diff options
| author | Oscar Salvador <osalvador@suse.de> | 2021-05-04 18:39:36 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-05-05 11:27:26 -0700 |
| commit | dd8e2f230d82ecd60504fba48bb10bf3760b674e (patch) | |
| tree | c067c9fd2f962a71f017d76705024ae126a389d8 | |
| parent | 8736cc2d002f14e90d2b33bc5bef1740f6275ba4 (diff) | |
mm,memory_hotplug: relax fully spanned sections check
We want {online,offline}_pages to operate on whole memblocks, but
memmap_on_memory will poke pageblock_nr_pages aligned holes in the
beginning, which is a special case we want to allow. Relax the check to
account for that case.
Link: https://lkml.kernel.org/r/20210421102701.25051-3-osalvador@suse.de
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -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(); |