[PATCH v3 0/6] kvm: x86: better handling of optional kvm_x86_ops

[Paolo Bonzini <pbonzini@redhat.com>]

This series is really two changes:

- patch 1 remove a kvm_x86_ops callback.

- patch 2 to 5 clean up optional kvm_x86_ops so that they are marked
  in kvm-x86-ops.h and the non-optional ones WARN if used incorrectly.
  As an additional outcome of the review, a few more uses of
  static_call_cond are introduced.

- patch 6 allows to NULL a few kvm_x86_ops that return a value, by
  using __static_call_ret0.

v1->v2:
- use KVM_X86_OP_OPTIONAL and KVM_X86_OP_OPTIONAL_RET0
- mark load_eoi_exitmap and set_virtual_apic_mode as optional
- fix module compilation of KVM

v2->v3:
- new patch 1 to remove .has_accelerated_tpr
- do not expand KVM_X86_OP_OPTIONAL in KVM_X86_OP
- cosmetic changes to comments

Paolo Bonzini (6):
  KVM: x86: return 1 unconditionally for availability of KVM_CAP_VAPIC
  KVM: x86: use static_call_cond for optional callbacks
  KVM: x86: remove KVM_X86_OP_NULL and mark optional kvm_x86_ops
  KVM: x86: warn on incorrectly NULL members of kvm_x86_ops
  KVM: x86: make several AVIC callbacks optional
  KVM: x86: allow defining return-0 static calls

 arch/x86/include/asm/kvm-x86-ops.h | 104 +++++++++++++++--------------
 arch/x86/include/asm/kvm_host.h    |  14 ++--
 arch/x86/kvm/lapic.c               |  24 +++----
 arch/x86/kvm/svm/avic.c            |  23 -------
 arch/x86/kvm/svm/svm.c             |  30 ---------
 arch/x86/kvm/svm/svm.h             |   1 -
 arch/x86/kvm/vmx/vmx.c             |   6 --
 arch/x86/kvm/x86.c                 |  20 ++----
 kernel/static_call.c               |   1 +
 9 files changed, 81 insertions(+), 142 deletions(-)

-- 
2.31.1