From: Mike Rapoport <rppt@xxxxxxxxxxxxx> Subject: mm/page_alloc.c: check return value of memblock_alloc_node_nopanic() There are two early memory allocations that use memblock_alloc_node_nopanic() and do not check its return value. While this happens very early during boot and chances that the allocation will fail are diminishing, it is still worth to have proper checks for the allocation errors. Link: http://lkml.kernel.org/r/1547734941-944-1-git-send-email-rppt@xxxxxxxxxxxxx Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxx> Reviewed-by: William Kucharski <william.kucharski@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/page_alloc.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) --- a/mm/page_alloc.c~mm-page_alloc-check-return-value-of-memblock_alloc_node_nopanic +++ a/mm/page_alloc.c @@ -6431,10 +6431,14 @@ static void __ref setup_usemap(struct pg { unsigned long usemapsize = usemap_size(zone_start_pfn, zonesize); zone->pageblock_flags = NULL; - if (usemapsize) + if (usemapsize) { zone->pageblock_flags = memblock_alloc_node_nopanic(usemapsize, pgdat->node_id); + if (!zone->pageblock_flags) + panic("Failed to allocate %ld bytes for zone %s pageblock flags on node %d\n", + usemapsize, zone->name, pgdat->node_id); + } } #else static inline void setup_usemap(struct pglist_data *pgdat, struct zone *zone, @@ -6664,6 +6668,9 @@ static void __ref alloc_node_mem_map(str end = ALIGN(end, MAX_ORDER_NR_PAGES); size = (end - start) * sizeof(struct page); map = memblock_alloc_node_nopanic(size, pgdat->node_id); + if (!map) + panic("Failed to allocate %ld bytes for node %d memory map\n", + size, pgdat->node_id); pgdat->node_mem_map = map + offset; } pr_debug("%s: node %d, pgdat %08lx, node_mem_map %08lx\n", _
