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x-ms-exchange-messagesentrepresentingtype: 1 x-originating-ip: [142.167.216.168] x-ms-publictraffictype: Email x-ms-office365-filtering-correlation-id: a43b3676-6b61-4b08-c38d-08d72a509191 x-ms-office365-filtering-ht: Tenant x-microsoft-antispam: BCL:0;PCL:0;RULEID:(2390118)(7020095)(4652040)(8989299)(5600166)(711020)(4605104)(1401327)(4618075)(4534185)(4627221)(201703031133081)(201702281549075)(8990200)(2017052603328)(7193020);SRVR:VI1PR05MB6269; x-ms-traffictypediagnostic: VI1PR05MB6269: x-microsoft-antispam-prvs: x-ms-oob-tlc-oobclassifiers: OLM:7691; x-forefront-prvs: 01415BB535 x-forefront-antispam-report: SFV:NSPM;SFS:(10009020)(4636009)(39860400002)(396003)(136003)(376002)(346002)(366004)(189003)(199004)(386003)(54906003)(102836004)(66946007)(53546011)(6506007)(53936002)(6512007)(3846002)(52116002)(316002)(6116002)(66476007)(66556008)(64756008)(66446008)(71190400001)(256004)(14454004)(26005)(1076003)(66066001)(6436002)(36756003)(8676002)(25786009)(4326008)(305945005)(5660300002)(186003)(86362001)(7736002)(71200400001)(76176011)(33656002)(2906002)(6486002)(8936002)(6916009)(99286004)(486006)(476003)(478600001)(11346002)(2616005)(81156014)(229853002)(446003)(6246003)(81166006);DIR:OUT;SFP:1101;SCL:1;SRVR:VI1PR05MB6269;H:VI1PR05MB4141.eurprd05.prod.outlook.com;FPR:;SPF:None;LANG:en;PTR:InfoNoRecords;MX:1;A:1; received-spf: None (protection.outlook.com: mellanox.com does not designate permitted sender hosts) x-ms-exchange-senderadcheck: 1 x-microsoft-antispam-message-info: xJx5kMvdEmdL4l/EBzz1xBnKWwCJiReAExlcCqgUJAGowwln5DyiNlB1cL4Qw3vRobHskkqQz1rPpnBWJLYSEfe/pGWwQUE0lypDfu9JoCa+umkBfHKaZbXLd1cKn6UfEYj8bc6yQapdfXad+IEC4j7/xVVU8H1M7QRS8wE4SYaMWJl5KeZGbXmiO5XdXpdvHY7iwOB9IYeX624tc9lA8qLDolI5KM4g9sa9AM6B4Jq2Zcr1mREic8FDMdIAR/zKqa7WhbUaET99PLwgzv2BFrw589cwg+F58MteOtUa/5PqNl4f/CRJEFHmWVkutW64QtE0fSCC1AkTkdMj7Ut/VONhtOhbVoil+g2FzFm8UDkmNUD4PRceBTowaNkGM8mM+3doPWXNKnY0hNyVUnIN55b6NEzJcy5FlTVLYFoWpvY= x-ms-exchange-transport-forked: True Content-Type: text/plain; charset="iso-8859-1" Content-ID: <13598A34FD89014892271F429ACE899D@eurprd05.prod.outlook.com> Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: Mellanox.com X-MS-Exchange-CrossTenant-Network-Message-Id: a43b3676-6b61-4b08-c38d-08d72a509191 X-MS-Exchange-CrossTenant-originalarrivaltime: 26 Aug 2019 18:09:42.5922 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: a652971c-7d2e-4d9b-a6a4-d149256f461b X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: Ms67caVPI1xL6QIPQ45f408XuFjZVGN4eZ4NOTmxeOOExwJwjOf8QSMGJGkPmcWZxQk+IWGtouBhXrhcvjIaMA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: VI1PR05MB6269 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Aug 26, 2019 at 11:02:12AM -0700, Ralph Campbell wrote: >=20 > On 8/24/19 3:37 PM, Christoph Hellwig wrote: > > On Fri, Aug 23, 2019 at 03:17:52PM -0700, Ralph Campbell wrote: > > > Although hmm_range_fault() calls find_vma() to make sure that a vma e= xists > > > before calling walk_page_range(), hmm_vma_walk_hole() can still be ca= lled > > > with walk->vma =3D=3D NULL if the start and end address are not conta= ined > > > within the vma range. > >=20 > > Should we convert to walk_vma_range instead? Or keep walk_page_range > > but drop searching the vma ourselves? > >=20 > > Except for that the patch looks good to me: > >=20 > > Reviewed-by: Christoph Hellwig > >=20 >=20 > I think keeping the call to walk_page_range() makes sense. > Jason is hoping to be able to snapshot a range with & without vmas > and have the pfns[] filled with empty/valid entries as appropriate. >=20 > I plan to repost my patch changing hmm_range_fault() to use > walk.test_walk which will remove the call to find_vma(). > Jason had some concerns about testing it so that's why I have > been working on some HMM self tests before resending it. I'm really excited to see tests for hmm_range_fault()! Did you find this bug with the tests?? Jason