From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mel Gorman Message-Id: <20080710173041.16433.21192.sendpatchset@skynet.skynet.ie> In-Reply-To: <20080710173001.16433.87538.sendpatchset@skynet.skynet.ie> References: <20080710173001.16433.87538.sendpatchset@skynet.skynet.ie> Subject: [PATCH 2/2] [PATCH] Align faulting address to a hugepage boundary before unmapping Date: Thu, 10 Jul 2008 18:30:41 +0100 (IST) Sender: owner-linux-mm@kvack.org Return-Path: To: akpm@linux-foundation.org Cc: apw@shadowen.org, linux-mm@kvack.org, agl@us.ibm.com, linux-kernel@vger.kernel.org, Mel Gorman List-ID: When taking a fault for COW on a private mapping it is possible that the parent will have to steal the original page from its children due to an insufficient hugepage pool. In this case, unmap_ref_private() is called for the faulting address to unmap via unmap_hugepage_range(). This patch ensures that the address used for unmapping is hugepage-aligned. Signed-off-by: Mel Gorman --- mm/hugetlb.c | 1 + 1 file changed, 1 insertion(+) diff -rup -X /usr/src/patchset-0.6/bin//dontdiff linux-2.6.26-rc8-mm1-clean/mm/hugetlb.c linux-2.6.26-rc8-mm1-fix-needsreserve-check/mm/hugetlb.c --- linux-2.6.26-rc8-mm1-clean/mm/hugetlb.c 2008-07-08 11:54:34.000000000 -0700 +++ linux-2.6.26-rc8-mm1-fix-needsreserve-check/mm/hugetlb.c 2008-07-08 15:50:00.000000000 -0700 @@ -1767,6 +1767,7 @@ 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)); pgoff = ((address - vma->vm_start) >> PAGE_SHIFT) + (vma->vm_pgoff >> PAGE_SHIFT); mapping = (struct address_space *)page_private(page); -- 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