From: Julia Lawall <julia@xxxxxxx> As noted by Akinobu Mita in patch b1fceac2b9e04d278316b2faddf276015fc06e3b, alloc_bootmem and related functions never return NULL and always return a zeroed region of memory. Thus a NULL test or memset after calls to these functions is unnecessary. This was fixed using the following semantic patch. (http://www.emn.fr/x-info/coccinelle/) // <smpl> @@ expression E; statement S; @@ E = \(alloc_bootmem\|alloc_bootmem_low\|alloc_bootmem_pages\|alloc_bootmem_low_pages\|alloc_bootmem_node\|alloc_bootmem_low_pages_node\|alloc_bootmem_pages_node\)(...) ... when != E ( - BUG_ON (E == NULL); | - if (E == NULL) S ) @@ expression E,E1; @@ E = \(alloc_bootmem\|alloc_bootmem_low\|alloc_bootmem_pages\|alloc_bootmem_low_pages\|alloc_bootmem_node\|alloc_bootmem_low_pages_node\|alloc_bootmem_pages_node\)(...) ... when != E - memset(E,0,E1); // </smpl> Signed-off-by: Julia Lawall <julia@xxxxxxx> --- mm/page_alloc.c | 4 +--- 1 files changed, 1 insertions(+), 3 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index d8ac014..5040299 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -3381,10 +3381,8 @@ static void __init setup_usemap(struct pglist_data *pgdat, { unsigned long usemapsize = usemap_size(zonesize); zone->pageblock_flags = NULL; - if (usemapsize) { + if (usemapsize) zone->pageblock_flags = alloc_bootmem_node(pgdat, usemapsize); - memset(zone->pageblock_flags, 0, usemapsize); - } } #else static void inline setup_usemap(struct pglist_data *pgdat, -- To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html