2 files changed, 24 insertions, 11 deletions

diff --git a/virt/kvm/iommu.c b/virt/kvm/iommu.c
index a457d2138f49..e9fff9830bf0 100644
--- a/virt/kvm/iommu.c
+++ b/virt/kvm/iommu.c
@@ -240,9 +240,13 @@ int kvm_iommu_map_guest(struct kvm *kvm)
                 return -ENODEV;
         }
 
+        mutex_lock(&kvm->slots_lock);
+
         kvm->arch.iommu_domain = iommu_domain_alloc(&pci_bus_type);
-        if (!kvm->arch.iommu_domain)
-                return -ENOMEM;
+        if (!kvm->arch.iommu_domain) {
+                r = -ENOMEM;
+                goto out_unlock;
+        }
 
         if (!allow_unsafe_assigned_interrupts &&
             !iommu_domain_has_cap(kvm->arch.iommu_domain,
@@ -253,17 +257,16 @@ int kvm_iommu_map_guest(struct kvm *kvm)
                        " module option.\n", __func__);
                 iommu_domain_free(kvm->arch.iommu_domain);
                 kvm->arch.iommu_domain = NULL;
-                return -EPERM;
+                r = -EPERM;
+                goto out_unlock;
         }
 
         r = kvm_iommu_map_memslots(kvm);
         if (r)
-                goto out_unmap;
-
-        return 0;
+                kvm_iommu_unmap_memslots(kvm);
 
-out_unmap:
-        kvm_iommu_unmap_memslots(kvm);
+out_unlock:
+        mutex_unlock(&kvm->slots_lock);
         return r;
 }
 
@@ -310,6 +313,11 @@ static void kvm_iommu_put_pages(struct kvm *kvm,
         }
 }
 
+void kvm_iommu_unmap_pages(struct kvm *kvm, struct kvm_memory_slot *slot)
+{
+        kvm_iommu_put_pages(kvm, slot->base_gfn, slot->npages);
+}
+
 static int kvm_iommu_unmap_memslots(struct kvm *kvm)
 {
         int idx;
@@ -320,7 +328,7 @@ static int kvm_iommu_unmap_memslots(struct kvm *kvm)
         slots = kvm_memslots(kvm);
 
         kvm_for_each_memslot(memslot, slots)
-                kvm_iommu_put_pages(kvm, memslot->base_gfn, memslot->npages);
+                kvm_iommu_unmap_pages(kvm, memslot);
 
         srcu_read_unlock(&kvm->srcu, idx);
 
@@ -335,7 +343,11 @@ int kvm_iommu_unmap_guest(struct kvm *kvm)
         if (!domain)
                 return 0;
 
+        mutex_lock(&kvm->slots_lock);
         kvm_iommu_unmap_memslots(kvm);
+        kvm->arch.iommu_domain = NULL;
+        mutex_unlock(&kvm->slots_lock);
+
         iommu_domain_free(domain);
         return 0;
 }
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 42b73930a6de..9739b533ca2e 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -808,12 +808,13 @@ int __kvm_set_memory_region(struct kvm *kvm,
         if (r)
                 goto out_free;
 
-        /* map the pages in iommu page table */
+        /* map/unmap the pages in iommu page table */
         if (npages) {
                 r = kvm_iommu_map_pages(kvm, &new);
                 if (r)
                         goto out_free;
-        }
+        } else
+                kvm_iommu_unmap_pages(kvm, &old);
 
         r = -ENOMEM;
         slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots),