On Thu, Jul 11, 2024 at 7:37 AM Binbin Wu <binbin.wu@xxxxxxxxxxxxxxx> wrote: > On 7/11/2024 1:40 AM, Paolo Bonzini wrote: > > Wire KVM_PRE_FAULT_MEMORY ioctl to __kvm_mmu_do_page_fault() to populate guest > > __kvm_mmu_do_page_fault() -> kvm_mmu_do_page_fault() > > > memory. It can be called right after KVM_CREATE_VCPU creates a vCPU, > > since at that point kvm_mmu_create() and kvm_init_mmu() are called and > > the vCPU is ready to invoke the KVM page fault handler. > > > > The helper function kvm_mmu_map_tdp_page take care of the logic to > > kvm_mmu_map_tdp_page -> kvm_tdp_map_page()? Yes, will fix. > > diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig > > index 80e5afde69f4..4287a8071a3a 100644 > > --- a/arch/x86/kvm/Kconfig > > +++ b/arch/x86/kvm/Kconfig > > @@ -44,6 +44,7 @@ config KVM > > select KVM_VFIO > > select HAVE_KVM_PM_NOTIFIER if PM > > select KVM_GENERIC_HARDWARE_ENABLING > > + select KVM_GENERIC_PRE_FAULT_MEMORY > > select KVM_WERROR if WERROR > > help > > Support hosting fully virtualized guest machines using hardware > [...] > > index ba0ad76f53bc..a6968eadd418 100644 > > --- a/arch/x86/kvm/x86.c > > +++ b/arch/x86/kvm/x86.c > > @@ -4705,6 +4705,9 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) > > case KVM_CAP_MEMORY_FAULT_INFO: > > r = 1; > > break; > > + case KVM_CAP_PRE_FAULT_MEMORY: > > + r = tdp_enabled; > > + break; > If !CONFIG_KVM_GENERIC_PRE_FAULT_MEMORY, this should return 0. This is x86-specific code and it CONFIG_KVM_GENERIC_PRE_FAULT_MEMORY is always selected by CONFIG_KVM on x86 (that is, it does not depend on TDX or anything else). Paolo
