[PATCH 4.14 10/38] mm/sparse.c: wrong allocation for mem_section

[Greg Kroah-Hartman]

4.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Baoquan He <bhe@xxxxxxxxxx>

commit d09cfbbfa0f761a97687828b5afb27b56cbf2e19 upstream.

In commit 83e3c48729d9 ("mm/sparsemem: Allocate mem_section at runtime
for CONFIG_SPARSEMEM_EXTREME=y") mem_section is allocated at runtime to
save memory.

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>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 mm/sparse.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/mm/sparse.c
+++ b/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);
 	}