From: Baoquan He <bhe@xxxxxxxxxx>
Subject: mm/sparse.c: wrong allocation for mem_section
In 83e3c48729 ("mm/sparsemem: Allocate mem_section at runtime for CONFIG_SPARSEMEM_EXTREME=y") mem_section is allocated at runtime to save memory. While it allocates
the first dimension of array with sizeof(struct mem_section). It costs
extra memory, should be sizeof(struct mem_section*).
Fix it.
Link: http://lkml.kernel.org/r/1513932498-20350-1-git-send-email-bhe@xxxxxxxxxx
Fixes: 83e3c48729 ("mm/sparsemem: Allocate mem_section at runtime for CONFIG_SPARSEMEM_EXTREME=y")
Signed-off-by: Baoquan He <bhe@xxxxxxxxxx>
Tested-by: Dave Young <dyoung@xxxxxxxxxx>
Acked-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Atsushi Kumagai <ats-kumagai@xxxxxxxxxxxxx>
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-sparsec-wrong-allocation-for-mem_section mm/sparse.c
--- a/mm/sparse.c~mm-sparsec-wrong-allocation-for-mem_section
+++ a/mm/sparse.c
@@ -211,7 +211,7 @@ void __init memory_present(int nid, unsi
if (unlikely(!mem_section)) {
unsigned long size, align;
- size = sizeof(struct mem_section) * NR_SECTION_ROOTS;
+ size = sizeof(struct mem_section*) * NR_SECTION_ROOTS;
align = 1 << (INTERNODE_CACHE_SHIFT);
mem_section = memblock_virt_alloc(size, align);
}
_