xen/arm: make_memory_node return error on nr_banks == 0

Call make_memory_node for reserved_memory only if we actually have any
reserved_memory regions to handle.

Add a check in make_memory_node to return an error if it has been called
with no memory banks as argument.

Fixes: 248faa637d2 (xen/arm: add reserved-memory regions to the dom0 memory node)
Signed-off-by: Stefano Stabellini <stefano.stabellini@xilinx.com>
Acked-by: Julien Grall <julien.grall@arm.com>
Release-acked-by: Juergen Gross <jgross@suse.com>

diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
index 921b0545202a52c990eb6dc50123bbcced004538..5ab84e583931cac2252e921bb9dd3a12d3d52ec6 100644 (file)
--- a/xen/arch/arm/domain_build.c
+++ b/xen/arch/arm/domain_build.c
@@ -650,6 +650,8 @@ static int __init make_memory_node(const struct domain *d,
     __be32 *cells;
 
     BUG_ON(nr_cells >= ARRAY_SIZE(reg));
+    if ( mem->nr_banks == 0 )
+        return -ENOENT;
 
     dt_dprintk("Create memory node (reg size %d, nr cells %d)\n",
                reg_size, nr_cells);
@@ -1540,10 +1542,13 @@ static int __init handle_node(struct domain *d, struct kernel_info *kinfo,
          * Create a second memory node to store the ranges covering
          * reserved-memory regions.
          */
-        res = make_memory_node(d, kinfo->fdt, addrcells, sizecells,
-                               &bootinfo.reserved_mem);
-        if ( res )
-            return res;
+        if ( bootinfo.reserved_mem.nr_banks > 0 )
+        {
+            res = make_memory_node(d, kinfo->fdt, addrcells, sizecells,
+                                   &bootinfo.reserved_mem);
+            if ( res )
+                return res;
+        }
     }
 
     res = fdt_end_node(kinfo->fdt);