KVM: arm/arm64: Handle hva aging while destroying the vm

The mmu_notifier_release() callback of KVM triggers cleaning up the stage2 page table on kvm-arm. However there could be other notifier callbacks in parallel with the mmu_notifier_release(), which could cause the call backs ending up in an empty stage2 page table. Make sure we check it for all the notifier callbacks. Cc: [email protected] Fixes: commit 293f293 ("kvm-arm: Unmap shadow pagetables properly") Reported-by: Alex Graf <[email protected]> Reviewed-by: Christoffer Dall <[email protected]> Signed-off-by: Suzuki K Poulose <[email protected]> Signed-off-by: Marc Zyngier <[email protected]>
opendata26 · Jul 25, 2017 · 7e5a672 · 7e5a672
1 parent d9f89b4
commit 7e5a672
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c
@@ -1718,12 +1718,16 @@ static int kvm_test_age_hva_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *
 
 int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end)
 {
+	if (!kvm->arch.pgd)
+		return 0;
 	trace_kvm_age_hva(start, end);
 	return handle_hva_to_gpa(kvm, start, end, kvm_age_hva_handler, NULL);
 }
 
 int kvm_test_age_hva(struct kvm *kvm, unsigned long hva)
 {
+	if (!kvm->arch.pgd)
+		return 0;
 	trace_kvm_test_age_hva(hva);
 	return handle_hva_to_gpa(kvm, hva, hva, kvm_test_age_hva_handler, NULL);
 }