[v5,0/4] KVM: nSVM: ondemand nested state allocation

Message

Maxim Levitsky Sept. 21, 2020, 1:19 p.m. UTC

This is yet another version of ondemand nested state allocation.

In this version I adoped the suggestion of Sean Christopherson
to return make EFER write return a negative error which then should
propogate to the userspace.

So I fixed the WRMSR code to actually obey this (#GP on positive
return value, exit to userspace when negative error value,
and success on 0 error value, and fixed one user (xen)
that returned negative error code on failures.

The XEN patch is only compile tested. The rest were tested
by always returning -ENOMEM from svm_allocate_nested.

Best regards,
	Maxim Levitsky

Maxim Levitsky (4):
  KVM: x86: xen_hvm_config cleanup return values
  KVM: x86: report negative values from wrmsr to userspace
  KVM: x86: allow kvm_x86_ops.set_efer to return a value
  KVM: nSVM: implement ondemand allocation of the nested state

 arch/x86/include/asm/kvm_host.h |  2 +-
 arch/x86/kvm/emulate.c          |  7 ++--
 arch/x86/kvm/svm/nested.c       | 42 ++++++++++++++++++++++++
 arch/x86/kvm/svm/svm.c          | 58 +++++++++++++++++++--------------
 arch/x86/kvm/svm/svm.h          |  8 ++++-
 arch/x86/kvm/vmx/vmx.c          |  9 +++--
 arch/x86/kvm/x86.c              | 36 ++++++++++----------
 7 files changed, 113 insertions(+), 49 deletions(-)