X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=mm%2Fsparse.c;h=98d6b39c34722c1734bee587a612ce0f74d7fbfa;hb=0b79dada976198cb1a4c043068e3b44d5cab2a5a;hp=f6a43c09c322cdb39077392ec1c77e9904c52d82;hpb=1f7d4f8395093021ed2262296179cfe71bd5e2ec;p=linux-2.6

diff --git a/mm/sparse.c b/mm/sparse.c
index f6a43c09c3..98d6b39c34 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -149,8 +149,18 @@ static inline int sparse_early_nid(struct mem_section *section)
 /* Record a memory area against a node. */
 void __init memory_present(int nid, unsigned long start, unsigned long end)
 {
+	unsigned long max_arch_pfn = 1UL << (MAX_PHYSMEM_BITS-PAGE_SHIFT);
 	unsigned long pfn;
 
+	/*
+	 * Sanity checks - do not allow an architecture to pass
+	 * in larger pfns than the maximum scope of sparsemem:
+	 */
+	if (start >= max_arch_pfn)
+		return;
+	if (end >= max_arch_pfn)
+		end = max_arch_pfn;
+
 	start &= PAGE_SECTION_MASK;
 	for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION) {
 		unsigned long section = pfn_to_section_nr(pfn);