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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?M20BlICyxLJeLEqxOvNG3lUwffxOYOBE7CWTTiAbHhLj0qk2V8wB7bHp8jul?= =?us-ascii?Q?4TPIYlC0UrCwadKY9PMzoTTHvNbfhd4xmEOLW9aFmoPppOnsbZX219OfbXs3?= =?us-ascii?Q?MLIdtcI7cwet4fi6VSDzUkerw4N1lsmtAT6Ex429mu6jIX8cd7fl51luJrLS?= =?us-ascii?Q?l+kQcSM0fPWpVX0qogelQz2fPACre/m+tLd2QJ6/MoAXmlualhHm4aCyZvRu?= =?us-ascii?Q?2FwerOI/VWKiSTQCxv5NVK0Se6PUGRlThtVmP5jLWHlhJzWR0gsY2y9b6gYB?= =?us-ascii?Q?IUr2ZBSLkxPHv4+ilDOr8ty3/FJq84tORFvxMkBsGPzOu7UAcCJ250Ka5sPI?= =?us-ascii?Q?jHCuYwGSqg1T/sfpWzqvW/ha0la6aOSwwLN0nx0Qwwqi647PkcLPmR6LZlEe?= =?us-ascii?Q?KZwL2T9xQSIREPwvnLzmJ22sZ1glF0SM3yPZJ5GBNU74rtJV13J7FfiB7gWw?= =?us-ascii?Q?idwJVxwDT3Gm8gIdqZGDjuiRLxVFjY71tzOaW69c2P/coFcqECxmJFnwa+1b?= =?us-ascii?Q?KQQHPnq9uWqQPkhkn/wijLhopBR/1TY/YnUxY4Pk9cNNoDyKNGmmTE2oDrR8?= =?us-ascii?Q?8XXAaZ0Y7rS3IX1cIFsg3NaLMncfnMPHVDZGT0AFkPKSpE5RpzruMu587gJ1?= =?us-ascii?Q?A1btz0l0Eeid0Lyb2dy/40f9bmh//p7SLmSJ/MTuikezxp3k23GLfqUozKRq?= =?us-ascii?Q?C0gHu7OcmJRjI1XvVTAGslTuhys+tv6UEddBNAYeZYesAz93AFvf4F8BwiN7?= =?us-ascii?Q?aHzXRzBCblsWVx/kMwqqTkm6w4GM0bt1hRU5U4iUaSVyIWsbG7AML5OYUcYI?= =?us-ascii?Q?4O260WS4TcCXi9aXU7lQUl+20GZzI0FwzNHMudkgaoE/7h0zguTC7Q+1bhtN?= =?us-ascii?Q?mK0NJMc5tVheYT1jKqEdLLsn3Mk6tM4Y0fv6AWBTQjC1hPx7M1XIHCx5kn4w?= =?us-ascii?Q?isLhSzrtJFRu27azE7rwRVCyCYNnP3det/GiU2JTX4w9c+6utZlvdP6mt/qu?= =?us-ascii?Q?lM6Wr+pEhbHaEXrFtW9X0LNPHTffQlYocIyrTcssZFC7TQ1ZSfiZJBKzDdvz?= =?us-ascii?Q?gt0+DqgfPfkFnhkxTOQjb7PdLMO2KsXGxYJrKJ4l8Ey25xvfk6NbYmP1B4wg?= =?us-ascii?Q?kLwUlX27+Qtpe19/bElM81ED2nb+O02Z3cT1C1tZ3dhDOZ390DNkr1Quc5cX?= =?us-ascii?Q?b6wBgpGNF76bVPJyab7EWIyDFRnXX/Uw9k4xyALqSZXbthlxT0OO1Yr/lfyb?= =?us-ascii?Q?FuAL/N+DFBTA332FqZHnLpvWcbxEkxkcU0i6pqSblPN5Fbjq6KkPv5Z0OsfW?= =?us-ascii?Q?D4oL8s7+5XwsNcqPHsaD5T+Tg8fgnVdfc/cHBTpEKdE76zHvffFX+ng4oeLa?= =?us-ascii?Q?3MtmP0w+3dkAvLxATCYu5GGK/xMvG79m8OLKFoq7SaNjYT2h+PK3KNL8Vk8I?= =?us-ascii?Q?sbBy4bzeRjqexfK4BfkJwusi+z9PFPSUQ227zY4m7rnswBJstfskMxsmKZbV?= =?us-ascii?Q?Q+lzlFnhXAevetU9ToHIJWeaaXQj0W9Bp/i0qLMZlNoteU0uj4QXl8K/v4by?= =?us-ascii?Q?Lrti5NKRvFNihefXspP43tvJNsaWq/2bLF/HMMDLLPlR0IEC9ejGfi8KgOjV?= =?us-ascii?Q?5eoYh8bQElp8A0A3ZIYHDVJT7Atlef7zft/xWwmH8WwHf6iS/wToNh+ba1T9?= =?us-ascii?Q?5j1CAb4lQEdDGL6aW8ER+c4oAZAD+InXXbPWFsF3YvH9EpNo?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: b9929764-a56a-49d3-16dd-08dec97e237d X-MS-Exchange-CrossTenant-AuthSource: DS7PR12MB9473.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 Jun 2026 19:01:13.2447 (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: CtoaS6MQ5Hs9/b678ovgosSKpAexldb9g/SLJAx4V9fGE4R/dmUPtSPKgu9J2rYB X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR12MB6614 On 2 Jun 2026, at 10:24, Usama Arif wrote: > pagemap_pmd_range_thp() assumes that every non-present PMD is a > migration entry and unconditionally calls softleaf_to_page(). This > will crash on any non-present PMD type that does not encode a PFN, > such as the upcoming PMD-level swap entries. > > Guard the page lookup with softleaf_has_pfn(), matching how > pte_to_pagemap_entry() already handles non-present PTEs. > > Acked-by: David Hildenbrand (Arm) > Signed-off-by: Usama Arif > --- > fs/proc/task_mmu.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > LGTM. I wonder if we want to change softleaf_to_page() and softleaf_to_page() to return NULL if softleaf_has_pfn() returns false. That might reduce such errors. Reviewed-by: Zi Yan -- Best Regards, Yan, Zi