[PATCH v2 0/7] x86/kvm/hyper-v: Implement KVM_GET_SUPPORTED_HV_CPUID

Vitaly Kuznetsov
2018-12-10T17:21:52Z

Changes since v1:
- Add Michael's R-b tags.
- Document KVM_GET_SUPPORTED_HV_CPUID and KVM_CAP_HYPERV_CPUID.
- Fix error handling in kvm_vcpu_ioctl_get_hv_cpuid().
- Check for -E2BIG in the selftest. PATCH6 is added to support the change.

As suggested by Paolo, introduce new KVM_GET_SUPPORTED_HV_CPUID returning
all Hyper-V CPUID feature leaves, this way we won't need to add a new
KVM_CAP_HYPERV_* for every new Hyper-V enlightenment we implement in
KVM.

(Using the existing KVM_GET_SUPPORTED_CPUID doesn't seem to be possible:
Hyper-V CPUID feature leaves intersect with KVM's (e.g. 0x40000000,
0x40000001) and we would probably confuse userspace in case we decide to
return these twice).

This patch series also does some housekeeping work in hyperv-tlfs.h, adds a
simple selftest (that's how I actually checked that the newly added ioctl
works) and removes recently added KVM_CAP_HYPERV_STIMER_DIRECT before it's
too late.

Vitaly Kuznetsov (7):
x86/hyper-v: Do some housekeeping in hyperv-tlfs.h
x86/hyper-v: Drop HV_X64_CONFIGURE_PROFILER definition
x86/kvm/hyper-v: Introduce nested_get_evmcs_version() helper
x86/kvm/hyper-v: Introduce KVM_GET_SUPPORTED_HV_CPUID
x86/kvm/hyper-v: Drop KVM_CAP_HYPERV_STIMER_DIRECT
KVM: selftests: implement an unchecked version of vcpu_ioctl()
KVM: selftests: Add hyperv_cpuid test

Documentation/virtual/kvm/api.txt | 57 ++++++
arch/x86/include/asm/hyperv-tlfs.h | 185 +++++++++---------
arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/kvm/hyperv.c | 125 +++++++++++-
arch/x86/kvm/hyperv.h | 2 +
arch/x86/kvm/svm.c | 7 +
arch/x86/kvm/vmx.c | 24 ++-
arch/x86/kvm/x86.c | 21 +-
include/uapi/linux/kvm.h | 5 +-
tools/testing/selftests/kvm/Makefile | 1 +
.../testing/selftests/kvm/include/kvm_util.h | 2 +
tools/testing/selftests/kvm/lib/kvm_util.c | 14 +-
.../selftests/kvm/x86_64/hyperv_cpuid.c | 157 +++++++++++++++
13 files changed, 493 insertions(+), 108 deletions(-)
create mode 100644 tools/testing/selftests/kvm/x86_64/hyperv_cpuid.c

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2.19.2