Commit f2bc14b6 authored by Vitaly Kuznetsov's avatar Vitaly Kuznetsov Committed by Paolo Bonzini
Browse files

KVM: x86: hyper-v: Prepare to meet unallocated Hyper-V context 



Currently, Hyper-V context is part of 'struct kvm_vcpu_arch' and is always
available. As a preparation to allocating it dynamically, check that it is
not NULL at call sites which can normally proceed without it i.e. the
behavior is identical to the situation when Hyper-V emulation is not being
used by the guest.

When Hyper-V context for a particular vCPU is not allocated, we may still
need to get 'vp_index' from there. E.g. in a hypothetical situation when
Hyper-V emulation was enabled on one CPU and wasn't on another, Hyper-V
style send-IPI hypercall may still be used. Luckily, vp_index is always
initialized to kvm_vcpu_get_idx() and can only be changed when Hyper-V
context is present. Introduce kvm_hv_get_vpindex() helper for
simplification.

No functional change intended.

Signed-off-by: default avatarVitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210126134816.1880136-12-vkuznets@redhat.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 9ff5e030

arch/x86/kvm/hyperv.c

+10 −7
Original line number Diff line number Diff line
@@ -142,10 +142,10 @@ static struct kvm_vcpu *get_vcpu_by_vpidx(struct kvm *kvm, u32 vpidx) 
		return NULL;



	vcpu = kvm_get_vcpu(kvm, vpidx);

	if (vcpu && to_hv_vcpu(vcpu)->vp_index == vpidx)

	if (vcpu && kvm_hv_get_vpindex(vcpu) == vpidx)

		return vcpu;

	kvm_for_each_vcpu(i, vcpu, kvm)

		if (to_hv_vcpu(vcpu)->vp_index == vpidx)

		if (kvm_hv_get_vpindex(vcpu) == vpidx)

			return vcpu;

	return NULL;

}
@@ -377,9 +377,7 @@ static int syndbg_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host) 
		break;

	}



	trace_kvm_hv_syndbg_get_msr(vcpu->vcpu_id,

				    to_hv_vcpu(vcpu)->vp_index, msr,

				    *pdata);

	trace_kvm_hv_syndbg_get_msr(vcpu->vcpu_id, kvm_hv_get_vpindex(vcpu), msr, *pdata);



	return 0;

}
@@ -806,6 +804,9 @@ void kvm_hv_process_stimers(struct kvm_vcpu *vcpu) 
	u64 time_now, exp_time;

	int i;



	if (!hv_vcpu)

		return;



	for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)

		if (test_and_clear_bit(i, hv_vcpu->stimer_pending_bitmap)) {

			stimer = &hv_vcpu->stimer[i];
@@ -842,6 +843,9 @@ bool kvm_hv_assist_page_enabled(struct kvm_vcpu *vcpu) 
{

	struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);



	if (!hv_vcpu)

		return false;



	if (!(hv_vcpu->hv_vapic & HV_X64_MSR_VP_ASSIST_PAGE_ENABLE))

		return false;

	return vcpu->arch.pv_eoi.msr_val & KVM_MSR_ENABLED;
@@ -1504,8 +1508,7 @@ static __always_inline unsigned long *sparse_set_to_vcpu_mask( 


	bitmap_zero(vcpu_bitmap, KVM_MAX_VCPUS);

	kvm_for_each_vcpu(i, vcpu, kvm) {

		if (test_bit(to_hv_vcpu(vcpu)->vp_index,

			     (unsigned long *)vp_bitmap))

		if (test_bit(kvm_hv_get_vpindex(vcpu), (unsigned long *)vp_bitmap))

			__set_bit(i, vcpu_bitmap);

	}

	return vcpu_bitmap;

arch/x86/kvm/hyperv.h

+10 −0
Original line number Diff line number Diff line
@@ -83,6 +83,13 @@ static inline struct kvm_hv_syndbg *to_hv_syndbg(struct kvm_vcpu *vcpu) 
	return &vcpu->kvm->arch.hyperv.hv_syndbg;

}



static inline u32 kvm_hv_get_vpindex(struct kvm_vcpu *vcpu)

{

	struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);



	return hv_vcpu ? hv_vcpu->vp_index : kvm_vcpu_get_idx(vcpu);

}



int kvm_hv_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host);

int kvm_hv_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata, bool host);
@@ -121,6 +128,9 @@ static inline bool kvm_hv_has_stimer_pending(struct kvm_vcpu *vcpu) 
{

	struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);



	if (!hv_vcpu)

		return false;



	return !bitmap_empty(hv_vcpu->stimer_pending_bitmap,

			     HV_SYNIC_STIMER_COUNT);

}

arch/x86/kvm/lapic.c

+3 −2
Original line number Diff line number Diff line
@@ -1245,7 +1245,8 @@ static int apic_set_eoi(struct kvm_lapic *apic) 
	apic_clear_isr(vector, apic);

	apic_update_ppr(apic);



	if (test_bit(vector, to_hv_synic(apic->vcpu)->vec_bitmap))

	if (to_hv_vcpu(apic->vcpu) &&

	    test_bit(vector, to_hv_synic(apic->vcpu)->vec_bitmap))

		kvm_hv_synic_send_eoi(apic->vcpu, vector);



	kvm_ioapic_send_eoi(apic, vector);
@@ -2512,7 +2513,7 @@ int kvm_get_apic_interrupt(struct kvm_vcpu *vcpu) 
	 */



	apic_clear_irr(vector, apic);

	if (test_bit(vector, to_hv_synic(vcpu)->auto_eoi_bitmap)) {

	if (to_hv_vcpu(vcpu) && test_bit(vector, to_hv_synic(vcpu)->auto_eoi_bitmap)) {

		/*

		 * For auto-EOI interrupts, there might be another pending

		 * interrupt above PPR, so check whether to raise another

arch/x86/kvm/vmx/vmx.c

+1 −3
Original line number Diff line number Diff line
@@ -6810,12 +6810,10 @@ static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu) 


	/* All fields are clean at this point */

	if (static_branch_unlikely(&enable_evmcs)) {

		struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu);



		current_evmcs->hv_clean_fields |=

			HV_VMX_ENLIGHTENED_CLEAN_FIELD_ALL;



		current_evmcs->hv_vp_id = hv_vcpu->vp_index;

		current_evmcs->hv_vp_id = kvm_hv_get_vpindex(vcpu);

	}



	/* MSR_IA32_DEBUGCTLMSR is zeroed on vmexit. Restore it if needed */

arch/x86/kvm/x86.c

+5 −2
Original line number Diff line number Diff line
@@ -8803,8 +8803,11 @@ static void vcpu_load_eoi_exitmap(struct kvm_vcpu *vcpu) 
	if (!kvm_apic_hw_enabled(vcpu->arch.apic))

		return;



	bitmap_or((ulong *)eoi_exit_bitmap, vcpu->arch.ioapic_handled_vectors,

	if (to_hv_vcpu(vcpu))

		bitmap_or((ulong *)eoi_exit_bitmap,

			  vcpu->arch.ioapic_handled_vectors,

			  to_hv_synic(vcpu)->vec_bitmap, 256);



	static_call(kvm_x86_load_eoi_exitmap)(vcpu, eoi_exit_bitmap);

}