[PATCH] enable booting a NUMA system where some nodes have no memory
When booting a NUMA system with nodes that have no memory (eg by limiting
memory), bootmem_alloc_core tried to find pages in an uninitialized
bootmem_map. This caused a null pointer access. This fix adds a check, so
that NULL is returned. That will enable the caller (bootmem_alloc_nopanic)
to alloc memory on other without a panic.
Signed-off-by: Christian Krafft <krafft@de.ibm.com>
Cc: Christoph Lameter <clameter@engr.sgi.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Martin Bligh <mbligh@google.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/mm/bootmem.c b/mm/bootmem.c
index d53112fc..9425342 100644
--- a/mm/bootmem.c
+++ b/mm/bootmem.c
@@ -196,6 +196,10 @@
if (limit && bdata->node_boot_start >= limit)
return NULL;
+ /* on nodes without memory - bootmem_map is NULL */
+ if (!bdata->node_bootmem_map)
+ return NULL;
+
end_pfn = bdata->node_low_pfn;
limit = PFN_DOWN(limit);
if (limit && end_pfn > limit)