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    Subject[PATCH v7 0/4] Introduce Notify VM exit
    Date
    Virtual machines can exploit Intel ISA characterstics to cause
    functional denial of service to the VMM. This series introduces a new
    feature named Notify VM exit, which can help mitigate such kind of
    attacks.

    Patch 1: An extension of KVM_SET_VCPU_EVENTS ioctl to inject a
    synthesized shutdown event from user space. This is also a fix for other
    synthesized triple fault, e.g. the RSM patch or nested_vmx_abort(),
    which could get lost when exit to userspace to do migrate.

    Patch 2: A selftest about get/set triple fault event.

    Patch 3: Introduce struct kvm_caps to track misc global KVM cap/setting.

    Patch 4: The main patch to enable Notify VM exit.

    ---
    Change logs:
    v6 -> v7
    - Introduce a new cap KVM_CAP_TRIPLE_FAULT_EVENT to guard the extension
    of get/set triple fault event. (Sean)
    - Add patch 3 from Sean to integrate misc kvm cap/settings. (Sean)
    - Add the kvm lock around the notify_window and flag setting. (Sean)
    - v6: https://lore.kernel.org/lkml/20220421072958.16375-1-chenyi.qiang@intel.com/

    v5 -> v6
    - Do some changes in document.
    - Add a selftest about get/set triple fault event. (Sean)
    - extend the argument to include both the notify window and some flags
    when enabling KVM_CAP_X86_BUS_LOCK_EXIT CAP. (Sean)
    - Change to use KVM_VCPUEVENT_VALID_TRIPE_FAULT in flags field and add
    pending_triple_fault field in struct kvm_vcpu_events, which allows
    userspace to make/clear triple fault request. (Sean)
    - Add a flag in kvm_x86_ops to avoid the kvm_has_notify_vmexit global
    varialbe and its export.(Sean)
    - v5: https://lore.kernel.org/lkml/20220318074955.22428-1-chenyi.qiang@intel.com/

    v4 -> v5
    - rename KVM_VCPUEVENTS_SHUTDOWN to KVM_VCPUEVENTS_TRIPLE_FAULT. Make it
    bidirection and add it to get_vcpu_events. (Sean)
    - v4: https://lore.kernel.org/all/20220310084001.10235-1-chenyi.qiang@intel.com/

    v3 -> v4
    - Change this feature to per-VM scope. (Jim)
    - Once VM_CONTEXT_INVALID set in exit_qualification, exit to user space
    notify this fatal case, especially the notify VM exit happens in L2.
    (Jim)
    - extend KVM_SET_VCPU_EVENTS to allow user space to inject a shutdown
    event. (Jim)
    - A minor code changes.
    - Add document for the new KVM capability.
    - v3: https://lore.kernel.org/lkml/20220223062412.22334-1-chenyi.qiang@intel.com/

    v2 -> v3
    - add a vcpu state notify_window_exits to record the number of
    occurence as well as a pr_warn output. (Sean)
    - Add the handling in nested VM to prevent L1 bypassing the restriction
    through launching a L2. (Sean)
    - Only kill L2 when L2 VM is context invalid, synthesize a
    EXIT_REASON_TRIPLE_FAULT to L1 (Sean)
    - To ease the current implementation, make module parameter
    notify_window read-only. (Sean)
    - Disable notify window exit by default.
    - v2: https://lore.kernel.org/lkml/20210525051204.1480610-1-tao3.xu@intel.com/

    v1 -> v2
    - Default set notify window to 0, less than 0 to disable.
    - Add more description in commit message.
    ---

    Chenyi Qiang (2):
    KVM: x86: Extend KVM_{G,S}ET_VCPU_EVENTS to support pending triple
    fault
    KVM: selftests: Add a test to get/set triple fault event

    Sean Christopherson (1):
    KVM: x86: Introduce "struct kvm_caps" to track misc caps/settings

    Tao Xu (1):
    KVM: VMX: Enable Notify VM exit

    Documentation/virt/kvm/api.rst | 57 +++++++
    arch/x86/include/asm/kvm_host.h | 24 ++-
    arch/x86/include/asm/vmx.h | 7 +
    arch/x86/include/asm/vmxfeatures.h | 1 +
    arch/x86/include/uapi/asm/kvm.h | 6 +-
    arch/x86/include/uapi/asm/vmx.h | 4 +-
    arch/x86/kvm/cpuid.c | 8 +-
    arch/x86/kvm/debugfs.c | 4 +-
    arch/x86/kvm/lapic.c | 2 +-
    arch/x86/kvm/svm/nested.c | 4 +-
    arch/x86/kvm/svm/svm.c | 13 +-
    arch/x86/kvm/vmx/capabilities.h | 6 +
    arch/x86/kvm/vmx/nested.c | 12 +-
    arch/x86/kvm/vmx/vmx.c | 62 ++++++--
    arch/x86/kvm/x86.c | 140 +++++++++++-------
    arch/x86/kvm/x86.h | 33 ++++-
    include/uapi/linux/kvm.h | 11 ++
    tools/testing/selftests/kvm/.gitignore | 1 +
    tools/testing/selftests/kvm/Makefile | 1 +
    .../kvm/x86_64/triple_fault_event_test.c | 101 +++++++++++++
    20 files changed, 390 insertions(+), 107 deletions(-)
    create mode 100644 tools/testing/selftests/kvm/x86_64/triple_fault_event_test.c

    --
    2.17.1

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