[PATCH v3 00/34] KVM: x86: hyper-v: Fine-grained TLB flush + L2 TLB flush feature

Vitaly Kuznetsov
2022-04-14T13:39:28Z

Changes since v1:
To address Sean's review comments:
- s,Direct,L2, everywhere.
- s,tlbflush,tlb_flush, everywhere.
- "KVM: x86: hyper-v: Add helper to read hypercall data for array" patch
added.
- "x86/hyperv: Introduce HV_MAX_SPARSE_VCPU_BANKS/HV_VCPUS_PER_SPARSE_BANK
constants" patch added.
- "KVM: x86: hyper-v: Use HV_MAX_SPARSE_VCPU_BANKS/HV_VCPUS_PER_SPARSE_BANK
instead of raw '64'" patch added.
- Other code improvements.

Other changes:
- Rebase to the latest kvm/queue.
- "KVM: selftests: add hyperv_svm_test to .gitignore" patch dropped
(already fixed).
- "KVM: x86: Rename 'enable_direct_tlbflush' to 'enable_l2_tlb_flush'"
patch added.
- Fix a race in the newly introduced Hyper-V IPI test.

Original description:

Currently, KVM handles HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST{,EX} requests
by flushing the whole VPID and this is sub-optimal. This series introduces
the required mechanism to make handling of these requests more
fine-grained by flushing individual GVAs only (when requested). On this
foundation, "Direct Virtual Flush" Hyper-V feature is implemented. The
feature allows L0 to handle Hyper-V TLB flush hypercalls directly at
L0 without the need to reflect the exit to L1. This has at least two
benefits: reflecting vmexit and the consequent vmenter are avoided + L0
has precise information whether the target vCPU is actually running (and
thus requires a kick).

Sean Christopherson (1):
KVM: x86: hyper-v: Add helper to read hypercall data for array

Vitaly Kuznetsov (33):
KVM: x86: hyper-v: Resurrect dedicated KVM_REQ_HV_TLB_FLUSH flag
KVM: x86: hyper-v: Introduce TLB flush ring
KVM: x86: hyper-v: Handle HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST{,EX} calls
gently
KVM: x86: hyper-v: Expose support for extended gva ranges for flush
hypercalls
KVM: x86: Prepare kvm_hv_flush_tlb() to handle L2's GPAs
x86/hyperv: Introduce
HV_MAX_SPARSE_VCPU_BANKS/HV_VCPUS_PER_SPARSE_BANK constants
KVM: x86: hyper-v: Use
HV_MAX_SPARSE_VCPU_BANKS/HV_VCPUS_PER_SPARSE_BANK instead of raw
'64'
KVM: x86: hyper-v: Don't use sparse_set_to_vcpu_mask() in
kvm_hv_send_ipi()
KVM: x86: hyper-v: Create a separate ring for L2 TLB flush
KVM: x86: hyper-v: Use preallocated buffer in 'struct kvm_vcpu_hv'
instead of on-stack 'sparse_banks'
KVM: nVMX: Keep track of hv_vm_id/hv_vp_id when eVMCS is in use
KVM: nSVM: Keep track of Hyper-V hv_vm_id/hv_vp_id
KVM: x86: Introduce .post_hv_l2_tlb_flush() nested hook
KVM: x86: hyper-v: Introduce kvm_hv_is_tlb_flush_hcall()
KVM: x86: hyper-v: L2 TLB flush
KVM: x86: hyper-v: Introduce fast kvm_hv_l2_tlb_flush_exposed() check
x86/hyperv: Fix 'struct hv_enlightened_vmcs' definition
KVM: nVMX: hyper-v: Enable L2 TLB flush
KVM: x86: KVM_REQ_TLB_FLUSH_CURRENT is a superset of
KVM_REQ_HV_TLB_FLUSH too
KVM: nSVM: hyper-v: Enable L2 TLB flush
KVM: x86: Expose Hyper-V L2 TLB flush feature
KVM: selftests: Better XMM read/write helpers
KVM: selftests: Hyper-V PV IPI selftest
KVM: selftests: Make it possible to replace PTEs with __virt_pg_map()
KVM: selftests: Hyper-V PV TLB flush selftest
KVM: selftests: Sync 'struct hv_enlightened_vmcs' definition with
hyperv-tlfs.h
KVM: selftests: nVMX: Allocate Hyper-V partition assist page
KVM: selftests: nSVM: Allocate Hyper-V partition assist and VP assist
pages
KVM: selftests: Sync 'struct hv_vp_assist_page' definition with
hyperv-tlfs.h
KVM: selftests: evmcs_test: Introduce L2 TLB flush test
KVM: selftests: Move Hyper-V VP assist page enablement out of evmcs.h
KVM: selftests: hyperv_svm_test: Introduce L2 TLB flush test
KVM: x86: Rename 'enable_direct_tlbflush' to 'enable_l2_tlb_flush'

arch/x86/include/asm/hyperv-tlfs.h | 6 +-
arch/x86/include/asm/kvm-x86-ops.h | 2 +-
arch/x86/include/asm/kvm_host.h | 37 +-
arch/x86/kvm/Makefile | 3 +-
arch/x86/kvm/hyperv.c | 376 ++++++++--
arch/x86/kvm/hyperv.h | 48 ++
arch/x86/kvm/svm/hyperv.c | 18 +
arch/x86/kvm/svm/hyperv.h | 37 +
arch/x86/kvm/svm/nested.c | 25 +-
arch/x86/kvm/svm/svm_onhyperv.c | 2 +-
arch/x86/kvm/svm/svm_onhyperv.h | 6 +-
arch/x86/kvm/trace.h | 21 +-
arch/x86/kvm/vmx/evmcs.c | 24 +
arch/x86/kvm/vmx/evmcs.h | 11 +
arch/x86/kvm/vmx/nested.c | 32 +
arch/x86/kvm/vmx/vmx.c | 6 +-
arch/x86/kvm/x86.c | 20 +-
arch/x86/kvm/x86.h | 1 +
include/asm-generic/hyperv-tlfs.h | 5 +
include/asm-generic/mshyperv.h | 11 +-
tools/testing/selftests/kvm/.gitignore | 2 +
tools/testing/selftests/kvm/Makefile | 4 +-
.../selftests/kvm/include/x86_64/evmcs.h | 40 +-
.../selftests/kvm/include/x86_64/hyperv.h | 35 +
.../selftests/kvm/include/x86_64/processor.h | 72 +-
.../selftests/kvm/include/x86_64/svm_util.h | 10 +
.../selftests/kvm/include/x86_64/vmx.h | 4 +
.../testing/selftests/kvm/lib/x86_64/hyperv.c | 21 +
.../selftests/kvm/lib/x86_64/processor.c | 6 +-
tools/testing/selftests/kvm/lib/x86_64/svm.c | 10 +
tools/testing/selftests/kvm/lib/x86_64/vmx.c | 7 +
.../selftests/kvm/max_guest_memory_test.c | 2 +-
.../testing/selftests/kvm/x86_64/evmcs_test.c | 53 +-
.../selftests/kvm/x86_64/hyperv_features.c | 5 +-
.../testing/selftests/kvm/x86_64/hyperv_ipi.c | 374 ++++++++++
.../selftests/kvm/x86_64/hyperv_svm_test.c | 60 +-
.../selftests/kvm/x86_64/hyperv_tlb_flush.c | 647 ++++++++++++++++++
.../selftests/kvm/x86_64/mmu_role_test.c | 2 +-
38 files changed, 1883 insertions(+), 162 deletions(-)
create mode 100644 arch/x86/kvm/svm/hyperv.c
create mode 100644 tools/testing/selftests/kvm/lib/x86_64/hyperv.c
create mode 100644 tools/testing/selftests/kvm/x86_64/hyperv_ipi.c
create mode 100644 tools/testing/selftests/kvm/x86_64/hyperv_tlb_flush.c

--
2.35.1