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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?V3u6NRQbfsGiXfxGnOp848irCu7pn3FUEJ6D+GFM/ATsym+d8kqtc8U5wmZ2?= =?us-ascii?Q?a6HelEoT+HWwbBSq+hyUsmgqXBWcjqusrotNc88BnMqJeOm8gLxz2ku20XxC?= =?us-ascii?Q?3KoTTf4thbA0h+qymYVBnTt5rSepDW/1f+4JbM/ck1qnSFJlEEg82hjjhd2D?= =?us-ascii?Q?ye8RhfdlEh5VaPdwq5SeZVqH+jGli3D/iL9wWEI6XZVlwnU60QJYX2W0I8s7?= =?us-ascii?Q?vLJTda/aM/6azSmyo3Eu+FKB93JfEqqr/UV4/A/hVRNLZWpFzHstJUcGDaVb?= =?us-ascii?Q?UMtypNMKZdg/TNjpag/FGrupDR1hWhk9vxo13REMSb/D1/uRxyeeN1/DxdIO?= =?us-ascii?Q?XDdSHbfvzMgBShN7rcopB6zQR5rjowa6q7SSudPPjB2U0tacVAyiz75hZ46O?= =?us-ascii?Q?KmaAbQMDBBFiqRpapZoy45tOWhGaETz1W2KaQc+tGlnM6K+42zm4w4A2TWRz?= =?us-ascii?Q?nXqwoIcSN2ifOiP2J8Or3qvKkZq6L04ZDrkInLbkV+hitoqI7Rdw50pD0xfJ?= =?us-ascii?Q?Jnu2kjVB9+mKtMU8+fk/j+X9DJGllVFnGaNdJwRIYRNTGUcpazUij2LyI3Pa?= =?us-ascii?Q?P8NUvD+90+s5SzjOc9Pb1LWa0s8aY9E35J3QIxONo0RD1qvQO2WUlXBcdDrU?= =?us-ascii?Q?jONzSfR3fVZolJDMsw9fXkkdCiW1mew/eW+UhQo7QSWsJU3WhdU85AUImDkA?= =?us-ascii?Q?dhA82Eym5xzAohgd8wuCIv2sFL917DuwKQF7Xpj1Nj0H4PytMyWAgvZeNoWz?= =?us-ascii?Q?/QFtGTq6JAl1him23g0Mwdy0Sp7GVqHvVEGJ8BBu2S2/sYrvN4lETRSSRxEq?= =?us-ascii?Q?d67+xfMhgwMZu9oz7M+13FWKcfiQbXtoEwE3ApbpM3qBAMvnZMxvfRqks2uC?= =?us-ascii?Q?nMAHkd1BLmEmsOBzSNJit3kV2PytkCJNm2z5Mreu/symJRVpnyuPjZfICXtt?= =?us-ascii?Q?iQcuaU2gT5ySnA8FvIyjfpTxlLGGbQRidDzA9cvIPLZoCPm6om3iqY9eajm+?= =?us-ascii?Q?dDaupkLqHgYRnfVGcAWBLiptMusUL2Ah8iqEX/tdVYGYowyr8XgKQdFdELla?= =?us-ascii?Q?x30kwNXO9/5QjkVbFPX50J28qP7vEQ1vpp7ZT7SIylAN2B5FhcgMg0xnLBg8?= =?us-ascii?Q?KtieO5x6BLPNukTU5jCU3OyWXYrMV8BKh5nmzXCEsu8Qpj8nhFGkRaoedUgg?= =?us-ascii?Q?Ah8QY1y09lm4n/LyQPCjCAsK+Qf/ZsWDJgn6yosbS8pj0bodtWj9OwZ/mMsE?= =?us-ascii?Q?TCLGyJRtYvDkVJzgxnhR+a0DO3RxuA4BuSA1VVbWSHjI39s/ol8+I8NbsVFf?= =?us-ascii?Q?SksqnichuzBBWe9mh5SbaVkQ7FFohZ8iQbtFPqYqpkM1fcwdPmL29g7VA4dA?= =?us-ascii?Q?6CI7Epn1X6b3TVYC1/QbFDVkiGJbYasPhv5ZwBLGj76fkvT2es7wGJbVvRCG?= =?us-ascii?Q?F6JsW77rRnzlhnPJnkTn9AP3svZEdE1skRpbB7E2zjYrXyXiBGetBLxPF/QM?= =?us-ascii?Q?RU1L/ZgOJLtuAGP7Mki6G9oqEZm9BaM1RqJg9krEeKC52HG/lofVtXzfBab3?= =?us-ascii?Q?YKUtxrSDl3lHwfQs3YKGbisEuCWVPRA+ydKJlocQ?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: db4e7582-ba79-46e1-97ce-08dc64c3bed1 X-MS-Exchange-CrossTenant-AuthSource: DS7PR12MB5744.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 25 Apr 2024 01:05:06.3450 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: tQDKPsAp3plAlnEuoaof6sqYl6Q+W08YqNnKiH+51V/rLK2C7X4Vg6L+89rszHne X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA1PR12MB7198 --=_MailMate_93DFCBEB-B9E7-4EDC-8EDC-CFB367B75CC1_= Content-Type: text/plain Content-Transfer-Encoding: quoted-printable On 24 Apr 2024, at 18:54, Luis Chamberlain wrote: > Don't allow to query beyond a mapped file's length. Since this is just > a debugfs interface allow userspace to be lazy and use a large value so= > we can just use the entire file. > > Without this we can end up wasting cycles looking for folios which > just don't exist for no good reason. > > Signed-off-by: Luis Chamberlain > --- > mm/huge_memory.c | 9 ++++++--- > 1 file changed, 6 insertions(+), 3 deletions(-) > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > index 8386d24a163e..86a8c7b3b8dc 100644 > --- a/mm/huge_memory.c > +++ b/mm/huge_memory.c > @@ -3535,7 +3535,7 @@ static int split_huge_pages_in_file(const char *f= ile_path, pgoff_t off_start, > struct file *candidate; > struct address_space *mapping; > int ret =3D -EINVAL; > - pgoff_t index; > + pgoff_t index, fsize; > int nr_pages =3D 1; > unsigned long total =3D 0, split =3D 0; > > @@ -3547,11 +3547,14 @@ static int split_huge_pages_in_file(const char = *file_path, pgoff_t off_start, > if (IS_ERR(candidate)) > goto out; > > + mapping =3D candidate->f_mapping; > + fsize =3D i_size_read(mapping->host); > + if (off_end > fsize) > + off_end =3D fsize; > + > pr_debug("split file-backed THPs in file: %s, page offset: [0x%lx - 0= x%lx]\n", > file_path, off_start, off_end); > > - mapping =3D candidate->f_mapping; > - > for (index =3D off_start; index < off_end; index +=3D nr_pages) { > struct folio *folio =3D filemap_get_folio(mapping, index); LGTM. Reviewed-by: Zi Yan -- Best Regards, Yan, Zi --=_MailMate_93DFCBEB-B9E7-4EDC-8EDC-CFB367B75CC1_= Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename=signature.asc Content-Type: application/pgp-signature; name=signature.asc -----BEGIN PGP SIGNATURE----- iQJDBAEBCgAtFiEE6rR4j8RuQ2XmaZol4n+egRQHKFQFAmYprEAPHHppeUBudmlk aWEuY29tAAoJEOJ/noEUByhUoa0QAJFvYFTTzizyPC8tlq87XYVxqPXn+BTz6K1B m86NEIR3LxM59xEwGbmT/ReMR628Qs4nj9S86v5WGN09NaPyArNQcOoW9PR9NZD0 II/ldsGg7U7xrev80vfyRIQ+VUZutz8Oaoe41OfmGAMrp/5S2Kpz73knf2Zxd7KN M71TQlzwJntdx+XK+alQnJj4UcgyMq3HMvA6Yr2lmgQ85Et7LWrCgo5W3oovz+n5 kB57Y2JFZyZkaDKZKJIM4M7LYSuvJYxrjMVLQZi5pETSgfYYZwlul2br+KXrlAAP suV+K+VyWsTZ0rgQCHHZx1v4DLH2EBbkqQKLOfyPu/+m7PuxsKCAhTvh4PAMSz3h UvpcYLYVPWh0dsDHPhhGp7+cABwahwAsT6HC5/MfnZepBbvrHRIs+MJIpO1fv+mi qF7p7MBfwyKXSueS7MnYfEFqiQBoZNoh0PfJ7Hvw54YrzSy5uqgPr7PpZorw/mkX fj0+dgyQOJZ63FAb9pq+veqT2kCqAp9IGMnPsnZ3UWx9M0l+XlRSljhZ1IEYt+UB 2aC4kkWhyBFxQ3Y2XmUXR5quI2uifBeX8jLxOwuOUf1yNEIsXVLKvUPaWrDI4dH7 r4H3/o1r+bgLhU0ZRjqdYvAy7CpauZcQNL0Z2Rt/FArZ1ph/QKB8JfgHaLKDhY7B 8WPHmg6D =CPe/ -----END PGP SIGNATURE----- --=_MailMate_93DFCBEB-B9E7-4EDC-8EDC-CFB367B75CC1_=--