[Qemu-devel] [PATCH v2] pc-dimm: fix error messages if no slots were defined

[David Hildenbrand <david@redhat.com>]

If no slots were defined we try to allocate an empty bitmap, which
fails.

Signed-off-by: David Hildenbrand <david@redhat.com>
---

v1 -> v2: more detailed error message

 hw/mem/pc-dimm.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/hw/mem/pc-dimm.c b/hw/mem/pc-dimm.c
index 0119c68e01..12da89d562 100644
--- a/hw/mem/pc-dimm.c
+++ b/hw/mem/pc-dimm.c
@@ -118,9 +118,16 @@ static int pc_dimm_slot2bitmap(Object *obj, void *opaque)
 
 int pc_dimm_get_free_slot(const int *hint, int max_slots, Error **errp)
 {
-    unsigned long *bitmap = bitmap_new(max_slots);
+    unsigned long *bitmap;
     int slot = 0;
 
+    if (max_slots <= 0) {
+        error_setg(errp, "no slots where allocated, please specify "
+                   "the 'slots' option");
+        return slot;
+    }
+
+    bitmap = bitmap_new(max_slots);
     object_child_foreach(qdev_get_machine(), pc_dimm_slot2bitmap, bitmap);
 
     /* check if requested slot is not occupied */
-- 
2.14.3