diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index b677d1b13e..2ae459453d 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -411,15 +411,21 @@ static int kvm_slot_update_flags(KVMMemoryListener *kml, KVMSlot *mem,
 static int kvm_section_update_flags(KVMMemoryListener *kml,
                                     MemoryRegionSection *section)
 {
-    hwaddr phys_addr = section->offset_within_address_space;
-    ram_addr_t size = int128_get64(section->size);
-    KVMSlot *mem = kvm_lookup_matching_slot(kml, phys_addr, size);
+    hwaddr start_addr, size;
+    KVMSlot *mem;
 
-    if (mem == NULL)  {
+    size = kvm_align_section(section, &start_addr);
+    if (!size) {
         return 0;
-    } else {
-        return kvm_slot_update_flags(kml, mem, section->mr);
     }
+
+    mem = kvm_lookup_matching_slot(kml, start_addr, size);
+    if (!mem) {
+        fprintf(stderr, "%s: error finding slot\n", __func__);
+        abort();
+    }
+
+    return kvm_slot_update_flags(kml, mem, section->mr);
 }
 
 static void kvm_log_start(MemoryListener *listener,