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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?auLOeLluG1rd2ip+V7CpFFZ71Z2VWHidUnfJYZs2O9JZGp0XWxjjRh+XJjZj?= =?us-ascii?Q?kjGAs5QoywYnlHBwYLCywldZF3btuZI45BLLj/Fawqreeoj+855Blb2asXad?= =?us-ascii?Q?A4w6Fh8Qe0tGBZ6nF0sQK06JPj9UWCTCCIpbZwMSD77gkwhmUmcbeEzz+cVe?= =?us-ascii?Q?UkV0uxN50d7nqnAy7gaNC9IKE++odKkwEW4hhJu+CKYE4hsFbfFRZvDFPxbW?= =?us-ascii?Q?qGPblbCV1JdZnSPSnKxrkJUxZg8nw0UAKUyQov91S84HAMenQNHiV0+cxcV+?= =?us-ascii?Q?kEzoAnMLa44dZZDCjs/MXF4f28egQtJ+ZYHzRd7O51BImZDB4YFzIWfF4y+6?= =?us-ascii?Q?P9qbdN06Y+6DOipZvmUr/GBCn5dOtllF6N2VAzlDyv9LI8Iwh+eIUkB3xb9e?= =?us-ascii?Q?0fmJWWuiWQJwjty4+oeTlC2tsueREeG0rhxMYohblgOZme6UzwZRL9POFYUO?= =?us-ascii?Q?SWsGy54LhPBCh0wckNS4DIHXKP/c/O4OZgGzm6IH26sjcifwjGO20zHVVbSv?= =?us-ascii?Q?UcRkomTc/Exq+qeraMIWbH+Nmx7AZx1RPfHhE+MhwTS0zyepZqXuWlhFi56U?= =?us-ascii?Q?Izvn0DQalyxv1CcC/KSZFit+pIH7mUhwRkDdcqTfsHSUDXrNfarZ+S7cEOp/?= =?us-ascii?Q?lCAb8XzAdevEgiH3hDsOCEmlEhBZ6nq9ghYp6LgtYfcd379dqkXtIkLkoYm1?= =?us-ascii?Q?9rgNJaiytExDusX+/M9P41XSCMUkZk4KrFKdlACFNjq/4kQfTr9UJAg4q9lu?= =?us-ascii?Q?igvC+18skG4oq08OFq8b9cZuc5kXE9j9q7fHh/2DB5qeunpU2xxDi1UsRcp5?= =?us-ascii?Q?UAVLXI+Zg786Y7m8eDPHL+6HnxldCWq8mJU1AIFuHiZ0Gf08gAVa2F9Xd+eu?= =?us-ascii?Q?1qYwnVGXFCKsXwBL/ab8CxLeWH5bRahYjNfL8c1gxUHOBDrpMFozz21y+UCz?= =?us-ascii?Q?qP+BZ/CG/V0dk4ewXh2f66h8xZXJVal1WSpjJ+3i+bo5kT0fDMrAoqWFGd2j?= =?us-ascii?Q?2+K8wauCwOg5o3nD1FjQZc4iSS+O52VnnRFW2yyXnUiEamoKfYiIhclrVXsZ?= =?us-ascii?Q?Djvwks7xAq9BMQaqXBUHqINCqSDmfThfh3JFI0mnfxAzD3tKWXC4z+7elEkN?= =?us-ascii?Q?GxQaO0I8oQnp3DLjS+jV5iDw8aUvQVqqU7LahUl5BcBQDjEXqzqxUJAFqrC0?= =?us-ascii?Q?Y4pnlOPUagVPgw7rjxHm8aVL12V3Wd9SPYYfrqN+CtVYqSrCjqvohdanVSP7?= =?us-ascii?Q?evsG/YNdd0MQlk4HShlPxm3TuGYSNGfAZ4yM4GFFubjJ2rTFJ+SVPjeUnrXZ?= =?us-ascii?Q?RMLjfoh4tg+rXgr9Tfv4LIgzSlnq6Kgx17rF+M6R5q4Pv0AJd1lkC2J+WqOc?= =?us-ascii?Q?3/XOVf4hcw/Mxm+yXJlz/hHJ8Ww4rwWuApBS7BeFFDTwynDYEw2MxlcjauAj?= =?us-ascii?Q?nVHqpEQmt6IPtISwzYlnMp+tKf824VMmKZLexXIwfqnkVfzaLcww1vzj7PDc?= =?us-ascii?Q?B2r6Ps3puEFWU+ZmVyarFCTy6bqcT80f50Ttjz46qTys8B081RIZkfDJPB4h?= =?us-ascii?Q?1/BPJZfXOTnj//XfTOlZXyBdmFNrkCnv+Ev77I8ynpQFtirZjzZ07H5DMByV?= =?us-ascii?Q?jWFVfslXVj6/QQnTah33STglUH1+z02TN10WTeXmVoKYkNFWGP0N0XZDeIn6?= =?us-ascii?Q?E2LOJkB91QRtlfLa9ARMgydwjlh5+n0Khh6s9ckELWKfHFzTmh7AUs6Z5wDW?= =?us-ascii?Q?YQdPhgX1Ag=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: c4846a4d-1ebd-48cf-a43f-08de8c184aa0 X-MS-Exchange-CrossTenant-AuthSource: DS7PR12MB9473.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 27 Mar 2026 15:48:29.3533 (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: l4bfl5llVAxu8IIjjIaORTgzdUxZ95A5N30bqRZHAagZu+Bzap7e3hwc4amZSG9Y X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH0PR12MB8774 On 27 Mar 2026, at 6:16, Qi Zheng wrote: > From: Qi Zheng > > The __mod_memcg_state() and __mod_memcg_lruvec_state() functions are also > used to reparent non-hierarchical stats. In this scenario, the values > passed to them are accumulated statistics that might be extremely large > and exceed the upper limit of a 32-bit integer. > > Change the val parameter type from int to long in these functions and > their corresponding tracepoints (memcg_rstat_stats) to prevent potential > overflow issues. > > After that, in memcg_state_val_in_pages(), if the passed val is negative, > the expression val * unit / PAGE_SIZE could be implicitly converted to a > massive positive number when compared with 1UL in the max() macro. > This leads to returning an incorrect massive positive value. > > Fix this by using abs(val) to calculate the magnitude first, and then > restoring the sign of the value before returning the result. Additionally, > use mult_frac() to prevent potential overflow during the multiplication of > val and unit. > > Reported-by: Harry Yoo (Oracle) > Signed-off-by: Qi Zheng > Reviewed-by: Lorenzo Stoakes (Oracle) > --- > include/trace/events/memcg.h | 10 +++++----- > mm/memcontrol.c | 18 ++++++++++++------ > 2 files changed, 17 insertions(+), 11 deletions(-) > Acked-by: Zi Yan Best Regards, Yan, Zi