TDX guests' registers cannot be initialized directly using vcpu_regs_set(), hence the stack pointer needs to be initialized by the guest itself, running boot code beginning at the reset vector.
We store the stack address as part of struct kvm_vcpu so that it can be accessible later to be passed to the boot code for rsp initialization.
Signed-off-by: Ackerley Tng ackerleytng@google.com --- tools/testing/selftests/kvm/include/kvm_util_base.h | 1 + tools/testing/selftests/kvm/lib/x86_64/processor.c | 4 +++- 2 files changed, 4 insertions(+), 1 deletion(-)
diff --git a/tools/testing/selftests/kvm/include/kvm_util_base.h b/tools/testing/selftests/kvm/include/kvm_util_base.h index 0fa4dab3d8e52..cdc204cfeb4c2 100644 --- a/tools/testing/selftests/kvm/include/kvm_util_base.h +++ b/tools/testing/selftests/kvm/include/kvm_util_base.h @@ -54,6 +54,7 @@ struct kvm_vcpu { int fd; struct kvm_vm *vm; struct kvm_run *run; + vm_vaddr_t initial_stack_addr; #ifdef __x86_64__ struct kvm_cpuid2 *cpuid; #endif diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c index 1bb07d3c025b0..3046b555fee49 100644 --- a/tools/testing/selftests/kvm/lib/x86_64/processor.c +++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c @@ -673,10 +673,12 @@ struct kvm_vcpu *vm_arch_vcpu_add(struct kvm_vm *vm, uint32_t vcpu_id, vcpu_init_cpuid(vcpu, kvm_get_supported_cpuid()); vcpu_setup(vm, vcpu);
+ vcpu->initial_stack_addr = stack_vaddr + (DEFAULT_STACK_PGS * getpagesize()); + /* Setup guest general purpose registers */ vcpu_regs_get(vcpu, ®s); regs.rflags = regs.rflags | 0x2; - regs.rsp = stack_vaddr + (DEFAULT_STACK_PGS * getpagesize()); + regs.rsp = vcpu->initial_stack_addr; regs.rip = (unsigned long) guest_code; vcpu_regs_set(vcpu, ®s);