On Wed, Jan 05, 2022, Michael Roth wrote:
On Wed, Jan 05, 2022 at 07:40:57PM +0000, Sean Christopherson wrote:
As for ucall_init(), I think the best approach would be to make kvm_vm_elf_load() a static and replace all calls with:
kvm_vm_load_guest(vm);
where its implementation is:
void kvm_vm_load_guest(struct kvm_vm *vm) { kvm_vm_elf_load(vm, program_invocation_name);
ucall_init(vm); }
The logic being that if a test creates a VM but never loads any code into the guest, e.g. kvm_create_max_vcpus, then it _can't_ make ucalls.
Makes sense. And if different ops are needed for vmgexit()/tdcall() it could be something like (if based on patches 1-5 of this series, and extending vm_guest_mode as you suggested earlier):
void kvm_vm_load_guest(struct kvm_vm *vm) {
kvm_vm_elf_load(vm, program_invocation_name);if (vm->mode == VM_MODE_SEV) ucall_init_ops(vm, ucall_ops_pio_vmgexit); else (vm->vm_type == VM_MODE_TDX)
I don't think we want to do this here, but instead down in the arch-specific ucall_init(). Also, not sure if I was clear before (can't tell what you interpreted based on the above snippet), but I think we'll want VM_MODE_SEV etc... to be modifiers on top of the VA/PA stuff.
ucall_init_ops(vm, ucall_ops_pio_tdcall); else ucall_init_ops(vm, ucall_ops_pio);Shame we have to update all the kvm_vm_elf_load() call-sites, but they'd end up potentially breaking things if left as-is anyway.
Were you planning on sending patches for these changes, or should I incorporate your prototype and take a stab at the other changes as part of v2 of this series?
Nope, all yours. Thanks!