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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?8eX8rNuiKtXZFs+1nFf8HF9bb2DS+CArbfs1c+EAHyu9Lm4CwH159zUrElZa?= =?us-ascii?Q?CQDL9jVygKAHAll6g2RootJ1N8486iX1w1vCacvJdPGfIjhEjggmGfti4FFa?= =?us-ascii?Q?0vammPKJqdPo//231Yz+wLuMD0qMFdCFr79OApWVKdhKFDvd6CpCf5pgoA1L?= =?us-ascii?Q?3RTjz/F3ZQIUqQijOJWZiBhqzJoGUioncZ6K5RqbTSR09zxz9+Yn/M0dRSBg?= =?us-ascii?Q?z2XMlsdKu/RaWwWLAfx2Po+WEKZ+GEKk7RlAkMqUjse60zpW/aSwVppxugMt?= =?us-ascii?Q?OfZS+M7/8aI36FaRX6GS4fp2nGnYBgM6e34STL7h7hmLJFw3xjtnk4wPSNVX?= =?us-ascii?Q?KTYI1h17V1kMRq0u8CDamDru35Gtp0uSab4rCXZ+k5ruM2ByQMOAKKFNGnbi?= =?us-ascii?Q?pBxe7HzscQUzG01qP5bUFabU6sLukQ5Jomr5M5W11jY+WQmf1kpl2NREgNsy?= =?us-ascii?Q?G5WJsY4DQdwNkVmib0ykMVFnma/iPMZu61IZ09WCNWFfzgAz0Zn8aZkA854/?= =?us-ascii?Q?dWfa5ZrvxVGY+MRzm9zClhDvNY/CKdgtOfcTsS0sGKS5Q+lq4prCNHuNfjut?= =?us-ascii?Q?gi2rZ09OxNAb9J9xi68KOUj+GusHmWLITJzRHa7o+NfcbX8sjEDKbJfLrzDg?= =?us-ascii?Q?fT3F8VrhBoI6wpaaCJZgyreCKBSaHBgOYXmXMTxjmVrTyoshzKyrtszxqH4z?= =?us-ascii?Q?z1z/zK/wN0zi6D2EDSsjh75Ci/GcbI3kHk7XkmY+a+Yy+eAWsWAbPsTPTIWx?= =?us-ascii?Q?7Is25uSvtP/tEaWYoH78hT2xgYRLWnnxHFSKuF2H32UnduugeQWf5LpNwIvm?= =?us-ascii?Q?GImBcVQoDS8W8NV25lKQhKIiBNLmyqOtr07VFdaGtLvJUepCpCMmb/1XGgs/?= =?us-ascii?Q?fNxVN+paa8my/PW2JkWHb20R9YB7/OBbsDzkl70iPq7l/sJN8PZHovAWTPfB?= =?us-ascii?Q?FPMjs6g8H2iJZ3JPQPvZLR71Fk8h72yE6tyxkv1KbYztSzvvS/nmd526Qdjk?= =?us-ascii?Q?Xi9bvuczcc8iUGDLJLKdGDwKpH3BdL4RCMEVxDpyqL2IwUBvaoVJV70FQ+BY?= =?us-ascii?Q?ZVOQKFAndrGOPAxfSBl00hZuQgcKI59R5oIGGCyu0FJ+vJh2A8D+V//K8Yk6?= =?us-ascii?Q?zC2foyoV/CjqYSmitSuCYSWYTcv1m0guAzgoI3gozkfCS+E+l5D5BBCoFXxz?= =?us-ascii?Q?Ywje7p7AphXcqOGJCws045C3l3PASkd6+xZrSra8TA10O/0C3F+inpECx0IN?= =?us-ascii?Q?SwCbhVC4Edz4KkhXOgg6KOHMc2Ct+KNoQ3YL/AV2h7nRuGaLfrRH3tFVlJa4?= =?us-ascii?Q?544g04zavpWh76SDu+D363DW3AE0Q9/CupWCzLYud/qQpiC+fXlIjZh6E+M9?= =?us-ascii?Q?a/YKdeUUrPzCfgsI+xRjVvC7D443ROAccqjyDcNk+iSw1XgjBdtk845Gqad4?= =?us-ascii?Q?HjTOgyjxK+Ac8JsMG451h0sp5QqiR/pmGI+41BuIWjv0PXOabajllXNNAplV?= =?us-ascii?Q?k3kj1daddoYroDEzKJ0r5AEktDBqveqI8k/1ijXUZQZB8Y+7rzo34P3X6vg1?= =?us-ascii?Q?58WtLO13zVS+Exc+Xb8=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 22c5dc5a-f701-49ce-8797-08d9dcee049f X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB3823.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 21 Jan 2022 14:55:09.0495 (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: jvm8FIfdfRH5o+24pH+oRZf2iP+QtsaLstol4fhjKRmC14V8w/eofH3LonJ5Pyu7 X-MS-Exchange-Transport-CrossTenantHeadersStamped: BN9PR12MB5274 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --=_MailMate_377CFD2C-6BA4-4640-BA5E-D321AD0EA02F_= Content-Type: text/plain Content-Transfer-Encoding: quoted-printable On 21 Jan 2022, at 3:13, Muchun Song wrote: > The flush_cache_page() is supposed to be justified only if the page > is already placed in process page table, and that is done right after > flush_cache_page(). So using this interface is wrong. And there is > no need to invalite cache since it was non-present before in > remove_migration_pmd(). So just to remove it. > > Signed-off-by: Muchun Song > --- > mm/huge_memory.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > index f58524394dc1..45ede45b11f5 100644 > --- a/mm/huge_memory.c > +++ b/mm/huge_memory.c > @@ -3207,7 +3207,6 @@ void remove_migration_pmd(struct page_vma_mapped_= walk *pvmw, struct page *new) > if (pmd_swp_uffd_wp(*pvmw->pmd)) > pmde =3D pmd_wrprotect(pmd_mkuffd_wp(pmde)); > > - flush_cache_range(vma, mmun_start, mmun_start + HPAGE_PMD_SIZE); > if (PageAnon(new)) > page_add_anon_rmap(new, vma, mmun_start, true); > else > @@ -3215,6 +3214,8 @@ void remove_migration_pmd(struct page_vma_mapped_= walk *pvmw, struct page *new) > set_pmd_at(mm, mmun_start, pvmw->pmd, pmde); > if ((vma->vm_flags & VM_LOCKED) && !PageDoubleMap(new)) > mlock_vma_page(new); > + > + /* No need to invalidate - it was non-present before */ > update_mmu_cache_pmd(vma, address, pvmw->pmd); > } > #endif LGTM. Thanks. Reviewed-by: Zi Yan -- Best Regards, Yan, Zi --=_MailMate_377CFD2C-6BA4-4640-BA5E-D321AD0EA02F_= Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQJDBAEBCgAtFiEEh7yFAW3gwjwQ4C9anbJR82th+ooFAmHqyUsPHHppeUBudmlk aWEuY29tAAoJEJ2yUfNrYfqKMKUP/ifcU2b+hUQMYoOHzLnSLwO7cR4xbvQJeUG6 uq/25KjrNrTklFhOkM3BWZeBUXrNFA1lw8uRrtHEoMMCajxN1QDWxuR+ReO73/VH Z6RrXrzmqyHunscMGKTZulPPWS4+BdfwlqoPMZoRd8+7ylorxKMJiXk5WKMiUybF /SO18f2Ja8LeMGqQb+zbjPs/ljeDa9Cw+I8I0uMfr66Z/9shx34oRDMn9CgNSWgk QdDyZ9GS5lhXcE79qtBEdYmbA3GHrueW5Ex52CxbmOxAQQuL1bJxEg6VelIbEk4l WPZvVq4/4j54+/n9xlNqUsvfraAWZmiEnekvfm4k690PyOfJjLfM/lOKUWGRdSlP BwqTR8/hPgkOoB0Ffrpy0iiC2+1vHlaia1547hpWl8ULxbinIebdAyt75Wn9BA6I TFZm6eF6HSvT6BIfrR45Tl+UeRD6Uari+poG7QOAfs7UL79qFC5FUv9EINGLXsWs iO0DyaQRhRYSJafMgz8nuvHxnY1ATW6tIH4fQ1npuehNGQmkEw+He6BKYG0QM7QU SPgmawlF2aM/rRHPBwzrPuPOgQpLGJ4Zt+Brf2R7ebCdHys/CGpfZTxrCq5mNxXO Y1HTtkAoyRdoL3eJqpep3eRVdckcmlO8sxkRTmPxrXf33s4iKwCyimQpoBxqPThm 76Y9wpIL =XmVw -----END PGP SIGNATURE----- --=_MailMate_377CFD2C-6BA4-4640-BA5E-D321AD0EA02F_=--