Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Liam Howlett <liam.howlett@oracle.com>
To:     Hugh Dickins <hughd@google.com>
CC:     Andrew Morton <akpm@linux-foundation.org>,
        Matthew Wilcox <willy@infradead.org>,
        Alexey Dobriyan <adobriyan@gmail.com>,
        Seth Jenkins <sethjenkins@google.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-mm@kvack.org" <linux-mm@kvack.org>
Subject: Re: [PATCH] mm: /proc/pid/smaps_rollup: fix maple tree search
Thread-Topic: [PATCH] mm: /proc/pid/smaps_rollup: fix maple tree search
Thread-Index: AQHY42mFCi5Khs8xZkmIrV77ByCJna4XaxeA
Date:   Thu, 20 Oct 2022 15:31:25 +0000
Message-ID: <20221020153101.425njbgquuu6ezv3@revolver>
References: <3011bee7-182-97a2-1083-d5f5b688e54b@google.com>
In-Reply-To: <3011bee7-182-97a2-1083-d5f5b688e54b@google.com>
Accept-Language: en-US
Content-Language: en-US
x-ms-exchange-antispam-messagedata-chunkcount: 1
x-ms-exchange-antispam-messagedata-0: =?us-ascii?Q?QPnsR4S3P45IU9dKJJ02GiP9SGrg59uCFAlFUiwXdZ7dCMLhN6pltcLoebds?=
 =?us-ascii?Q?eS8x+GCtoL2Wj1orAtKv6qM+CvOwVAK+j7I97cBnKenfyveTqC/+zN7pDl7C?=
 =?us-ascii?Q?C7ZTsLUZC3Ze3zBwiG/K5vndRE8zu7W39yj12mK3/A5TnIcUJUdxFe+OmRMR?=
 =?us-ascii?Q?shm9cBQ3cmCw9ZLqRQ6u2z4cQl6IOBIU/yVeX3pD90odrGai3p4ij3HgBgGT?=
 =?us-ascii?Q?/C9SgoKYRjQ0FplYduKinXuL8xWKVsd4iJfcorQ71zp9pwIfVHDbUEgPGJb1?=
 =?us-ascii?Q?1X/5+KAqpIDXVj151hrOXIEtGpC7GF/gTBFraX8m7OZLU65rNt9lDlNbS4nn?=
 =?us-ascii?Q?ODEslqb8wzkxq4a+49P4akU3GaYH0jO2l9bN3tiark81vjswJwo1vpiNEzrb?=
 =?us-ascii?Q?WOHrQwED785/PquUcB8WBYk1IOl+oC8HPuemqApcqU7ONA29dmXbQ342X0hg?=
 =?us-ascii?Q?zKdz/ZLi7R20jyaNmC/aCEdlSSZYNfdsGtISTbTy/tuEgkOhkBssegiU1IiF?=
 =?us-ascii?Q?zf8JJxRVYHBqa89/3/NBz2npIen+ZqZxUZvnG8fr0VVGkVy9eA2ioHySsBNR?=
 =?us-ascii?Q?r50AHSX1XzgXVTTbTyjTeR2oVPm5qC+VPfBOw30129ZRYsNLCJQOm5+hmi17?=
 =?us-ascii?Q?7vjd7xLyC8bTbQXPMe52+ftXD7tOZld4NvXCjKSE3lo/Y3m5Rv1oLtjACcF/?=
 =?us-ascii?Q?yqIa5ABLAtJdzlnD9jNhbfu9IOW9ytnKDRdcZLt4sK0Uxr38PZsHQFFPD8C+?=
 =?us-ascii?Q?pPae2xxwzODqlbWNOSaMV5lj+68cX72xQFsejq+5Jlk4Wy1UJXvYM7iEzME8?=
 =?us-ascii?Q?odltXs1bZXZtNtd0HFH06Y1fx6pnrOZxKT7yOlzs1NjfujDpi3I+Cem9YZU/?=
 =?us-ascii?Q?NjvqNfmsX2blyTH9YehC7FyK6haR0Y5uVTT6/Ze9R8JJaeLIrDdDPNPDfKYL?=
 =?us-ascii?Q?dCIMQawBZQ3Nz+yWkv1pNCKBhDkQGwqfygMG/y2PMihh1rWuQZgAsoJMrVtW?=
 =?us-ascii?Q?ieY3KA2jFFzKRYEf5PkS0X2OxuuqLJ2cMqV5C+BlF+R9n9yrxtFDZ9lHrKCF?=
 =?us-ascii?Q?w7Z35HKKhY12aGEsCEj9ybv3T/CV1B/3xPrhUbBxD94flW1ISFO4msTxK4lJ?=
 =?us-ascii?Q?MhBkl64+SagyMR2ayDXb7HmJMHc1hlyB+Kq1z8rH+Y9jeUtW6rgjGADtlQkP?=
 =?us-ascii?Q?NtMj5Y4z3vR+uBINuX9O9DZaKHgEAKV5gHtbjR+E0SSjJh7VHxbwE50Ff1s6?=
 =?us-ascii?Q?/qk4jXWN4g5gaVYcX8rcVm03Dqnn5joLFEewm3UB2/JiyPO61fPVqCfBRchu?=
 =?us-ascii?Q?ft//ZbMMDzaD2jBZwW0FZf2bUZ+227UtOCcW74jD9CxvlaY7qm/0Q31gjkH2?=
 =?us-ascii?Q?FuUAfFG3555rFa3fllJ/m8of2MluWXiGgw7lWVLcw04OrHG4aQQYlmNftriZ?=
 =?us-ascii?Q?5bRL7bWa8H4kPsIvwnrjs+lDDRxL25ZUYUF98RimMAfUyCxHN/pb5n44DIzd?=
 =?us-ascii?Q?zKXyDczogC5wiBiZT6+eMmOO5hSCM3Y3pm9akejnPX+QIUAuLGGpJZtnGbAa?=
 =?us-ascii?Q?9N00dE9VOAWGdbAtlkCdpGuwId7SaK67QKssRpzk99u/3CpXKJwbvLwVKNVX?=
 =?us-ascii?Q?CQ=3D=3D?=
Content-Type: text/plain; charset="us-ascii"
Content-ID: <E571B116599C3A4EB6BD1A2FB8DE3D3A@namprd10.prod.outlook.com>
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
X-OriginatorOrg: oracle.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-AuthSource: SN6PR10MB3022.namprd10.prod.outlook.com
X-MS-Exchange-CrossTenant-Network-Message-Id: b864b222-87ec-40ab-7519-08dab2b02633
X-MS-Exchange-CrossTenant-originalarrivaltime: 20 Oct 2022 15:31:25.0928
 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Hosted
X-MS-Exchange-CrossTenant-id: 4e2c6054-71cb-48f1-bd6c-3a9705aca71b
X-MS-Exchange-CrossTenant-mailboxtype: HOSTED
X-MS-Exchange-CrossTenant-userprincipalname: wkpUSQkbdR98Ea/+572nnTK7IlhIqyIJurMWcVYIJsOxf/v13i1ZhCsJwW09f+UnkbMYAVi0UrIK+UC2QTTCjA==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW5PR10MB5716
X-Proofpoint-Virus-Version: vendor=baseguard
 engine=ICAP:2.0.205,Aquarius:18.0.895,Hydra:6.0.545,FMLib:17.11.122.1
 definitions=2022-10-20_06,2022-10-20_01,2022-06-22_01
X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 malwarescore=0 spamscore=0 bulkscore=0
 mlxscore=0 phishscore=0 suspectscore=0 adultscore=0 mlxlogscore=894
 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2209130000
 definitions=main-2210200091
X-Proofpoint-ORIG-GUID: M-vMgeBLikabjTFQr6yoS85bXXiPH8qW
X-Proofpoint-GUID: M-vMgeBLikabjTFQr6yoS85bXXiPH8qW
X-Spam-Status: No, score=-2.8 required=5.0 tests=BAYES_00,DKIM_SIGNED,
        DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_LOW,
        RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_NONE autolearn=ham
        autolearn_force=no version=3.4.6
X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on
        lindbergh.monkeyblade.net
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org


Thanks Hugh.  I guess this 'optimisation' was a little more aggressive
and a little more buggy than needed.

Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>

* Hugh Dickins <hughd@google.com> [221018 23:18]:
> /proc/pid/smaps_rollup showed 0 kB for everything: now find first vma.
>=20
> Fixes: c4c84f06285e ("fs/proc/task_mmu: stop using linked list and highes=
t_vm_end")
> Signed-off-by: Hugh Dickins <hughd@google.com>
> ---
>=20
>  fs/proc/task_mmu.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>=20
> --- 6.1-rc1/fs/proc/task_mmu.c
> +++ linux/fs/proc/task_mmu.c
> @@ -902,7 +902,7 @@ static int show_smaps_rollup(struct seq_
>  		goto out_put_mm;
> =20
>  	hold_task_mempolicy(priv);
> -	vma =3D mas_find(&mas, 0);
> +	vma =3D mas_find(&mas, ULONG_MAX);
> =20
>  	if (unlikely(!vma))
>  		goto empty_set;=