[RFC PATCH 3/8] KVM: x86: Add callback functions for handling APIC ID, DFR and LDR update

["Suthikulpanit, Suravee" <Suravee.Suthikulpanit@xxxxxxx>]

Add hooks for handling the case when guest VM update APIC ID, DFR and LDR.
This is needed during when AMD AVIC is temporary deactivated.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
---
 arch/x86/include/asm/kvm_host.h |  3 +++
 arch/x86/kvm/lapic.c            | 11 +++++++++--
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 05b5778c769e..cad47b4955e2 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1083,6 +1083,9 @@ struct kvm_x86_ops {
 	void (*refresh_apicv_exec_ctrl)(struct kvm_vcpu *vcpu);
 	void (*hwapic_irr_update)(struct kvm_vcpu *vcpu, int max_irr);
 	void (*hwapic_isr_update)(struct kvm_vcpu *vcpu, int isr);
+	void (*hwapic_apic_id_update)(struct kvm_vcpu *vcpu);
+	void (*hwapic_dfr_update)(struct kvm_vcpu *vcpu);
+	void (*hwapic_ldr_update)(struct kvm_vcpu *vcpu);
 	bool (*guest_apic_has_interrupt)(struct kvm_vcpu *vcpu);
 	void (*load_eoi_exitmap)(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap);
 	void (*set_virtual_apic_mode)(struct kvm_vcpu *vcpu);
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 9f089e2e09d0..a067a7292a5f 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -267,6 +267,8 @@ static inline void kvm_apic_set_xapic_id(struct kvm_lapic *apic, u8 id)
 static inline void kvm_apic_set_ldr(struct kvm_lapic *apic, u32 id)
 {
 	kvm_lapic_set_reg(apic, APIC_LDR, id);
+	if (kvm_x86_ops->hwapic_ldr_update)
+		kvm_x86_ops->hwapic_ldr_update(apic->vcpu);
 	recalculate_apic_map(apic->vcpu->kvm);
 }
 
@@ -1809,10 +1811,13 @@ int kvm_lapic_reg_write(struct kvm_lapic *apic, u32 reg, u32 val)
 
 	switch (reg) {
 	case APIC_ID:		/* Local APIC ID */
-		if (!apic_x2apic_mode(apic))
+		if (!apic_x2apic_mode(apic)) {
 			kvm_apic_set_xapic_id(apic, val >> 24);
-		else
+			if (kvm_x86_ops->hwapic_apic_id_update)
+				kvm_x86_ops->hwapic_apic_id_update(apic->vcpu);
+		} else {
 			ret = 1;
+		}
 		break;
 
 	case APIC_TASKPRI:
@@ -1834,6 +1839,8 @@ int kvm_lapic_reg_write(struct kvm_lapic *apic, u32 reg, u32 val)
 	case APIC_DFR:
 		if (!apic_x2apic_mode(apic)) {
 			kvm_lapic_set_reg(apic, APIC_DFR, val | 0x0FFFFFFF);
+			if (kvm_x86_ops->hwapic_dfr_update)
+				kvm_x86_ops->hwapic_dfr_update(apic->vcpu);
 			recalculate_apic_map(apic->vcpu->kvm);
 		} else
 			ret = 1;
-- 
2.17.1