Messages in this thread | | | Subject | Re: [PATCH v5 0/7] Hyper-V nested virt enlightenments for SVM | From | Paolo Bonzini <> | Date | Thu, 10 Jun 2021 17:17:02 +0200 |
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On 03/06/21 17:14, Vineeth Pillai wrote: > 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 > architectural in-memory data structure. > > Note: v5 is just a rebase on hyperv-next(5.13-rc1) and needed a rework > based on the patch series: (KVM: VMX: Clean up Hyper-V PV TLB flush) > https://lore.kernel.org/lkml/20210305183123.3978098-1-seanjc@google.com/ > > 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 > -- > > Changes from v4 > - Rebased on top of 5.13-rc1 and reworked based on the changes in the > patch series: (KVM: VMX: Clean up Hyper-V PV TLB flush) > > Changes from v3 > - Included definitions for software/hypervisor reserved fields in SVM > architectural data structures. > - Consolidated Hyper-V specific code into svm_onhyperv.[ch] to reduce > the "ifdefs". This change applies only to SVM, VMX is not touched and > is not in the scope of this patch series. > > Changes from v2: > - Refactored the Remote TLB Flush logic into separate hyperv specific > source files (kvm_onhyperv.[ch]). > - Reverted the VMCB Clean bits macro changes as it is no longer needed. > > Changes from v1: > - Move the remote TLB flush related fields from kvm_vcpu_hv and kvm_hv > to kvm_vcpu_arch and kvm_arch. > - Modify the VMCB clean mask runtime based on whether L1 hypervisor > is running on Hyper-V or not. > - Detect Hyper-V nested enlightenments based on > HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS. > - Address other minor review comments. > --- > > 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: Software reserved fields > 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 | 9 ++ > arch/x86/include/asm/svm.h | 9 +- > arch/x86/include/uapi/asm/svm.h | 3 + > arch/x86/kernel/cpu/mshyperv.c | 10 ++- > arch/x86/kvm/Makefile | 9 ++ > arch/x86/kvm/kvm_onhyperv.c | 93 +++++++++++++++++++++ > arch/x86/kvm/kvm_onhyperv.h | 32 +++++++ > arch/x86/kvm/svm/svm.c | 14 ++++ > arch/x86/kvm/svm/svm.h | 22 ++++- > arch/x86/kvm/svm/svm_onhyperv.c | 41 +++++++++ > arch/x86/kvm/svm/svm_onhyperv.h | 129 +++++++++++++++++++++++++++++ > arch/x86/kvm/vmx/vmx.c | 105 +---------------------- > arch/x86/kvm/vmx/vmx.h | 9 -- > arch/x86/kvm/x86.c | 9 ++ > 15 files changed, 384 insertions(+), 119 deletions(-) > create mode 100644 arch/x86/kvm/kvm_onhyperv.c > create mode 100644 arch/x86/kvm/kvm_onhyperv.h > create mode 100644 arch/x86/kvm/svm/svm_onhyperv.c > create mode 100644 arch/x86/kvm/svm/svm_onhyperv.h >
Queued, thanks.
Paolo
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