[RFC PATCH v3 03/19] KVM: x86: SVM: remove avic's broken code that updated APIC ID

From: Maxim Levitsky
Date: Wed Apr 27 2022 - 16:04:14 EST


AVIC is now inhibited if the guest changes apic id, thus remove
that broken code.

Signed-off-by: Maxim Levitsky <mlevitsk@xxxxxxxxxx>
---
arch/x86/kvm/svm/avic.c | 35 -----------------------------------
1 file changed, 35 deletions(-)

diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c
index 54fe03714f8a6..1102421668a11 100644
--- a/arch/x86/kvm/svm/avic.c
+++ b/arch/x86/kvm/svm/avic.c
@@ -508,35 +508,6 @@ static int avic_handle_ldr_update(struct kvm_vcpu *vcpu)
return ret;
}

-static int avic_handle_apic_id_update(struct kvm_vcpu *vcpu)
-{
- u64 *old, *new;
- struct vcpu_svm *svm = to_svm(vcpu);
- u32 id = kvm_xapic_id(vcpu->arch.apic);
-
- if (vcpu->vcpu_id == id)
- return 0;
-
- old = avic_get_physical_id_entry(vcpu, vcpu->vcpu_id);
- new = avic_get_physical_id_entry(vcpu, id);
- if (!new || !old)
- return 1;
-
- /* We need to move physical_id_entry to new offset */
- *new = *old;
- *old = 0ULL;
- to_svm(vcpu)->avic_physical_id_cache = new;
-
- /*
- * Also update the guest physical APIC ID in the logical
- * APIC ID table entry if already setup the LDR.
- */
- if (svm->ldr_reg)
- avic_handle_ldr_update(vcpu);
-
- return 0;
-}
-
static void avic_handle_dfr_update(struct kvm_vcpu *vcpu)
{
struct vcpu_svm *svm = to_svm(vcpu);
@@ -555,10 +526,6 @@ static int avic_unaccel_trap_write(struct kvm_vcpu *vcpu)
AVIC_UNACCEL_ACCESS_OFFSET_MASK;

switch (offset) {
- case APIC_ID:
- if (avic_handle_apic_id_update(vcpu))
- return 0;
- break;
case APIC_LDR:
if (avic_handle_ldr_update(vcpu))
return 0;
@@ -650,8 +617,6 @@ int avic_init_vcpu(struct vcpu_svm *svm)

void avic_apicv_post_state_restore(struct kvm_vcpu *vcpu)
{
- if (avic_handle_apic_id_update(vcpu) != 0)
- return;
avic_handle_dfr_update(vcpu);
avic_handle_ldr_update(vcpu);
}
--
2.26.3