Re: [PATCH 11/18] KVM: selftests: Map x86's exception_handlers at VM creation, not vCPU setup

From: Ackerley Tng
Date: Wed Mar 27 2024 - 22:35:59 EST


Sean Christopherson <seanjc@xxxxxxxxxx> writes:

> Map x86's exception handlers at VM creation, not vCPU setup, as the
> mapping is per-VM, i.e. doesn't need to be (re)done for every vCPU.
>
> Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
> ---
> tools/testing/selftests/kvm/lib/x86_64/processor.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
> index 5813d93b2e7c..f4046029f168 100644
> --- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
> +++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
> @@ -552,7 +552,6 @@ static void vcpu_init_descriptor_tables(struct kvm_vcpu *vcpu)
> sregs.gdt.limit = getpagesize() - 1;
> kvm_seg_set_kernel_data_64bit(NULL, DEFAULT_DATA_SELECTOR, &sregs.gs);
> vcpu_sregs_set(vcpu, &sregs);
> - *(vm_vaddr_t *)addr_gva2hva(vm, (vm_vaddr_t)(&exception_handlers)) = vm->handlers;
> }
>
> static void vcpu_init_sregs(struct kvm_vm *vm, struct kvm_vcpu *vcpu)
> @@ -651,6 +650,8 @@ static void vm_init_descriptor_tables(struct kvm_vm *vm)
> for (i = 0; i < NUM_INTERRUPTS; i++)
> set_idt_entry(vm, i, (unsigned long)(&idt_handlers)[i], 0,
> DEFAULT_CODE_SELECTOR);
> +
> + *(vm_vaddr_t *)addr_gva2hva(vm, (vm_vaddr_t)(&exception_handlers)) = vm->handlers;
> }
>
> void vm_install_exception_handler(struct kvm_vm *vm, int vector,
> --
> 2.44.0.291.gc1ea87d7ee-goog

Reviewed-by: Ackerley Tng <ackerleytng@xxxxxxxxxx>