From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx187.postini.com [74.125.245.187]) by kanga.kvack.org (Postfix) with SMTP id DFBB76B0007 for ; Thu, 31 Jan 2013 10:26:14 -0500 (EST) From: Naoya Horiguchi Subject: [PATCH] HWPOISON: fix wrong num_poisoned_pages in handling memory error on thp Date: Thu, 31 Jan 2013 10:25:58 -0500 Message-Id: <1359645958-9127-1-git-send-email-n-horiguchi@ah.jp.nec.com> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton , Andi Kleen , Tony Luck Cc: Wu Fengguang , linux-mm@kvack.org, linux-kernel@vger.kernel.org num_poisoned_pages counts up the number of pages isolated by memory errors. But for thp, only one subpage is isolated because memory error handler splits it, so it's wrong to add (1 << compound_trans_order). Signed-off-by: Naoya Horiguchi --- mm/memory-failure.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git mmotm-2013-01-23-17-04.orig/mm/memory-failure.c mmotm-2013-01-23-17-04/mm/memory-failure.c index 9cab165..d5c50d6 100644 --- mmotm-2013-01-23-17-04.orig/mm/memory-failure.c +++ mmotm-2013-01-23-17-04/mm/memory-failure.c @@ -1039,7 +1039,14 @@ int memory_failure(unsigned long pfn, int trapno, int flags) return 0; } - nr_pages = 1 << compound_trans_order(hpage); + /* + * If a thp is hit by a memory failure, it's supposed to be split. + * So we should add only one to num_poisoned_pages for that case. + */ + if (PageHuge(p)) + nr_pages = 1 << compound_trans_order(hpage); + else /* normal page or thp */ + nr_pages = 1; atomic_long_add(nr_pages, &num_poisoned_pages); /* -- 1.7.11.7 -- 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