Merge tag 'regmap-3.4' into regmap-stride

regmap: Last minute bug fix for 3.4

This is a last minute bug fix that was only just noticed since the code
path that's being exercised here is one that is fairly rarely used.  The
changelog for the change itself is extremely clear and the code itself
is obvious to inspection so should be pretty safe.

Conflicts:
	drivers/base/regmap/regmap.c (overlap between the fix and stride code)

1 files changed, 21 insertions, 9 deletions

diff --git a/virt/kvm/iommu.c b/virt/kvm/iommu.c
index a457d2138f4..e9fff9830bf 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;
 }