diff options
| -rw-r--r-- | mm/memory_hotplug.c | 22 |
1 files changed, 18 insertions, 4 deletions
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 729fba144c71..b8467faf2f69 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -838,9 +838,16 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int ret; struct memory_notify arg; - /* We can only online full sections (e.g., SECTION_IS_ONLINE) */ + /* + * {on,off}lining is constrained to full memory sections (or more + * precisly to memory blocks from the user space POV). + * memmap_on_memory is an exception because it reserves initial part + * of the physical memory space for vmemmaps. That space is pageblock + * aligned. + */ if (WARN_ON_ONCE(!nr_pages || - !IS_ALIGNED(pfn | nr_pages, PAGES_PER_SECTION))) + !IS_ALIGNED(pfn, pageblock_nr_pages) || + !IS_ALIGNED(pfn + nr_pages, PAGES_PER_SECTION))) return -EINVAL; mem_hotplug_begin(); @@ -1573,9 +1580,16 @@ int __ref offline_pages(unsigned long start_pfn, unsigned long nr_pages) int ret, node; char *reason; - /* We can only offline full sections (e.g., SECTION_IS_ONLINE) */ + /* + * {on,off}lining is constrained to full memory sections (or more + * precisly to memory blocks from the user space POV). + * memmap_on_memory is an exception because it reserves initial part + * of the physical memory space for vmemmaps. That space is pageblock + * aligned. + */ if (WARN_ON_ONCE(!nr_pages || - !IS_ALIGNED(start_pfn | nr_pages, PAGES_PER_SECTION))) + !IS_ALIGNED(start_pfn, pageblock_nr_pages) || + !IS_ALIGNED(start_pfn + nr_pages, PAGES_PER_SECTION))) return -EINVAL; mem_hotplug_begin(); |