diff --git a/src/conf/capabilities.c b/src/conf/capabilities.c
index 0d2512e6af..575981cd35 100644
--- a/src/conf/capabilities.c
+++ b/src/conf/capabilities.c
@@ -65,12 +65,29 @@ virCapabilitiesNew(virArch hostarch,
     return caps;
 }
 
+void
+virCapabilitiesClearHostNUMACellCPUTopology(virCapsHostNUMACellCPUPtr cpus,
+                                            size_t ncpus)
+{
+    size_t i;
+
+    if (!cpus)
+        return;
+
+    for (i = 0; i < ncpus; i++) {
+        virBitmapFree(cpus[i].siblings);
+        cpus[i].siblings = NULL;
+    }
+}
+
 static void
 virCapabilitiesFreeHostNUMACell(virCapsHostNUMACellPtr cell)
 {
     if (cell == NULL)
         return;
 
+    virCapabilitiesClearHostNUMACellCPUTopology(cell->cpus, cell->ncpus);
+
     VIR_FREE(cell->cpus);
     VIR_FREE(cell);
 }
@@ -236,7 +253,7 @@ virCapabilitiesAddHostMigrateTransport(virCapsPtr caps,
  * @caps: capabilities to extend
  * @num: ID number of NUMA cell
  * @ncpus: number of CPUs in cell
- * @cpus: array of CPU ID numbers for cell
+ * @cpus: array of CPU definition structures, the pointer is stolen
  *
  * Registers a new NUMA cell for a host, passing in a
  * array of CPU IDs belonging to the cell
@@ -245,7 +262,7 @@ int
 virCapabilitiesAddHostNUMACell(virCapsPtr caps,
                                int num,
                                int ncpus,
-                               const int *cpus)
+                               virCapsHostNUMACellCPUPtr cpus)
 {
     virCapsHostNUMACellPtr cell;
 
@@ -256,16 +273,9 @@ virCapabilitiesAddHostNUMACell(virCapsPtr caps,
     if (VIR_ALLOC(cell) < 0)
         return -1;
 
-    if (VIR_ALLOC_N(cell->cpus, ncpus) < 0) {
-        VIR_FREE(cell);
-        return -1;
-    }
-    memcpy(cell->cpus,
-           cpus,
-           ncpus * sizeof(*cpus));
-
     cell->ncpus = ncpus;
     cell->num = num;
+    cell->cpus = cpus;
 
     caps->host.numaCell[caps->host.nnumaCell++] = cell;
 
@@ -693,7 +703,7 @@ virCapabilitiesFormatNUMATopology(virBufferPtr xml,
         virBufferAsprintf(xml, "          <cpus num='%d'>\n", cells[i]->ncpus);
         for (j = 0; j < cells[i]->ncpus; j++)
             virBufferAsprintf(xml, "            <cpu id='%d'/>\n",
-                              cells[i]->cpus[j]);
+                              cells[i]->cpus[j].id);
         virBufferAddLit(xml, "          </cpus>\n");
         virBufferAddLit(xml, "        </cell>\n");
     }
diff --git a/src/conf/capabilities.h b/src/conf/capabilities.h
index 19b99c6695..f5a5c4842f 100644
--- a/src/conf/capabilities.h
+++ b/src/conf/capabilities.h
@@ -84,12 +84,21 @@ struct _virCapsGuest {
     virCapsGuestFeaturePtr *features;
 };
 
+typedef struct _virCapsHostNUMACellCPU virCapsHostNUMACellCPU;
+typedef virCapsHostNUMACellCPU *virCapsHostNUMACellCPUPtr;
+struct _virCapsHostNUMACellCPU {
+    unsigned int id;
+    unsigned int socket_id;
+    unsigned int core_id;
+    virBitmapPtr siblings;
+};
+
 typedef struct _virCapsHostNUMACell virCapsHostNUMACell;
 typedef virCapsHostNUMACell *virCapsHostNUMACellPtr;
 struct _virCapsHostNUMACell {
     int num;
     int ncpus;
-    int *cpus;
+    virCapsHostNUMACellCPUPtr cpus;
 };
 
 typedef struct _virCapsHostSecModel virCapsHostSecModel;
@@ -201,7 +210,7 @@ extern int
 virCapabilitiesAddHostNUMACell(virCapsPtr caps,
                                int num,
                                int ncpus,
-                               const int *cpus);
+                               virCapsHostNUMACellCPUPtr cpus);
 
 
 extern int
@@ -250,6 +259,9 @@ virCapabilitiesSupportsGuestOSTypeArch(virCapsPtr caps,
                                        const char *ostype,
                                        virArch arch);
 
+void
+virCapabilitiesClearHostNUMACellCPUTopology(virCapsHostNUMACellCPUPtr cpu,
+                                            size_t ncpus);
 
 extern virArch
 virCapabilitiesDefaultGuestArch(virCapsPtr caps,
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index fc23adc181..42eae3e0dc 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -56,6 +56,7 @@ virCapabilitiesAddHostFeature;
 virCapabilitiesAddHostMigrateTransport;
 virCapabilitiesAddHostNUMACell;
 virCapabilitiesAllocMachines;
+virCapabilitiesClearHostNUMACellCPUTopology;
 virCapabilitiesDefaultGuestArch;
 virCapabilitiesDefaultGuestEmulator;
 virCapabilitiesDefaultGuestMachine;
diff --git a/src/nodeinfo.c b/src/nodeinfo.c
index 2cfd16c13e..c29769c853 100644
--- a/src/nodeinfo.c
+++ b/src/nodeinfo.c
@@ -1479,9 +1479,10 @@ nodeCapsInitNUMA(virCapsPtr caps)
     int n;
     unsigned long *mask = NULL;
     unsigned long *allonesmask = NULL;
-    int *cpus = NULL;
+    virCapsHostNUMACellCPUPtr cpus = NULL;
     int ret = -1;
     int max_n_cpus = NUMA_MAX_N_CPUS;
+    int ncpus = 0;
 
     if (numa_available() < 0)
         return 0;
@@ -1495,7 +1496,6 @@ nodeCapsInitNUMA(virCapsPtr caps)
 
     for (n = 0 ; n <= numa_max_node() ; n++) {
         int i;
-        int ncpus;
         /* The first time this returns -1, ENOENT if node doesn't exist... */
         if (numa_node_to_cpus(n, mask, mask_n_bytes) < 0) {
             VIR_WARN("NUMA topology for cell %d of %d not available, ignoring",
@@ -1518,20 +1518,17 @@ nodeCapsInitNUMA(virCapsPtr caps)
 
         for (ncpus = 0, i = 0 ; i < max_n_cpus ; i++)
             if (MASK_CPU_ISSET(mask, i))
-                cpus[ncpus++] = i;
+                cpus[ncpus++].id = i;
 
-        if (virCapabilitiesAddHostNUMACell(caps,
-                                           n,
-                                           ncpus,
-                                           cpus) < 0)
+        if (virCapabilitiesAddHostNUMACell(caps, n, ncpus, cpus) < 0)
             goto cleanup;
-
-        VIR_FREE(cpus);
+        cpus = NULL;
     }
 
     ret = 0;
 
 cleanup:
+    virCapabilitiesClearHostNUMACellCPUTopology(cpus, ncpus);
     VIR_FREE(cpus);
     VIR_FREE(mask);
     VIR_FREE(allonesmask);
diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c
index 55d00e33dc..a2ce007392 100644
--- a/src/qemu/qemu_process.c
+++ b/src/qemu/qemu_process.c
@@ -2032,7 +2032,7 @@ qemuPrepareCpumap(virQEMUDriverPtr driver,
             if (result) {
                 for (j = 0; j < cur_ncpus; j++)
                     ignore_value(virBitmapSetBit(cpumap,
-                                                 driver->caps->host.numaCell[i]->cpus[j]));
+                                                 driver->caps->host.numaCell[i]->cpus[j].id));
             }
         }
     }
diff --git a/src/test/test_driver.c b/src/test/test_driver.c
index a10a3770fb..6909fa46fa 100644
--- a/src/test/test_driver.c
+++ b/src/test/test_driver.c
@@ -69,7 +69,7 @@ typedef struct _testDomainObjPrivate *testDomainObjPrivatePtr;
 struct _testCell {
     unsigned long mem;
     int numCpus;
-    int cpus[MAX_CPUS];
+    virCapsHostNUMACellCPU cpus[MAX_CPUS];
 };
 typedef struct _testCell testCell;
 typedef struct _testCell *testCellPtr;
@@ -174,8 +174,17 @@ testBuildCapabilities(virConnectPtr conn) {
         goto no_memory;
 
     for (i = 0; i < privconn->numCells; i++) {
+        virCapsHostNUMACellCPUPtr cpu_cells;
+
+        if (VIR_ALLOC_N(cpu_cells, privconn->cells[i].numCpus) < 0)
+            goto no_memory;
+
+        memcpy(cpu_cells, privconn->cells[i].cpus,
+               sizeof(*cpu_cells) * privconn->cells[i].numCpus);
+
+
         if (virCapabilitiesAddHostNUMACell(caps, i, privconn->cells[i].numCpus,
-                                           privconn->cells[i].cpus) < 0)
+                                           cpu_cells) < 0)
             goto no_memory;
     }
 
@@ -549,7 +558,7 @@ static int testOpenDefault(virConnectPtr conn) {
         privconn->cells[u].mem = (u + 1) * 2048 * 1024;
     }
     for (u = 0 ; u < 16 ; u++) {
-        privconn->cells[u % 2].cpus[(u / 2)] = u;
+        privconn->cells[u % 2].cpus[(u / 2)].id = u;
     }
 
     if (!(privconn->caps = testBuildCapabilities(conn)))
diff --git a/src/xen/xend_internal.c b/src/xen/xend_internal.c
index 00d1c9bbd8..d0e54a8f9c 100644
--- a/src/xen/xend_internal.c
+++ b/src/xen/xend_internal.c
@@ -1112,7 +1112,7 @@ sexpr_to_xend_topology(const struct sexpr *root,
 {
     const char *nodeToCpu;
     const char *cur;
-    int *cpuNums = NULL;
+    virCapsHostNUMACellCPUPtr cpuInfo = NULL;
     int cell, cpu, nb_cpus;
     int n = 0;
     int numCpus;
@@ -1124,9 +1124,6 @@ sexpr_to_xend_topology(const struct sexpr *root,
     numCpus = sexpr_int(root, "node/nr_cpus");
 
 
-    if (VIR_ALLOC_N(cpuNums, numCpus) < 0)
-        goto memory_error;
-
     cur = nodeToCpu;
     while (*cur != 0) {
         virBitmapPtr cpuset = NULL;
@@ -1155,31 +1152,35 @@ sexpr_to_xend_topology(const struct sexpr *root,
                 goto error;
         }
 
+        if (VIR_ALLOC_N(cpuInfo, numCpus) < 0)
+            goto memory_error;
+
         for (n = 0, cpu = 0; cpu < numCpus; cpu++) {
             bool used;
 
             ignore_value(virBitmapGetBit(cpuset, cpu, &used));
             if (used)
-                cpuNums[n++] = cpu;
+                cpuInfo[n++].id = cpu;
         }
         virBitmapFree(cpuset);
 
-        if (virCapabilitiesAddHostNUMACell(caps, cell, nb_cpus, cpuNums) < 0)
+        if (virCapabilitiesAddHostNUMACell(caps, cell, nb_cpus, cpuInfo) < 0)
             goto memory_error;
+        cpuInfo = NULL;
     }
-    VIR_FREE(cpuNums);
+
     return 0;
 
   parse_error:
     virReportError(VIR_ERR_XEN_CALL, "%s", _("topology syntax error"));
   error:
-    VIR_FREE(cpuNums);
+    virCapabilitiesClearHostNUMACellCPUTopology(cpuInfo, nb_cpus);
+    VIR_FREE(cpuInfo);
     return -1;
 
   memory_error:
-    VIR_FREE(cpuNums);
     virReportOOMError();
-    return -1;
+    goto error;
 }