From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753123Ab3KOW4M (ORCPT ); Fri, 15 Nov 2013 17:56:12 -0500 Received: from mga01.intel.com ([192.55.52.88]:29147 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752682Ab3KOWz5 (ORCPT ); Fri, 15 Nov 2013 17:55:57 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.93,710,1378882800"; d="scan'208";a="434314945" Subject: [v3][PATCH 1/2] mm: hugetlbfs: Add VM_BUG_ON()s to catch non-hugetlbfs pages To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, dave.jiang@intel.com, akpm@linux-foundation.org, dhillf@gmail.com, Naoya Horiguchi , Mel Gorman , Dave Hansen From: Dave Hansen Date: Fri, 15 Nov 2013 14:55:52 -0800 References: <20131115225550.737E5C33@viggo.jf.intel.com> In-Reply-To: <20131115225550.737E5C33@viggo.jf.intel.com> Message-Id: <20131115225552.6DCE2E1B@viggo.jf.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dave Hansen Changes from v2: * Removed the VM_BUG_ON() from copy_huge_page() since the next patch makes it able to handle non-hugetlbfs pages -- Dave Jiang reported that he was seeing oopses when running NUMA systems and default_hugepagesz=1G. I traced the issue down to migrate_page_copy() trying to use the same code for hugetlb pages and transparent hugepages. It should not have been trying to pass thp pages in there. So, add a VM_BUG_ON()s for the next hapless developer that tries to use page_hstate() on a non-hugetlbfs page. Signed-off-by: Dave Hansen Reviewed-by: Naoya Horiguchi Acked-by: Mel Gorman --- linux.git-davehans/include/linux/hugetlb.h | 1 + 1 file changed, 1 insertion(+) diff -puN include/linux/hugetlb.h~bug-not-hugetlbfs-in-copy_huge_page include/linux/hugetlb.h --- linux.git/include/linux/hugetlb.h~bug-not-hugetlbfs-in-copy_huge_page 2013-11-15 14:44:41.550357120 -0800 +++ linux.git-davehans/include/linux/hugetlb.h 2013-11-15 14:44:41.553357255 -0800 @@ -355,6 +355,7 @@ static inline pte_t arch_make_huge_pte(p static inline struct hstate *page_hstate(struct page *page) { + VM_BUG_ON(!PageHuge(page)); return size_to_hstate(PAGE_SIZE << compound_order(page)); } _