From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757081AbYKQHZ5 (ORCPT ); Mon, 17 Nov 2008 02:25:57 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753859AbYKQHVL (ORCPT ); Mon, 17 Nov 2008 02:21:11 -0500 Received: from kroah.org ([198.145.64.141]:38298 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752683AbYKQHVA (ORCPT ); Mon, 17 Nov 2008 02:21:00 -0500 Date: Sun, 16 Nov 2008 23:15:03 -0800 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: Justin Forbes , Zwane Mwaikambo , "Theodore Ts'o" , Randy Dunlap , Dave Jones , Chuck Wolber , Chris Wedgwood , Michael Krufky , Chuck Ebbert , Domenico Andreoli , Willy Tarreau , Rodrigo Rubira Branco , Jake Edge , Eugene Teo , torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Adam Litke , Jon Tollefson , Mel Gorman , Greg Kroah-Hartman Subject: [patch 13/46] hugetlb: make unmap_ref_private multi-size-aware Message-ID: <20081117071503.GN29522@kroah.com> References: <20081117070621.430169021@blue.kroah.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline; filename="hugetlb-make-unmap_ref_private-multi-size-aware.patch" In-Reply-To: <20081117071333.GA29522@kroah.com> User-Agent: Mutt/1.5.16 (2007-06-09) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.27-stable review patch. If anyone has any objections, please let us know. ------------------ From: Adam Litke commit 7526674de0c921e7f1e9b6f71a1f9d832557b554 upstream. Oops. Part of the hugetlb private reservation code was not fully converted to use hstates. When a huge page must be unmapped from VMAs due to a failed COW, HPAGE_SIZE is used in the call to unmap_hugepage_range() regardless of the page size being used. This works if the VMA is using the default huge page size. Otherwise we might unmap too much, too little, or trigger a BUG_ON. Rare but serious -- fix it. Signed-off-by: Adam Litke Cc: Jon Tollefson Cc: Mel Gorman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- mm/hugetlb.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1797,6 +1797,7 @@ int unmap_ref_private(struct mm_struct * struct page *page, unsigned long address) { + struct hstate *h = hstate_vma(vma); struct vm_area_struct *iter_vma; struct address_space *mapping; struct prio_tree_iter iter; @@ -1806,7 +1807,7 @@ int unmap_ref_private(struct mm_struct * * vm_pgoff is in PAGE_SIZE units, hence the different calculation * from page cache lookup which is in HPAGE_SIZE units. */ - address = address & huge_page_mask(hstate_vma(vma)); + address = address & huge_page_mask(h); pgoff = ((address - vma->vm_start) >> PAGE_SHIFT) + (vma->vm_pgoff >> PAGE_SHIFT); mapping = (struct address_space *)page_private(page); @@ -1825,7 +1826,7 @@ int unmap_ref_private(struct mm_struct * */ if (!is_vma_resv_set(iter_vma, HPAGE_RESV_OWNER)) unmap_hugepage_range(iter_vma, - address, address + HPAGE_SIZE, + address, address + huge_page_size(h), page); } --