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()?
process RET_PF_* return values and convert them to success or errno. Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx> Message-ID: <9b866a0ae7147f96571c439e75429a03dcb659b6.1712785629.git.isaku.yamahata@xxxxxxxxx> Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx> --- arch/x86/kvm/Kconfig | 1 + arch/x86/kvm/mmu/mmu.c | 73 ++++++++++++++++++++++++++++++++++++++++++ arch/x86/kvm/x86.c | 3 ++ 3 files changed, 77 insertions(+) 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.
case KVM_CAP_EXIT_HYPERCALL: r = KVM_EXIT_HYPERCALL_VALID_MASK; break;