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KVM: nVMX: do not start the preemption timer hrtimer unnecessarily

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The preemption timer can be started even if there is a vmentry
failure during or after loading guest state.  That is pointless,
move the call after all conditions have been checked.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini 2019-01-29 19:14:46 +01:00
parent d92935979a
commit 359a6c3ddc
1 changed files with 9 additions and 4 deletions
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13
arch/x86/kvm/vmx/nested.c
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@ -2278,10 +2278,6 @@ static int prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12,
}
vmx_set_rflags(vcpu, vmcs12->guest_rflags);
vmx->nested.preemption_timer_expired = false;
if (nested_cpu_has_preemption_timer(vmcs12))
vmx_start_preemption_timer(vcpu);
/* EXCEPTION_BITMAP and CR0_GUEST_HOST_MASK should basically be the
* bitwise-or of what L1 wants to trap for L2, and what we want to
* trap. Note that CR0.TS also needs updating - we do this later.
@ -3018,6 +3014,15 @@ int nested_vmx_enter_non_root_mode(struct kvm_vcpu *vcpu, bool from_vmentry)
if (unlikely(evaluate_pending_interrupts))
kvm_make_request(KVM_REQ_EVENT, vcpu);
/*
* Do not start the preemption timer hrtimer until after we know
* we are successful, so that only nested_vmx_vmexit needs to cancel
* the timer.
*/
vmx->nested.preemption_timer_expired = false;
if (nested_cpu_has_preemption_timer(vmcs12))
vmx_start_preemption_timer(vcpu);
/*
* Note no nested_vmx_succeed or nested_vmx_fail here. At this point
* we are no longer running L1, and VMLAUNCH/VMRESUME has not yet