From: Baoquan He bhe@redhat.com 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@redhat.com Fixes: 83e3c48729 ("mm/sparsemem: Allocate mem_section at runtime for CONFIG_SPARSEMEM_EXTREME=y") Signed-off-by: Baoquan He bhe@redhat.com Tested-by: Dave Young dyoung@redhat.com Acked-by: Kirill A. Shutemov kirill.shutemov@linux.intel.com Cc: Kirill A. Shutemov kirill.shutemov@linux.intel.com Cc: Ingo Molnar mingo@kernel.org Cc: Andy Lutomirski luto@amacapital.net Cc: Peter Zijlstra peterz@infradead.org Cc: Thomas Gleixner tglx@linutronix.de Cc: Atsushi Kumagai ats-kumagai@wm.jp.nec.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

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); } _