----- chao....@intel.com wrote:
> Although L2 is in halt state, it will be in the active state after
> VM entry if the VM entry is vectoring according to SDM 26.6.2
> State. Halting the vcpu here means the event won't be injected to L2
> and this decision isn't reported to L1. Thus L0 drops an event that
> should be injected to L2.
> Cc: Liran Alon <liran.a...@oracle.com>
> Signed-off-by: Chao Gao <chao....@intel.com>
> Changes in v2:
> - Remove VID stuff. Only handle event injection in this patch.
> arch/x86/kvm/vmx.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
> index bb5b488..42f39d9 100644
> --- a/arch/x86/kvm/vmx.c
> +++ b/arch/x86/kvm/vmx.c
> @@ -10985,7 +10985,12 @@ static int nested_vmx_run(struct kvm_vcpu
> *vcpu, bool launch)
> if (ret)
> return ret;
> - if (vmcs12->guest_activity_state == GUEST_ACTIVITY_HLT)
> + /*
> + * If we're entering a halted L2 vcpu and the L2 vcpu won't be
> + * by event injection, halt vcpu for optimization.
I would remove the "for optimization." from the comment.
> + */
> + if ((vmcs12->guest_activity_state == GUEST_ACTIVITY_HLT) &&
> + !(vmcs12->vm_entry_intr_info_field &
VECTORING_INFO_VALID_MASK is used in KVM code against
I think you should use INTR_INFO_VALID_MASK to be consistent with rest of code.
> return kvm_vcpu_halt(vcpu);
> vmx->nested.nested_run_pending = 1;
In addition, commit title should be written in format of:
"KVM: VMX: Don't halt vcpu when L1 is injecting events to L2"
(Makes it easier to grep in git log).
Other than that, seems good to me. :)
Reviewed-by: Liran Alon <liran.a...@oracle.com>