *vm); > > #endif /* SELFTESTS_TDX_TDX_UTIL_H */ > diff --git a/tools/testing/selftests/kvm/lib/x86/processor.c > b/tools/testing/selftests/kvm/lib/x86/processor.c > index f93953777ca1..748c6041f8bf 100644 > --- a/tools/testing/selftests/kvm/lib/x86/processor.c > +++ b/tools/testing/selftests/kvm/lib/x86/processor.c > @@ -794,6 +794,8 @@ void kvm_arch_vm_post_create(struct kvm_vm *vm, unsigned > int nr_vcpus) > if (is_tdx_vm(vm)) { > tdx_init_vm(vm, 0); > tdx_vm_setup_boot_code_region(vm); > + tdx_vm_setup_boot_parameters_region(vm, nr_vcpus); > + tdx_vm_load_common_boot_parameters(vm); > } > > r = __vm_ioctl(vm, KVM_GET_TSC_KHZ, NULL); > 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 d64d153d19e2..2ce8c297f7ed 100644 > --- a/tools/testing/selftests/kvm/lib/x86/tdx/tdx_util.c > +++ b/tools/testing/selftests/kvm/lib/x86/tdx/tdx_util.c > @@ -6,6 +6,7 @@ > > /* 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 > @@ -49,6 +50,56 @@ void tdx_vm_setup_boot_code_region(struct kvm_vm *vm) > hva[2] = 0xcc; > } > > +void tdx_vm_setup_boot_parameters_region(struct kvm_vm *vm, u32 > 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); > + const u64 gmem_flags = 0; > + gpa_t gpa; > + > + vm_mem_add(vm, VM_MEM_SRC_SHMEM, TD_BOOT_PARAMETERS_GPA, > + TD_BOOT_PARAMETERS_SLOT, npages, > + KVM_MEM_GUEST_MEMFD, -1, 0, gmem_flags); > + 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 tdx_vm_load_common_boot_parameters(struct kvm_vm *vm) > +{ > + struct td_boot_parameters *params = > + addr_gpa2hva(vm, TD_BOOT_PARAMETERS_GPA); > + u32 cr4; > + > + cr4 = kvm_get_default_cr4(vm->mmu.pgtable_levels); > + > + /* TDX spec 11.6.2: CR4 bit MCE is fixed to 1 */ > + cr4 |= X86_CR4_MCE; > + > + /* 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(); > + TEST_ASSERT(vm->mmu.pgd < (1ULL << 32), > + "PGD must be within 32-bit address space for 32-bit boot > code"); > + params->cr3 = vm->mmu.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"); > +} > + > static struct kvm_tdx_capabilities *tdx_read_capabilities(struct kvm_vm *vm) > { > static struct kvm_tdx_capabilities *tdx_cap; >
