From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753025AbdLGQTg (ORCPT ); Thu, 7 Dec 2017 11:19:36 -0500 Received: from omzsmtpe01.verizonbusiness.com ([199.249.25.210]:51273 "EHLO omzsmtpe01.verizonbusiness.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932924AbdLGP4y (ORCPT ); Thu, 7 Dec 2017 10:56:54 -0500 From: alexander.levin@verizon.com Cc: Jan Kara , Dan Williams , alexander.levin@verizon.com X-Host: mariner.tdc.vzwcorp.com To: "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" Subject: [PATCH AUTOSEL for 3.18 42/59] mm: Handle 0 flags in _calc_vm_trans() macro Thread-Topic: [PATCH AUTOSEL for 3.18 42/59] mm: Handle 0 flags in _calc_vm_trans() macro Thread-Index: AQHTb3NBNO6BcBVwrkeyopwOe5k/Hw== Date: Thu, 7 Dec 2017 15:51:33 +0000 Message-ID: <20171207155116.6013-42-alexander.levin@verizon.com> References: <20171207155116.6013-1-alexander.levin@verizon.com> In-Reply-To: <20171207155116.6013-1-alexander.levin@verizon.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-messagesentrepresentingtype: 1 x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.144.60.250] Content-Type: text/plain; charset="iso-8859-1" MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by nfs id vB7GJfWp004806 From: Jan Kara [ Upstream commit 592e254502041f953e84d091eae2c68cba04c10b ] _calc_vm_trans() does not handle the situation when some of the passed flags are 0 (which can happen if these VM flags do not make sense for the architecture). Improve the _calc_vm_trans() macro to return 0 in such situation. Since all passed flags are constant, this does not add any runtime overhead. Signed-off-by: Jan Kara Signed-off-by: Dan Williams Signed-off-by: Sasha Levin --- include/linux/mman.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/include/linux/mman.h b/include/linux/mman.h index 16373c8f5f57..369bc3405a6d 100644 --- a/include/linux/mman.h +++ b/include/linux/mman.h @@ -63,8 +63,9 @@ static inline int arch_validate_prot(unsigned long prot) * ("bit1" and "bit2" must be single bits) */ #define _calc_vm_trans(x, bit1, bit2) \ + ((!(bit1) || !(bit2)) ? 0 : \ ((bit1) <= (bit2) ? ((x) & (bit1)) * ((bit2) / (bit1)) \ - : ((x) & (bit1)) / ((bit1) / (bit2))) + : ((x) & (bit1)) / ((bit1) / (bit2)))) /* * Combine the mmap "prot" argument into "vm_flags" used internally. -- 2.11.0