From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933682AbcAYQyr (ORCPT ); Mon, 25 Jan 2016 11:54:47 -0500 Received: from prv-mh.provo.novell.com ([137.65.248.74]:46959 "EHLO prv-mh.provo.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932767AbcAYQyl convert rfc822-to-8bit (ORCPT ); Mon, 25 Jan 2016 11:54:41 -0500 Message-Id: <56A6615E02000078000CAC96@prv-mh.provo.novell.com> X-Mailer: Novell GroupWise Internet Agent 14.2.0 Date: Mon, 25 Jan 2016 09:54:38 -0700 From: "Jan Beulich" To: , , Cc: Subject: [PATCH] x86/mm: avoid premature success when changing page attributes Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8BIT Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Since successful return from __cpa_process_fault() makes __change_page_attr() exit early (and successfully), its caller needs to be instructed to continue its iteration by adjusting ->numpages. While this already happens on one of __cpa_process_fault()'s successful exit paths, the other needs this done similarly. This was in particular a problem when the top level caller passed zero for "checkalias" (becoming the "primary" value for the other two mentioned functions), as is the case in change_page_attr_set_clr() when the OR of "mask_set" and "mask_clr" equals _PAGE_NX, as e.g. passed from set_memory_{,n}x(). Signed-off-by: Jan Beulich --- arch/x86/mm/pageattr.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- 4.5-rc1/arch/x86/mm/pageattr.c +++ 4.5-rc1-x86-cpa-non-primary/arch/x86/mm/pageattr.c @@ -1122,8 +1122,10 @@ static int __cpa_process_fault(struct cp /* * Ignore all non primary paths. */ - if (!primary) + if (!primary) { + cpa->numpages = 1; return 0; + } /* * Ignore the NULL PTE for kernel identity mapping, as it is expected