KVM: arm64: Mark freed S2 MMUs as invalid

When freeing an S2 MMU, we free the associated pgd, but omit to mark the structure as invalid. Subsequently, a call to kvm_nested_s2_unmap() would pick these invalid S2 MMUs and pass them down the teardown path.

This ends up with a nasty warning as we try to unmap an unallocated set of page tables.

Fix this by making the S2 MMU invalid on freeing the pgd by calling kvm_init_nested_s2_mmu().

---
 arch/arm64/kvm/mmu.c | 4 ++++
 1 file changed, 4 insertions(+)

index 9a45daf817bf..315aaadfda30 100644
@@ -1074,6 +1074,10 @@ void kvm_free_stage2_pgd(struct kvm_s2_mmu *mmu)
 		mmu->pgt = NULL;
 		free_percpu(mmu->last_vcpu_ran);
 	}
+
+	if (kvm_is_nested_s2_mmu(kvm, mmu))
+		kvm_init_nested_s2_mmu(mmu);
+		
 	write_unlock(&kvm->mmu_lock);
 
 	if (pgt) {

2.47.2

Applied to fixes, thanks!

[1/1] KVM: arm64: Mark freed S2 MMUs as invalid

      https://git.kernel.org/kvmarm/kvmarm/c/34b8f4adedd5

--
Best,
Oliver