The patch titled
Subject: mm/memory_hotplug: drop PageReserved() check in online_pages_range()
has been added to the -mm tree. Its filename is
mm-memory_hotplug-drop-pagereserved-check-in-online_pages_range.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-memory_hotplug-drop-pagereserved-check-in-online_pages_range.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-memory_hotplug-drop-pagereserved-check-in-online_pages_range.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: David Hildenbrand <david@xxxxxxxxxx>
Subject: mm/memory_hotplug: drop PageReserved() check in online_pages_range()
move_pfn_range_to_zone() will set all pages to PG_reserved via
memmap_init_zone(). The only way a page could no longer be reserved would
be if a MEM_GOING_ONLINE notifier would clear PG_reserved - which is not
done (the online_page callback is used for that purpose by e.g., Hyper-V
instead). walk_system_ram_range() will never call online_pages_range()
with duplicate PFNs, so drop the PageReserved() check.
This seems to be a leftover from ancient times where the memmap was
initialized when adding memory and we wanted to check for already onlined
memory.
Link: http://lkml.kernel.org/r/20190814154109.3448-3-david@xxxxxxxxxx
Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
Acked-by: Michal Hocko <mhocko@xxxxxxxx>
Cc: Oscar Salvador <osalvador@xxxxxxx>
Cc: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx>
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: Arun KS <arunks@xxxxxxxxxxxxxx>
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, 1 insertion(+), 3 deletions(-)
--- a/mm/memory_hotplug.c~mm-memory_hotplug-drop-pagereserved-check-in-online_pages_range
+++ a/mm/memory_hotplug.c
@@ -653,9 +653,7 @@ static int online_pages_range(unsigned l
{
unsigned long onlined_pages = *(unsigned long *)arg;
- if (PageReserved(pfn_to_page(start_pfn)))
- onlined_pages += online_pages_blocks(start_pfn, nr_pages);
-
+ onlined_pages += online_pages_blocks(start_pfn, nr_pages);
online_mem_sections(start_pfn, start_pfn + nr_pages);
*(unsigned long *)arg = onlined_pages;
_
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
drivers-base-memoryc-dont-store-end_section_nr-in-memory-blocks.patch
resource-use-pfn_up-pfn_down-in-walk_system_ram_range.patch
mm-memory_hotplug-drop-pagereserved-check-in-online_pages_range.patch
mm-memory_hotplug-simplify-online_pages_range.patch
mm-memory_hotplug-make-sure-the-pfn-is-aligned-to-the-order-when-onlining.patch
mm-memory_hotplug-online_pages-cannot-be-0-in-online_pages.patch
