From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pb0-f54.google.com (mail-pb0-f54.google.com [209.85.160.54]) by kanga.kvack.org (Postfix) with ESMTP id 9F8506B0039 for ; Thu, 14 Nov 2013 18:34:03 -0500 (EST) Received: by mail-pb0-f54.google.com with SMTP id ro12so2730415pbb.13 for ; Thu, 14 Nov 2013 15:34:03 -0800 (PST) Received: from psmtp.com ([74.125.245.186]) by mx.google.com with SMTP id yd9si101251pab.234.2013.11.14.15.34.00 for ; Thu, 14 Nov 2013 15:34:02 -0800 (PST) Subject: [PATCH 1/2] mm: hugetlbfs: Add some VM_BUG_ON()s to catch non-hugetlbfs pages From: Dave Hansen Date: Thu, 14 Nov 2013 15:33:58 -0800 References: <20131114233357.90EE35C1@viggo.jf.intel.com> In-Reply-To: <20131114233357.90EE35C1@viggo.jf.intel.com> Message-Id: <20131114233358.2B10EA33@viggo.jf.intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, dave.jiang@intel.com, Mel Gorman , akpm@linux-foundation.org, dhillf@gmail.com, Naoya Horiguchi , Dave Hansen From: Dave Hansen 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 some VM_BUG_ON()s for the next hapless VM developer that tries the same thing. Signed-off-by: Dave Hansen Reviewed-by: Naoya Horiguchi --- linux.git-davehans/include/linux/hugetlb.h | 1 + linux.git-davehans/mm/hugetlb.c | 1 + 2 files changed, 2 insertions(+) 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 2013-11-14 15:09:38.707180957 -0800 +++ linux.git-davehans/include/linux/hugetlb.h 2013-11-14 15:09:38.710181090 -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)); } diff -puN mm/hugetlb.c~bug-not-hugetlbfs-in-copy_huge_page mm/hugetlb.c --- linux.git/mm/hugetlb.c~bug-not-hugetlbfs-in-copy_huge_page 2013-11-14 15:09:38.708181001 -0800 +++ linux.git-davehans/mm/hugetlb.c 2013-11-14 15:09:38.711181135 -0800 @@ -498,6 +498,7 @@ void copy_huge_page(struct page *dst, st int i; struct hstate *h = page_hstate(src); + VM_BUG_ON(!h); if (unlikely(pages_per_huge_page(h) > MAX_ORDER_NR_PAGES)) { copy_gigantic_page(dst, src); return; _ -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org