Commit ffdf7f9e authored by Paolo Bonzini's avatar Paolo Bonzini
Browse files

KVM: nSVM: extract svm_set_gif 



Extract the code that is needed to implement CLGI and STGI,
so that we can run it from VMRUN and vmexit (and in the future,
KVM_SET_NESTED_STATE).  Skip the request for KVM_REQ_EVENT unless needed,
subsuming the evaluate_pending_interrupts optimization that is found
in enter_svm_guest_mode.

Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 31031098

arch/x86/kvm/irq.c

+1 −0
Original line number Diff line number Diff line
@@ -83,6 +83,7 @@ int kvm_cpu_has_injectable_intr(struct kvm_vcpu *v) 


	return kvm_apic_has_interrupt(v) != -1; /* LAPIC */

}

EXPORT_SYMBOL_GPL(kvm_cpu_has_injectable_intr);



/*

 * check if there is pending interrupt without

arch/x86/kvm/svm/nested.c

+2 −20
Original line number Diff line number Diff line
@@ -333,10 +333,6 @@ static void nested_prepare_vmcb_control(struct vcpu_svm *svm) 
void enter_svm_guest_mode(struct vcpu_svm *svm, u64 vmcb_gpa,

			  struct vmcb *nested_vmcb)

{

	bool evaluate_pending_interrupts =

		is_intercept(svm, INTERCEPT_VINTR) ||

		is_intercept(svm, INTERCEPT_IRET);



	svm->nested.vmcb = vmcb_gpa;

	if (kvm_get_rflags(&svm->vcpu) & X86_EFLAGS_IF)

		svm->vcpu.arch.hflags |= HF_HIF_MASK;
@@ -347,21 +343,7 @@ void enter_svm_guest_mode(struct vcpu_svm *svm, u64 vmcb_gpa, 
	nested_prepare_vmcb_save(svm, nested_vmcb);

	nested_prepare_vmcb_control(svm);



	/*

	 * If L1 had a pending IRQ/NMI before executing VMRUN,

	 * which wasn't delivered because it was disallowed (e.g.

	 * interrupts disabled), L0 needs to evaluate if this pending

	 * event should cause an exit from L2 to L1 or be delivered

	 * directly to L2.

	 *

	 * Usually this would be handled by the processor noticing an

	 * IRQ/NMI window request.  However, VMRUN can unblock interrupts

	 * by implicitly setting GIF, so force L0 to perform pending event

	 * evaluation by requesting a KVM_REQ_EVENT.

	 */

	enable_gif(svm);

	if (unlikely(evaluate_pending_interrupts))

		kvm_make_request(KVM_REQ_EVENT, &svm->vcpu);

	svm_set_gif(svm, true);

}



int nested_svm_vmrun(struct vcpu_svm *svm)
@@ -505,7 +487,7 @@ int nested_svm_vmexit(struct vcpu_svm *svm) 
	svm->vcpu.arch.mp_state = KVM_MP_STATE_RUNNABLE;



	/* Give the current vmcb to the guest */

	disable_gif(svm);

	svm_set_gif(svm, false);



	nested_vmcb->save.es     = vmcb->save.es;

	nested_vmcb->save.cs     = vmcb->save.cs;

arch/x86/kvm/svm/svm.c

+34 −17
Original line number Diff line number Diff line
@@ -1981,29 +1981,39 @@ static int vmrun_interception(struct vcpu_svm *svm) 
	return nested_svm_vmrun(svm);

}



static int stgi_interception(struct vcpu_svm *svm)

void svm_set_gif(struct vcpu_svm *svm, bool value)

{

	int ret;



	if (nested_svm_check_permissions(svm))

		return 1;



	if (value) {

		/*

		 * If VGIF is enabled, the STGI intercept is only added to

		 * detect the opening of the SMI/NMI window; remove it now.

		 * Likewise, clear the VINTR intercept, we will set it

		 * again while processing KVM_REQ_EVENT if needed.

		 */

		if (vgif_enabled(svm))

			clr_intercept(svm, INTERCEPT_STGI);



	ret = kvm_skip_emulated_instruction(&svm->vcpu);

	kvm_make_request(KVM_REQ_EVENT, &svm->vcpu);

		if (is_intercept(svm, SVM_EXIT_VINTR))

			svm_clear_vintr(svm);



		enable_gif(svm);

		if (svm->vcpu.arch.smi_pending ||

		    svm->vcpu.arch.nmi_pending ||

		    kvm_cpu_has_injectable_intr(&svm->vcpu))

			kvm_make_request(KVM_REQ_EVENT, &svm->vcpu);

	} else {

		disable_gif(svm);



	return ret;

		/*

		 * After a CLGI no interrupts should come.  But if vGIF is

		 * in use, we still rely on the VINTR intercept (rather than

		 * STGI) to detect an open interrupt window.

		*/

		if (!vgif_enabled(svm))

			svm_clear_vintr(svm);

	}

}



static int clgi_interception(struct vcpu_svm *svm)

static int stgi_interception(struct vcpu_svm *svm)

{

	int ret;
@@ -2011,12 +2021,19 @@ static int clgi_interception(struct vcpu_svm *svm) 
		return 1;



	ret = kvm_skip_emulated_instruction(&svm->vcpu);

	svm_set_gif(svm, true);

	return ret;

}



	disable_gif(svm);

static int clgi_interception(struct vcpu_svm *svm)

{

	int ret;



	/* After a CLGI no interrupts should come */

	svm_clear_vintr(svm);

	if (nested_svm_check_permissions(svm))

		return 1;



	ret = kvm_skip_emulated_instruction(&svm->vcpu);

	svm_set_gif(svm, false);

	return ret;

}

arch/x86/kvm/svm/svm.h

+1 −0
Original line number Diff line number Diff line
@@ -357,6 +357,7 @@ void disable_nmi_singlestep(struct vcpu_svm *svm); 
bool svm_smi_blocked(struct kvm_vcpu *vcpu);

bool svm_nmi_blocked(struct kvm_vcpu *vcpu);

bool svm_interrupt_blocked(struct kvm_vcpu *vcpu);

void svm_set_gif(struct vcpu_svm *svm, bool value);



/* nested.c */

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