The patch titled
Subject: mm/memory_hotplug: handle unaligned start and nr_pages in online_pages_blocks()
has been added to the -mm tree. Its filename is
mm-memory_hotplug-handle-unaligned-start-and-nr_pages-in-online_pages_blocks.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-memory_hotplug-handle-unaligned-start-and-nr_pages-in-online_pages_blocks.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-memory_hotplug-handle-unaligned-start-and-nr_pages-in-online_pages_blocks.patch
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------------------------------------------------------
From: David Hildenbrand <david@xxxxxxxxxx>
Subject: mm/memory_hotplug: handle unaligned start and nr_pages in online_pages_blocks()
Take care of nr_pages not being a power of two and start not being
properly aligned. Essentially, what walk_system_ram_range() could provide
to us. get_order() will round-up in case it's not a power of two.
This should only apply to memory blocks that contain strange memory
resources (especially with holes), not to ordinary DIMMs.
Link: http://lkml.kernel.org/r/20190809125701.3316-3-david@xxxxxxxxxx
Fixes-no-stable: a9cd410a3d29 ("mm/page_alloc.c: memory hotplug: free pages as higher order")
Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
Cc: Arun KS <arunks@xxxxxxxxxxxxxx>
Cc: Oscar Salvador <osalvador@xxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx>
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Nadav Amit <namit@xxxxxxxxxx>
Cc: Wei Yang <richardw.yang@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/memory_hotplug.c | 4 ++++
1 file changed, 4 insertions(+)
--- a/mm/memory_hotplug.c~mm-memory_hotplug-handle-unaligned-start-and-nr_pages-in-online_pages_blocks
+++ a/mm/memory_hotplug.c
@@ -640,6 +640,10 @@ static int online_pages_blocks(unsigned
while (start < end) {
order = min(MAX_ORDER - 1,
get_order(PFN_PHYS(end) - PFN_PHYS(start)));
+ /* make sure the PFN is aligned and we don't exceed the range */
+ while (!IS_ALIGNED(start, 1ul << order) ||
+ (1ul << order) > end - start)
+ order--;
(*online_page_callback)(pfn_to_page(start), order);
onlined_pages += (1UL << order);
_
Patches currently in -mm which might be from david@xxxxxxxxxx are
mm-memory_hotplug-remove-move_pfn_range.patch
drivers-base-nodec-simplify-unregister_memory_block_under_nodes.patch
drivers-base-memoryc-fixup-documentation-of-removable-phys_index-block_size_bytes.patch
driver-base-memoryc-validate-memory-block-size-early.patch
resource-use-pfn_up-pfn_down-in-walk_system_ram_range.patch
mm-memory_hotplug-handle-unaligned-start-and-nr_pages-in-online_pages_blocks.patch
mm-memory_hotplug-simplify-online_pages_range.patch
mm-memory_hotplug-online_pages-cannot-be-0-in-online_pages.patch
