The patch titled
Subject: mm: sections are not offlined during memory hotremove
has been added to the -mm tree. Its filename is
mm-sections-are-not-offlined-during-memory-hotremove.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-sections-are-not-offlined-during-memory-hotremove.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-sections-are-not-offlined-during-memory-hotremove.patch
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------------------------------------------------------
From: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx>
Subject: mm: sections are not offlined during memory hotremove
Memory hotplug and hotremove operate with per-block granularity. If the
machine has a large amount of memory (more than 64G), the size of a memory
block can span multiple sections. By mistake, during hotremove we set
only the first section to offline state.
The bug was discovered because kernel selftest started to fail:
https://lkml.kernel.org/r/20180423011247.GK5563@yexl-desktop
After commit, "mm/memory_hotplug: optimize probe routine". But, the bug
is older than this commit. In this optimization we also added a check for
sections to be in a proper state during hotplug operation.
Link: http://lkml.kernel.org/r/20180427145257.15222-1-pasha.tatashin@xxxxxxxxxx
Fixes: 2d070eab2e82 ("mm: consider zone which is not fully populated to have holes")
Signed-off-by: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx>
Acked-by: Michal Hocko <mhocko@xxxxxxxx>
Reviewed-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Steven Sistare <steven.sistare@xxxxxxxxxx>
Cc: Daniel Jordan <daniel.m.jordan@xxxxxxxxxx>
Cc: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/sparse.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff -puN mm/sparse.c~mm-sections-are-not-offlined-during-memory-hotremove mm/sparse.c
--- a/mm/sparse.c~mm-sections-are-not-offlined-during-memory-hotremove
+++ a/mm/sparse.c
@@ -629,7 +629,7 @@ void offline_mem_sections(unsigned long
unsigned long pfn;
for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
- unsigned long section_nr = pfn_to_section_nr(start_pfn);
+ unsigned long section_nr = pfn_to_section_nr(pfn);
struct mem_section *ms;
/*
_
Patches currently in -mm which might be from pasha.tatashin@xxxxxxxxxx are
mm-sections-are-not-offlined-during-memory-hotremove.patch
sparc64-ng4-memset-32-bits-overflow.patch
