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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?blh8CnWqcpwRQE9++PgEICqS6YbUkL3jnDhuwPPtttac9hZr9LmcPz4DBs1e?= =?us-ascii?Q?AZeB0A/+XQRZ3f2pP00iVQZXKxoqRqoAyluxOIfOZ/vEXTFDh3D1SQ9rTcVz?= =?us-ascii?Q?BJ55FXCzYibWUkCLs9BE35/QMbex1/q1ffR8JPm+PbHW8AGi0axA0YLuB4B4?= =?us-ascii?Q?Nx0ItiD7t2E1PGz422L/nx7ZTIAvMYC2tEhFYP33Dqcfkdhc/Q6f9iXJ9dkh?= =?us-ascii?Q?x5FUiXaW45Ciw69eQnpYzjA2sL0d1sHcAeq3E2Ls4HXOu9EZIy1R7i3LRKn0?= =?us-ascii?Q?MPvxeU6cpWYOu3weiYyh7vNgKhv7b3Z7Tg29TKLWXlbEcqt/QG4SGHHbdmm9?= =?us-ascii?Q?oIPRp9noEX8pJ2Jp+m6MPxPFTAVJKQkrLXDPN7bjQh5GpCqm/bbEUiot0NMi?= =?us-ascii?Q?APBCBqrpZla4uOVOX+FoTVuxo3nsCgjMo2H9eGs6KqzCp0iCUkFZoIz7qd6x?= =?us-ascii?Q?Llp1H0c/6bvHdD9cnBQson27JHAXrbtbeLkH2ZXPcD9M/Xhz74VYnOJnyA7y?= =?us-ascii?Q?juk+jzNbDI4f68c1/3mK0anBMSMxtmRtai/6A56BEoQE+ROlSjtvYxV6qhTY?= =?us-ascii?Q?2hRc/AO7+dLFDGEpOb06OB1BHDLkExrf6mSv2BXqEg7DWLE2xn4t9gEARbxA?= =?us-ascii?Q?DPgb1vtDlZaSWe0OPb43HsV6/V0rruM/+9++EbMVrsiDHOgbChFdpjl6RFrY?= =?us-ascii?Q?GyXeNHGh/UfWKOR2LJjWokznm1KYNoBC2c5AHh20dx0DRxbVrCsxkFNk8J+B?= =?us-ascii?Q?Ia3ywQI6Yvf/03kWsZMFpCr5R3XvoZv3u86Pz1ua7NXLkVpfVPAiwLlCZpF1?= =?us-ascii?Q?ii6G5cV/V2ZXE0nbZM0We5pv3CDckn56sj0f1EkMMiz70AAQefSnn5luKqlm?= =?us-ascii?Q?HzGFGQjxTeP2idj14fOPs7GffsURziSGP2SzqDxq6pLh7omEAfJ02POrfLgi?= =?us-ascii?Q?bThGhKqzR1/Dgui5AT6Hk1j+ZCzNkaoL8et7Q0rIVezu2lbZcGHHYIEc0bHF?= =?us-ascii?Q?a1gaZN6xZtdw9j4a+RY28pZzhqxHsvESrobanWQJeOzf2/CdNYQOV4YwnCSq?= =?us-ascii?Q?8/LOYE9DM41pQM+ny0DlV4X5E6eX9g11dXbqjGDaSoVC/Y/0uZMoGrZvyFGR?= =?us-ascii?Q?FimLcrC+xXCAlsiBam1kP8b90OaRQsuIBCB+zYYSZ0gu1lKqZA1cjlj7/Doa?= =?us-ascii?Q?pYPf0yLaTmi0OYv9RyjjVhbhAYQ10gAKvTukkSvRzjEVfuXR3CIF9tkCna0w?= =?us-ascii?Q?AjoUTff+1DUPicP22VY6HyqE9OTRR2USJmRILHm3CecnEoWxhguyh/kEHHWq?= =?us-ascii?Q?htwgsIgpfs2p8/8dGNWy6MANrDPDRx7PECMz8aMbpFw6IRMwAvDa3a/vTLEh?= =?us-ascii?Q?WEbKHg9RRWi2PB65UGbge18GChPHChDSkGxTgOmgNE/gKTXQnpJbrmCIAAe3?= =?us-ascii?Q?RPjOzv+4PSSNXOxfF3E0Iog9lgOLYBjY86iVFdpAN621A+Oiy1jHC58sCRzb?= =?us-ascii?Q?bqQYixhfXFJV1SJ81NpDtnZvLUnrWGQXxqsOOeTZlggbf5dO+RwovZUy3Gwf?= =?us-ascii?Q?fSH8YHEYohz5R0YMMiaZXF367qAVEmoEuyRCzRVO67OFSPS/fwdY5vETdvcR?= =?us-ascii?Q?7Kxcqa5BHwNTnn6pUFeeiTytqu3oOWgCGdda3DVUwxAYygGQl+Pubt6SpXC/?= =?us-ascii?Q?d3cAcT6+HXGwscOd/1dhqX+DLeBjhLDIAtTPXEaQu/C7hYrrEDQt/BmIeher?= =?us-ascii?Q?Vvo3cPQEJA=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: a73c4e69-9c3f-4ef7-4476-08ded85e1df6 X-MS-Exchange-CrossTenant-AuthSource: DM6PR12MB4827.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 02 Jul 2026 17:19:47.5851 (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: K8JBAWRJq8r4qBv++lh47NH1K76vJ0Gz7IXcrA0gam1On6HS68c8ocqOeyDOpx6etql4AbIul4KT5NXdu69SkA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS2PR12MB9773 In __schedule(), the proxy-exec donor-stabilization block calls put_prev_task() and set_next_task() when rq->donor == prev_donor and prev != next. For sched_ext tasks, re-entering set_next_task_scx() for a donor that has already been seen by BPF ops.running via the normal pick path causes issues. It fires SCX_CALL_OP_TASK(sch, running, rq, donor) a second time, and sch->ops dispatch can land on a vtable slot in a state that yields a NULL function pointer or corrupts the stack. Fix this by skipping the put_prev_task/set_next_task re-entry when the donor is in the ext_sched_class, since sched_ext tracks curr/donor itself. Signed-off-by: Andrea Righi --- kernel/sched/core.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 8a3eecc7caf5d..2e4c98b4ea6b0 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -7185,9 +7185,14 @@ static void __sched notrace __schedule(int sched_mode) * anything, since B == B. However, A might have * missed a RT/DL balance opportunity due to being * on_cpu. + * + * sched_ext tracks curr/donor itself; re-entering set_next_task_scx + * here dispatches through a stale/NULL BPF ops vtable. */ - donor->sched_class->put_prev_task(rq, donor, donor); - donor->sched_class->set_next_task(rq, donor, true); + if (donor->sched_class != &ext_sched_class) { + donor->sched_class->put_prev_task(rq, donor, donor); + donor->sched_class->set_next_task(rq, donor, true); + } } } else { rq_set_donor(rq, next); -- 2.55.0