__nr_to_section() may return a null pointer, before accessing the member variable section_mem_map, we should first determine whether it is a null pointer. Signed-off-by: Liam Ni <zhiguangni01@xxxxxxxxx> --- mm/sparse.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/sparse.c b/mm/sparse.c index 4e6e3a9d49dc..37fa3818bc25 100644 --- a/mm/sparse.c +++ b/mm/sparse.c @@ -258,7 +258,7 @@ static void __init memory_present(int nid, unsigned long start, unsigned long en set_section_nid(section, nid); ms = __nr_to_section(section); - if (!ms->section_mem_map) { + if (ms && !ms->section_mem_map) { ms->section_mem_map = sparse_encode_early_nid(nid) | SECTION_IS_ONLINE; __section_mark_present(ms, section); -- 2.25.1