By converting start and size to page granularity, we actually ignore unaligned parts within a page instead of properly bailing out with an error. Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Oscar Salvador <osalvador@xxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: David Hildenbrand <david@xxxxxxxxxx> Cc: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx> Cc: Qian Cai <cai@xxxxxx> Cc: Wei Yang <richard.weiyang@xxxxxxxxx> Cc: Arun KS <arunks@xxxxxxxxxxxxxx> Cc: Mathieu Malaterre <malat@xxxxxxxxxx> Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> --- mm/memory_hotplug.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 328878b6799d..202febe88b58 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1050,16 +1050,11 @@ int try_online_node(int nid) static int check_hotplug_memory_range(u64 start, u64 size) { - unsigned long block_sz = memory_block_size_bytes(); - u64 block_nr_pages = block_sz >> PAGE_SHIFT; - u64 nr_pages = size >> PAGE_SHIFT; - u64 start_pfn = PFN_DOWN(start); - /* memory range must be block size aligned */ - if (!nr_pages || !IS_ALIGNED(start_pfn, block_nr_pages) || - !IS_ALIGNED(nr_pages, block_nr_pages)) { + if (!size || !IS_ALIGNED(start, memory_block_size_bytes()) || + !IS_ALIGNED(size, memory_block_size_bytes())) { pr_err("Block size [%#lx] unaligned hotplug range: start %#llx, size %#llx", - block_sz, start, size); + memory_block_size_bytes(), start, size); return -EINVAL; } -- 2.20.1