From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756601AbdLVK5p (ORCPT ); Fri, 22 Dec 2017 05:57:45 -0500 Received: from mx1.redhat.com ([209.132.183.28]:48342 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753732AbdLVIs0 (ORCPT ); Fri, 22 Dec 2017 03:48:26 -0500 From: Baoquan He To: linux-kernel@vger.kernel.org Cc: Baoquan He , Ingo Molnar , Andrew Morton , Andy Lutomirski , Peter Zijlstra , Thomas Gleixner , Atsushi Kumagai , linux-mm@kvack.org Subject: [PATCH] mm/sparse.c: Wrong allocation for mem_section Date: Fri, 22 Dec 2017 16:48:18 +0800 Message-Id: <1513932498-20350-1-git-send-email-bhe@redhat.com> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Fri, 22 Dec 2017 08:48:26 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In commit 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. Signed-off-by: Baoquan He Tested-by: Dave Young Cc: Ingo Molnar Cc: Andrew Morton Cc: Andy Lutomirski Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Atsushi Kumagai Cc: linux-mm@kvack.org --- mm/sparse.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/sparse.c b/mm/sparse.c index 7a5dacaa06e3..2609aba121e8 100644 --- a/mm/sparse.c +++ b/mm/sparse.c @@ -211,7 +211,7 @@ void __init memory_present(int nid, unsigned long start, unsigned long end) 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); } -- 2.5.5