RFC: https://lore.kernel.org/kvm/20231010160300.1136799-1-vkuznets@xxxxxxxxxx/ Changes since RFC: - Enhance Kconfig message [Max, Sean] - Introduce nested_vmx_is_evmptr12_valid [Max, Sean] - Collected R-b tags [Max] - Add a common function to allocate partition assist page [Max] - Fix KVM selftest to skip gracefully when !CONFIG_KVM_HYPERV - Other minor tweaks. KVM supports emulating Microsoft Hyper-V as well as running as a nested (L1) hypervisor on top of Hyper-V whileusing Hyper-V specific PV features. Support for the later is only compiled in when CONFIG_HYPERV is set. This series makes it possible to disable the former with a newly introduced CONFIG_KVM_HYPERV option. This helps to reduce sized of KVM modules as well as the attack surface for some specific deployments when no Windows/Hyper-V guests are expected. The size gain is significant: # CONFIG_KVM_HYPERV is not set # CONFIG_HYPERV is not set -rw-r--r--. 1 user user 3612632 Oct 10 16:53 arch/x86/kvm/kvm-amd.ko -rw-r--r--. 1 user user 5343968 Oct 10 16:53 arch/x86/kvm/kvm-intel.ko CONFIG_KVM_HYPERV=y # CONFIG_HYPERV is not set -rw-r--r--. 1 user user 3925704 Oct 10 16:51 arch/x86/kvm/kvm-amd.ko -rw-r--r--. 1 user user 5819192 Oct 10 16:51 arch/x86/kvm/kvm-intel.ko # CONFIG_KVM_HYPERV is not set CONFIG_HYPERV=m -rw-r--r--. 1 user user 3928440 Oct 10 16:40 arch/x86/kvm/kvm-amd.ko -rw-r--r--. 1 user user 8156464 Oct 10 16:40 arch/x86/kvm/kvm-intel.ko CONFIG_KVM_HYPERV=y CONFIG_HYPERV=m -rw-r--r--. 1 user user 4245440 Oct 10 16:37 arch/x86/kvm/kvm-amd.ko -rw-r--r--. 1 user user 8583872 Oct 10 16:37 arch/x86/kvm/kvm-intel.ko The series should not supposed to introduce any functional change for the "CONFIG_KVM_HYPERV=y && CONFIG_HYPERV=m/y" case. Tested with KVM selftests, kvm-unit-tests and real Windows guests on VMX and SVM. Note, kvm-unit-tests have to be updated to not fail miserably when CONFIG_KVM_HYPERV is not set, I'll send a separate series. Vitaly Kuznetsov (14): KVM: x86: xen: Remove unneeded xen context from struct kvm_arch when !CONFIG_KVM_XEN KVM: x86: hyper-v: Move Hyper-V partition assist page out of Hyper-V emulation context KVM: VMX: Split off vmx_onhyperv.{ch} from hyperv.{ch} KVM: x86: hyper-v: Introduce kvm_hv_synic_auto_eoi_set() KVM: x86: hyper-v: Introduce kvm_hv_synic_has_vector() KVM: VMX: Split off hyperv_evmcs.{ch} KVM: x86: hyper-v: Introduce kvm_hv_nested_transtion_tlb_flush() helper KVM: selftests: Make all Hyper-V tests explicitly dependent on Hyper-V emulation support in KVM KVM: selftests: Fix vmxon_pa == vmcs12_pa == -1ull vmx_set_nested_state_test for !eVMCS case KVM: x86: Make Hyper-V emulation optional KVM: nVMX: hyper-v: Introduce nested_vmx_evmptr12() and nested_vmx_is_evmptr12_valid() helpers KVM: nVMX: hyper-v: Introduce nested_vmx_evmcs() accessor KVM: nVMX: hyper-v: Hide more stuff under CONFIG_KVM_HYPERV KVM: nSVM: hyper-v: Hide more stuff under CONFIG_KVM_HYPERV/CONFIG_HYPERV arch/x86/include/asm/kvm_host.h | 11 +- arch/x86/kvm/Kconfig | 14 + arch/x86/kvm/Makefile | 19 +- arch/x86/kvm/cpuid.c | 6 + arch/x86/kvm/hyperv.h | 52 +- arch/x86/kvm/irq.c | 2 + arch/x86/kvm/irq_comm.c | 9 +- arch/x86/kvm/kvm_onhyperv.h | 20 + arch/x86/kvm/lapic.c | 5 +- arch/x86/kvm/svm/hyperv.h | 7 + arch/x86/kvm/svm/nested.c | 30 +- arch/x86/kvm/svm/svm.h | 2 + arch/x86/kvm/svm/svm_onhyperv.c | 10 +- arch/x86/kvm/vmx/hyperv.c | 447 ------------------ arch/x86/kvm/vmx/hyperv.h | 196 ++------ arch/x86/kvm/vmx/hyperv_evmcs.c | 315 ++++++++++++ arch/x86/kvm/vmx/hyperv_evmcs.h | 166 +++++++ arch/x86/kvm/vmx/nested.c | 102 ++-- arch/x86/kvm/vmx/nested.h | 3 +- arch/x86/kvm/vmx/vmx.c | 18 +- arch/x86/kvm/vmx/vmx.h | 2 + arch/x86/kvm/vmx/vmx_onhyperv.c | 36 ++ arch/x86/kvm/vmx/vmx_onhyperv.h | 125 +++++ arch/x86/kvm/vmx/vmx_ops.h | 2 +- arch/x86/kvm/x86.c | 66 ++- .../selftests/kvm/x86_64/hyperv_clock.c | 2 + .../selftests/kvm/x86_64/hyperv_evmcs.c | 5 +- .../kvm/x86_64/hyperv_extended_hypercalls.c | 2 + .../selftests/kvm/x86_64/hyperv_features.c | 2 + .../testing/selftests/kvm/x86_64/hyperv_ipi.c | 2 + .../selftests/kvm/x86_64/hyperv_svm_test.c | 1 + .../selftests/kvm/x86_64/hyperv_tlb_flush.c | 2 + .../kvm/x86_64/vmx_set_nested_state_test.c | 16 +- 33 files changed, 963 insertions(+), 734 deletions(-) create mode 100644 arch/x86/kvm/vmx/hyperv_evmcs.c create mode 100644 arch/x86/kvm/vmx/hyperv_evmcs.h create mode 100644 arch/x86/kvm/vmx/vmx_onhyperv.c create mode 100644 arch/x86/kvm/vmx/vmx_onhyperv.h -- 2.41.0
