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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?Ynyp1zq6OMXiO4gMpka2HiC6ge4lWq/LKMVLvmvtA6wHS1g/HHOn2E0vBsh2?= =?us-ascii?Q?7tZx0SJ/nVcguN+Aww1v1xiVQhMHL4jy7a9+/QxHWlpV2fe6LWfIlz8Rn4N+?= =?us-ascii?Q?DpAAjywXKxrwgw68TfqPmbLkVXcNot3tcRzeYCSeSDF2MARvNLukUoxAKTh2?= =?us-ascii?Q?9+CAOAcw9rq3oKg/eI/d0V7jzcPMrnU/d5XBTyyKuNDAdxPRDrX5gCoGQmdP?= =?us-ascii?Q?egr6fhr7BSZgxjisxJxh60TDkOKLva0B2lGv5BWbk0VmbaWR9j4bCxxTcFS8?= =?us-ascii?Q?5wE6zTC80EC5gFanjXLuNbb/KvYQ7GPdLz84gSGAWXe9DaeOD1vlB9qQCotL?= =?us-ascii?Q?GJm70TjBbH8uvPjkTUui58VEgH98oLwCmdtRPF9ZnB9ZcWDtGGcuJG/nAjim?= =?us-ascii?Q?poUe1vUUb1ONdO3/o+8m91unCF1xwDjHHXxZr8QPA5osxGu2Vy6Y5ZtbSapy?= =?us-ascii?Q?vXIC+kXKMJfPhocxa7EqL9x8qpmogMrscQhA02omCKy+VcgY1oetQmaF/NXY?= =?us-ascii?Q?sBwRTdyf8l0b7H0gZeQt0rI18AMaUOe3YicLsoijWqtp3CZtgKW4qyjZVAAO?= =?us-ascii?Q?rNv2LzUZjllIwqX9XtLgvhNBfszHeLuCYLgPiNRyHcXCe7RigaUnH2roawE2?= =?us-ascii?Q?lWuX3ieWhKCfiOUKe3dcnvUKyvmAeBkPRZjeYH4VPMbddvPN8T1ji7B7AmXT?= =?us-ascii?Q?qJYUWSeOx3AeOuv1w93P5G5TKACni6UWLRxUXJl5FunRln0ntU589ZKsHLAz?= =?us-ascii?Q?5+0pK4LCzy8PvarpCVWnl+scwd7TDAEgO76KVMT2RF096J7wvmStt3vFlKfr?= =?us-ascii?Q?cZfAVrFxFHOJ/L6+4ktK4KDq9dbJcqr2bAy4ESum33PaQ9hb8Bnl3YsY+Nuj?= =?us-ascii?Q?2V154hQsSDN/dFENzE07ZyQ+6ncCazZp//zXiAtsCDFAPYFwXzT8fVVQGmW4?= =?us-ascii?Q?pvNmqdhLsZ9fbYHScWXR7/dLj/HPTqhKHJRHuSeaExQt7QDKwYqbzlGqqdCg?= =?us-ascii?Q?HLpdSqP1muxbLw/H0He4c80/i99gkXe1iSdWedyjE2/bymcSUW9YNk5lLchn?= =?us-ascii?Q?9lkd94DnnJ1UB5lTeEC1uWwKaVvWVK4SwIzFSVe6ud7kIiziPx99uD5Z5YFm?= =?us-ascii?Q?HmIhDicYGQ21emDt+6boH9r6CHnU1vJHppmjh5ESCcSsA2RNFK+OEvrKZxwX?= =?us-ascii?Q?MBQhU74gHhO4LA8rOYlD6BJ6ZfPnZC0o9X6OLjVJmnTLTbDKhOfLS6+rhFll?= =?us-ascii?Q?n7Syg1x7wsEI2hPWEgRext+gdrdBxu+ss5K9J364nHU2PPBLBqHotc1L03H7?= =?us-ascii?Q?Xnnhr2K8/pSfg3c/pktVgUas6U42FQpZOubXBfaW6JQyntkTn5vS+CJPPrh+?= =?us-ascii?Q?un5P5fpp+WMG36ZTxM43OSt1Jz0+NY5DK2BwB9vE6ZUegTsz1TeatyAJEO9l?= =?us-ascii?Q?kZLHTGqbLO4Mri9DGeZf2owvbn8Oi1UbUqbXyzWLEIlaWiua8lGwzCuxm/bG?= =?us-ascii?Q?PItfZZQedE92oD1cnpc3kwO3OC5kGqwI+omt1kDen1Rl1L/758SBbrm0ngDf?= =?us-ascii?Q?/9Uv6UjixsptWC5juJDL9Jz575TwRy796sru6AEURmkckVM+IVJ21YdJjIxI?= =?us-ascii?Q?CbB7uqMmv+kpq9EUx0geTQPPYYAdHwdr/kWiR8zYtypIEeTfNHaqn1M1Ys7Z?= =?us-ascii?Q?CVXnWGW785fNCil/wYhymEbdcdqxkyluJ7UKSwcH6fj/i72aINIgCexJWslB?= =?us-ascii?Q?BKRttCjdbw=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 3bccd28c-59f1-444b-74c0-08dee07ebd36 X-MS-Exchange-CrossTenant-AuthSource: CH2PR12MB5001.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 Jul 2026 01:33:28.5644 (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: 0d125ph+Po4pCksKzmwQ0dxA2dezcBzJm0wWA5hUFou5DPmxOJ34tgU413rLqd2hjGFVbmJxn+qOklMxLwFdiQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SN7PR12MB7300 On Fri, Jul 10, 2026 at 04:53:48PM -0700, Andrew Morton wrote: > On Fri, 10 Jul 2026 03:55:20 -0700 Usama Arif wrote: > > > Since commit 368076f52ebe ("mm/huge_memory: add device-private THP support > > to PMD operations") a PMD may hold a device-private swap entry whenever > > an HMM-based GPU driver migrates an anonymous THP folio to device memory > > via migrate_vma_pages(). > > > > pmd_trans_huge_lock() succeeds for such PMDs (pmd_is_huge() returns true > > for any non-present, non-none huge PMD), so several MM walk callbacks > > that used to assume present THP or migration entry are now reachable with > > a device-private PMD. The results range from a VM_BUG_ON() firing on debug > > kernels, to an oops on a bogus vmemmap dereference, to silently isolating > > an unrelated live folio from LRU in the aliasing case. > > Added, thanks. > Thanks Andrew! > I didn't add these as hotfixes - the Fixes: commit is somewhat old. > Feel free to disagree with this! > > Sashiko went nuts over possible pre-existing issues: > > https://sashiko.dev/#/patchset/20260710105557.1987433-1-usama.arif@linux.dev > The pointed out seems plausible? I am working on some tests to catch more errors via hmm-tests. Balbir