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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?IwnT0HteDfYSOM5WwEgAwzPtI98ywYK3c7jU+JdyflcjToUE5Z0rtK9FdoQH?= =?us-ascii?Q?AUUEmr99huQGSnGB6/EDqwQUrHU2yBLPnjLlNNvVhDNY9Le1fQsAmVfjjH0T?= =?us-ascii?Q?LDv41Zocxi+8Ptoc89MZCaq8y83unumffAQDza+TejhLlf/XWCgm5GefDGJ+?= =?us-ascii?Q?74Dwh4HAXhg2JwqMmadIi9OZVU3YskW6fDhsjJy/oURXQjTHVzyXnkaC3DDn?= =?us-ascii?Q?nsJkEvgpkSHaxYQ7paxTtRM2BO2f+vVHL6JbctnLynouEIaoA6hxrFy0ykJE?= =?us-ascii?Q?wmMkkflKkZ1emXxmcXYBwccXeZW89fpiBI17QzQ5+0cybMqAFen9rQD0vw5A?= =?us-ascii?Q?65ObRzh6Hkd153wFdQUjaCqLksaHlpYJgUpYbP9Ov4oVsBg9dflg7v/ZXPbG?= =?us-ascii?Q?qt8ZvV/VukcBFQoSzgPBfV8OqPA2Ms3Vt4RntctJPYeb4pmjl8aoTh5YACIZ?= =?us-ascii?Q?TOKP/kLqM8jLLUZYq4uLflkQ8Lf5iFsSH4t2Jo9MpUdbn3xOzKdrUW+s7q+m?= =?us-ascii?Q?GzqKDZrucDBJrzMixQ1BUIZXj7/Xh8tHTA5w1Nzp+YkTMnmz7oWsKH68UdyV?= =?us-ascii?Q?S6H19b8aRx99VKmhm/5ehLbhe/RuYX+xmhBKod+wwYY/Heq+Z1vsM/ISigpV?= =?us-ascii?Q?WfTxePqeU97bxLXL50RErRz2Eh33h7tvbS8hyq2h/XZ/ElZRYhdf7DujT3BE?= =?us-ascii?Q?jCMvD0Mk2QH2RBv2upQCrulWYIc8N4qZq5USBVD19hXjVRRj6USmAFnip9gO?= =?us-ascii?Q?xj5tNgVUKwU4gmPNMvtjZyS+I4RhJMhQufAnBKbbGmvXZ4sxQ6iBAkWhPEyH?= =?us-ascii?Q?ImN8D2LjrhI2nS54NlTCXXi3/uwRIOFf5SDS9eoQzzK5vxfdMwAhqlQK2XZi?= =?us-ascii?Q?cXUKml0iKyrc7hMzwz44sTONyw7rFLu4mLSzp0KNWsBTkW9AjOgjxoIeDJ0T?= =?us-ascii?Q?w8a2am+0AVOenpmgT/As1toQk9bBAYm+0k82wyX+gOlPqe9iD+4BPEVPfOkI?= =?us-ascii?Q?76oC+15U6rA7A88omiUD44D6EV0o81SpM/FwPYhMy/Mof4r4jx3Na83XhS5d?= =?us-ascii?Q?G7gYf0+n4cdBQ96NkxjFnaA4ve/fOVnUwsEx1QLVmIJWIgdOCRvVU73h4joG?= =?us-ascii?Q?rZ373Dqz18K+8RHRT8s9Z96ROwBud0JEHpQRiUeoCGziVqTTqamhZ5iiEJ4r?= =?us-ascii?Q?5k03ULX+HhPKqBAkuuFofoW2/N3Mzwsb6MAol3Ipn5l9kI2INP7vPBGglKFP?= =?us-ascii?Q?CdUGkHMSPhBXjBsotoKDeR2dGovqR8U8v0B291X9ByWUQhv+k1XJTuQw4aZr?= =?us-ascii?Q?+G17Z+7sljpU9yYftYBU1+aTWA7XTqCkniOQJVYjEdxw8lCcfIj5smXpPkn4?= =?us-ascii?Q?mR0cFvpZewJrZdpoZd/wYWaMCB3hfm9103DHa0ujbbKxZ+ehuBruryKDZ5hS?= =?us-ascii?Q?c4yxcIhvKfEar3bZQZq0YQtErqxV9UFN6quaO4CY3JBbplHysjKjhKdYU0UO?= =?us-ascii?Q?UGlmc5Z/IA99xhbIhHCcc7WsUNyz5BaCrAaXj/mh0TdHZsmtLAjnMGl8pFnh?= =?us-ascii?Q?uuq74Eut4QskOjY/0oy+35qh08ZwA5FHmlQ18ZIc?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: a51e56d4-4140-480d-c6b9-08de125c658c X-MS-Exchange-CrossTenant-AuthSource: DS7PR12MB9473.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 23 Oct 2025 17:48:38.4531 (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: gVSrq/mXsioWdzISCfAgsKGREIIxbWqRWj3PHmJ/+LBfqfpjiXNekqD8jcJ9D658 X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS2PR12MB9750 On 23 Oct 2025, at 2:59, Kairui Song wrote: > From: Kairui Song > > The order check and fallback loop is updating the index value on every > loop, this will cause the index to be wrongly aligned by a larger value= > while the loop shrinks the order. > > This may result in inserting and returning a folio of the wrong index > and cause data corruption with some userspace workloads [1]. > > Cc: stable@vger.kernel.org > Link: https://lore.kernel.org/linux-mm/CAMgjq7DqgAmj25nDUwwu1U2cSGSn8n4= -Hqpgottedy0S6YYeUw@mail.gmail.com/ [1] > Fixes: e7a2ab7b3bb5d ("mm: shmem: add mTHP support for anonymous shmem"= ) > Signed-off-by: Kairui Song > > --- > > Changes from V2: > - Introduce a temporary variable to improve code, > no behavior change, generated code is identical. > - Link to V2: https://lore.kernel.org/linux-mm/20251022105719.18321-1-r= yncsn@gmail.com/ > > Changes from V1: > - Remove unnecessary cleanup and simplify the commit message. > - Link to V1: https://lore.kernel.org/linux-mm/20251021190436.81682-1-r= yncsn@gmail.com/ > > --- > mm/shmem.c | 9 ++++++--- > 1 file changed, 6 insertions(+), 3 deletions(-) > Acked-by: Zi Yan -- Best Regards, Yan, Zi