This patch series enables the nested virtualization enlightenments for SVM. This is very similar to the enlightenments for VMX except for the fact that there is no enlightened VMCS. For SVM, VMCB is already an in-memory data structure. The supported enlightenments are: Enlightened TLB Flush: If this is enabled, ASID invalidations invalidate only gva -> hpa entries. To flush entries derived from NPT, hyper-v provided hypercalls (HvFlushGuestPhysicalAddressSpace or HvFlushGuestPhysicalAddressList) should be used. Enlightened MSR bitmap(TLFS 16.5.3): "When enabled, L0 hypervisor does not monitor the MSR bitmaps for changes. Instead, the L1 hypervisor must invalidate the corresponding clean field after making changes to one of the MSR bitmaps." Direct Virtual Flush(TLFS 16.8): The hypervisor exposes hypercalls (HvFlushVirtualAddressSpace, HvFlushVirtualAddressSpaceEx, HvFlushVirtualAddressList, and HvFlushVirtualAddressListEx) that allow operating systems to more efficiently manage the virtual TLB. The L1 hypervisor can choose to allow its guest to use those hypercalls and delegate the responsibility to handle them to the L0 hypervisor. This requires the use of a partition assist page." L2 Windows boot time was measured with and without the patch. Time was measured from power on to the login screen and was averaged over a consecutive 5 trials: Without the patch: 42 seconds With the patch: 29 seconds -- Vineeth Pillai (7): hyperv: Detect Nested virtualization support for SVM hyperv: SVM enlightened TLB flush support flag KVM: x86: hyper-v: Move the remote TLB flush logic out of vmx KVM: SVM: hyper-v: Nested enlightenments in VMCB KVM: SVM: hyper-v: Remote TLB flush for SVM KVM: SVM: hyper-v: Enlightened MSR-Bitmap support KVM: SVM: hyper-v: Direct Virtual Flush support arch/x86/include/asm/hyperv-tlfs.h | 9 +++ arch/x86/include/asm/kvm_host.h | 15 ++++ arch/x86/include/asm/svm.h | 24 ++++++- arch/x86/kernel/cpu/mshyperv.c | 10 ++- arch/x86/kvm/hyperv.c | 89 +++++++++++++++++++++++ arch/x86/kvm/hyperv.h | 12 ++++ arch/x86/kvm/svm/svm.c | 110 +++++++++++++++++++++++++++++ arch/x86/kvm/svm/svm.h | 30 +++++++- arch/x86/kvm/vmx/vmx.c | 97 ++----------------------- arch/x86/kvm/vmx/vmx.h | 10 --- 10 files changed, 302 insertions(+), 104 deletions(-) -- 2.25.1
