From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752596AbdKFJOX (ORCPT ); Mon, 6 Nov 2017 04:14:23 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:56376 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752177AbdKFJOU (ORCPT ); Mon, 6 Nov 2017 04:14:20 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mike Kravetz , Naoya Horiguchi , Michal Hocko , Aneesh Kumar , Anshuman Khandual , Andrew Morton , Linus Torvalds Subject: [PATCH 4.13 21/36] fs/hugetlbfs/inode.c: fix hwpoison reserve accounting Date: Mon, 6 Nov 2017 10:12:34 +0100 Message-Id: <20171106085048.000191993@linuxfoundation.org> X-Mailer: git-send-email 2.15.0 In-Reply-To: <20171106085047.005824077@linuxfoundation.org> References: <20171106085047.005824077@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.13-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mike Kravetz commit ab615a5b879292e83653be60aa82113f7c6f462d upstream. Calling madvise(MADV_HWPOISON) on a hugetlbfs page will result in bad (negative) reserved huge page counts. This may not happen immediately, but may happen later when the underlying file is removed or filesystem unmounted. For example: AnonHugePages: 0 kB ShmemHugePages: 0 kB HugePages_Total: 1 HugePages_Free: 0 HugePages_Rsvd: 18446744073709551615 HugePages_Surp: 0 Hugepagesize: 2048 kB In routine hugetlbfs_error_remove_page(), hugetlb_fix_reserve_counts is called after remove_huge_page. hugetlb_fix_reserve_counts is designed to only be called/used only if a failure is returned from hugetlb_unreserve_pages. Therefore, call hugetlb_unreserve_pages as required and only call hugetlb_fix_reserve_counts in the unlikely event that hugetlb_unreserve_pages returns an error. Link: http://lkml.kernel.org/r/20171019230007.17043-2-mike.kravetz@oracle.com Fixes: 78bb920344b8 ("mm: hwpoison: dissolve in-use hugepage in unrecoverable memory error") Signed-off-by: Mike Kravetz Acked-by: Naoya Horiguchi Cc: Michal Hocko Cc: Aneesh Kumar Cc: Anshuman Khandual Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- fs/hugetlbfs/inode.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) --- a/fs/hugetlbfs/inode.c +++ b/fs/hugetlbfs/inode.c @@ -855,9 +855,12 @@ static int hugetlbfs_error_remove_page(s struct page *page) { struct inode *inode = mapping->host; + pgoff_t index = page->index; remove_huge_page(page); - hugetlb_fix_reserve_counts(inode); + if (unlikely(hugetlb_unreserve_pages(inode, index, index + 1, 1))) + hugetlb_fix_reserve_counts(inode); + return 0; }