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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?Z9GdKVUz0zfxQkbYryjJI5zrCsX0GTGL4KfHV+8Z9/4PglTI3loQ2iDyfWdR?= =?us-ascii?Q?+nHAgULd181sNSqpip+ZteLid0uXgd2ji4Kh0FxF0tNSK+vc6uJqnFsBXo7K?= =?us-ascii?Q?++zmGj8w06Gi9ysHukzBeBd3Mq9qwoQfLrlDs5gHFQF2Kzb1FnefK8E2Jz3Q?= =?us-ascii?Q?9bSfSS8djWBjIJG/r1X+l/nIZQlNIUcS+OVgyN2yZQfvZz51EJej5YiN1r2+?= =?us-ascii?Q?E3hdCCHkuY1+rDtWkRA5a7HtEpUxJi9Rjvgxf48j1Flgq0X/kqOR8pOy3Dp7?= =?us-ascii?Q?7qOopnNkrolaSR1d3XfmJWn3CRkzb7RH/9QWDuYa/wsE5JA04IRABZX9tWvs?= =?us-ascii?Q?H9ZbaM1Zl0275UYHSCTl6YhoKIlOiSk5DyIBSH+ks+N2icEDrFEFo/YL6tLr?= =?us-ascii?Q?AXdwe6ndfnCWlpWc0uUCkAN1nE1Wp4R2Oof4gEI8RXFndevL0G/VJkZ4MRbA?= =?us-ascii?Q?nw7/YIecC9b4qfLPoUkekY2CdQSEnXrzHWDQhnugITyKUfr452TCV/oFZ48B?= =?us-ascii?Q?c3bDy0pkz7+OgwR7a0ayYFPv7YV+wIQkWrwEQT7j5GSq2dkmSMr0J3jcNCJu?= =?us-ascii?Q?zSUoilIxCqe4yWksb2NDUIbV4PH8IFFMVko40enVhfWhGHfV3cW75Lzz9iZY?= =?us-ascii?Q?fBiXB+Jn9qWjQgJt6b83zJ6t/SSA8J3rtGabEzJJ3YSL+ZxqyfPtqlVrtnzq?= =?us-ascii?Q?mTeOO0lbeph6Z93Y3P/B4m5UceVRY+RjIXcIqGrPCeRhaJC7VvIVeL/gMM6F?= =?us-ascii?Q?Ha98eTb+aZ+871k4RCX76tRYt0obOP0tHUcG8aqTdjFRQWKBapSd3v6wmsBG?= =?us-ascii?Q?ZiL1SO114pC2QqAWF8tlwCqZ1SJ8sJAiee3n5IyJyo0slUKzUDnAG3Yimnz1?= =?us-ascii?Q?PgIFO9L5VUCIsDlU/pQeEgQ5pH48DZfVeBiLLRQDscVekW1eN4VFxv5O2zot?= =?us-ascii?Q?QR/HbiZC7d9v6pjkuRG2MyFiDtKgISYlFIIhj8/fuAPOfeeplyhjtb2eRNsZ?= =?us-ascii?Q?4kNviudUFPIbVKsUp7clpKLAfP+VupChoic6Aok+aIFkp2MSya8FcmMotZq7?= =?us-ascii?Q?JN/6W64Drf9EExrIV7c8xNu9OrM4li7MQmqkrCpLNOLqRza7Z5r2I+sL2a69?= =?us-ascii?Q?kJr/nrgZlJ6vBc8LXJHKYS5pePu0A1rivl+CJE+rC9R+dW2OQDBgGy6nAc1D?= =?us-ascii?Q?c1syn2p7FQGWAdwDxRGXiDtKdG+td8CG/Xr/kn2w5clJTji5/VqkdmXKKFeU?= =?us-ascii?Q?OoXug93/QMOxq/iTQvc1WgyEErpoIa9hQ5FgBUG/jLvi5xwJeSWpIHY35m9D?= =?us-ascii?Q?pWILAEpCEo4q3ka6EdKoA7gX/IYT2vuSSzwpxPgXmOeJzM5v9Bxy939Mcbqq?= =?us-ascii?Q?bG/wocN0Aibw0a32aOGkBr2BEkhgc6KGEhSmXB/eqf+hpTWmr7QhZr0DZu9z?= =?us-ascii?Q?8LmCnxy3HebkXhEAvf4FbDPkGzk9z8qE2KEXXsaDn04K+OJ8M+c6ZqhoONWG?= =?us-ascii?Q?5kZye+zX6iVkelXzUe6Pl9XAQLVjsNwc3KtcNLJK4lmxr96T504LD5MQ5kQj?= =?us-ascii?Q?0ogehN4UOmNwTsoGF0f97u5niMmwp6aYoN3OzSjaxtHsl5G5xSgujK9Q5Lpk?= =?us-ascii?Q?GYJtfz45DsurQjXBm9+tFomoAXWx6E36ZXa57CTggKHr58rXRillPonwqrCX?= =?us-ascii?Q?0fapyhZ6fHfuO58GSWGRE+6d++LRNIDxMtL1QR2BVNM3XIrYNlQVx+JgSDa1?= =?us-ascii?Q?YZij08a/dQ=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: c4fb2c76-3045-461a-6ce8-08deb1a0c5d3 X-MS-Exchange-CrossTenant-AuthSource: BL0PR12MB2370.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 14 May 2026 10:08:40.8885 (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: 7PHQ85jPk7Qkby4oGsCuTbS0WYXKsEZouYp/lgnJOikwYxR50Wd8XGifK51EO0QCbkNM0vXVVkPu+QEpXNg+TA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB7378 On Thu, May 14, 2026 at 02:26:57AM +0800, Georgi Djakov wrote: > If __add_memory_block() fails at xa_store() (under memory pressure > for example), device_unregister() is called, which eventually > triggers memory_block_release() with mem->altmap still set, causing > a WARN_ON(mem->altmap). This was triggered by modifying virtio-mem > driver. > I see you mentioned about some out of tree virtio_mem patches that can trigger the bug, mind to paste the tree link here ? Just curious. Best regards, Richard Cheng. > Fix this by delaying the assignment of mem->altmap until after > __add_memory_block() has succeeded. > > Fixes: 1a8c64e11043 ("mm/memory_hotplug: embed vmem_altmap details in memory block") > Signed-off-by: Georgi Djakov > --- > > v1: https://patch.msgid.link/20260513130900.2204499-1-georgi.djakov@oss.qualcomm.com > > drivers/base/memory.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/base/memory.c b/drivers/base/memory.c > index 11d57cfa8d72..78e9600e6d45 100644 > --- a/drivers/base/memory.c > +++ b/drivers/base/memory.c > @@ -807,7 +807,6 @@ static int add_memory_block(unsigned long block_id, int nid, unsigned long state > mem->start_section_nr = block_id * sections_per_block; > mem->state = state; > mem->nid = nid; > - mem->altmap = altmap; > INIT_LIST_HEAD(&mem->group_next); > > #ifndef CONFIG_NUMA > @@ -825,6 +824,8 @@ static int add_memory_block(unsigned long block_id, int nid, unsigned long state > if (ret) > return ret; > > + mem->altmap = altmap; > + > if (group) { > mem->group = group; > list_add(&mem->group_next, &group->memory_blocks); >