diff options
Diffstat (limited to 'mm/sparse.c')
| -rw-r--r-- | mm/sparse.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/mm/sparse.c b/mm/sparse.c index 2609aba121e8..6b8b5e91ceef 100644 --- a/mm/sparse.c +++ b/mm/sparse.c @@ -264,7 +264,11 @@ unsigned long __init node_memmap_size_bytes(int nid, unsigned long start_pfn, */ static unsigned long sparse_encode_mem_map(struct page *mem_map, unsigned long pnum) { - return (unsigned long)(mem_map - (section_nr_to_pfn(pnum))); + unsigned long coded_mem_map = + (unsigned long)(mem_map - (section_nr_to_pfn(pnum))); + BUILD_BUG_ON(SECTION_MAP_LAST_BIT > (1UL<<PFN_SECTION_SHIFT)); + BUG_ON(coded_mem_map & ~SECTION_MAP_MASK); + return coded_mem_map; } /* |