KVM does not support changing the APIC's base address. Prior to commit
3743c2f02517 ("KVM: x86: inhibit APICv/AVIC on changes to APIC ID or
APIC base"), it emitted a rate-limited warning about this. Now, it's
just silently broken.
Use vcpu_unimpl() to complain about this unsupported operation. Even a
rate-limited error message is better than complete silence.
Fixes: 3743c2f02517 ("KVM: x86: inhibit APICv/AVIC on changes to APIC ID or APIC base")
Signed-off-by: Jim Mattson <jmattson@xxxxxxxxxx>
---
Changes in v2:
* Changed format specifiers from "%#llx" to "%#x"
* Cast apic->base_address to unsigned int for printing
arch/x86/kvm/lapic.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index acd7d48100a1..43ac05d10b2e 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -2583,6 +2583,9 @@ void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value)
if ((value & MSR_IA32_APICBASE_ENABLE) &&
apic->base_address != APIC_DEFAULT_PHYS_BASE) {
+ vcpu_unimpl(vcpu, "APIC base %#x is not %#x",
+ (unsigned int)apic->base_address,
+ APIC_DEFAULT_PHYS_BASE);
kvm_set_apicv_inhibit(apic->vcpu->kvm,
APICV_INHIBIT_REASON_APIC_BASE_MODIFIED);
}
--
2.45.2.741.gdbec12cfda-goog
