kvm: Obey read-only mappings in iommu

We've been ignoring read-only mappings and programming everything into the iommu as read-write. Fix this to only include the write access flag when read-only is not set. Signed-off-by: Alex Williamson <[email protected]> Signed-off-by: Gleb Natapov <[email protected]>
powerwareeasyman · Jan 27, 2013 · d47510e · d47510e
1 parent 261874b
commit d47510e
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/virt/kvm/iommu.c b/virt/kvm/iommu.c
@@ -76,7 +76,9 @@ int kvm_iommu_map_pages(struct kvm *kvm, struct kvm_memory_slot *slot)
 	gfn     = slot->base_gfn;
 	end_gfn = gfn + slot->npages;
 
-	flags = IOMMU_READ | IOMMU_WRITE;
+	flags = IOMMU_READ;
+	if (!(slot->flags & KVM_MEM_READONLY))
+		flags |= IOMMU_WRITE;
 	if (kvm->arch.iommu_flags & KVM_IOMMU_CACHE_COHERENCY)
 		flags |= IOMMU_CACHE;