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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?koCi8JTqv9NbbX8hG3maKn2AeS0qL8FPKSSNvujYK4Ev9Ha/Dp6pDbuUQ0uH?= =?us-ascii?Q?jz5hHGHrqfTkQ9Zomwhid/2aw39nJWmHQ7MPuXSMTy+MLwHKHgpOUgns+JXV?= =?us-ascii?Q?fX56CImGZgeN84QIYit4iXn7XoZThfQM0DusPa+6Jtg6uyX9qSaKRBqKp++j?= =?us-ascii?Q?n1hy0iHjleatI450Xb7xXuXvpfDs9iHgh3D34j02W0dfMZEIpS5xjA5BKpfR?= =?us-ascii?Q?HJ0wkG9tTALhyAmyVzbxiD8VZBLo+ftxhB0Em0abuT9/jKQRas5Pn/EvDNo3?= =?us-ascii?Q?KqkbAq/6wTDLBCCaV1eFLF3yQqIBTvqh445t6T7yJigW70zPAgTv6c6o3TwJ?= =?us-ascii?Q?iV8ytymEgZQPUoqTHGMX8Z5TQrQvasF73j4hArUQdPyZR27bzk1Ni4c0ce1V?= =?us-ascii?Q?Uk6RilZrCknGskPAs90XtQAAp9FfYmBtQyUoOLFiOtPC4StmOhU/NHHDatPT?= =?us-ascii?Q?mlOFyOfQ5a6qKoR2lI3qhA1wNJHqiqTaPjVpCmOjiFrjk4IpYed2zP7d3wlH?= =?us-ascii?Q?Q3JML/NGI3fE/X4HODiIM3/H4pPaukCInSwQCpIR5bxKVAlfNtJjt47CgVBj?= =?us-ascii?Q?IfMleAXKh0UgWI4P9BWjmRSthIXAf4QByMFEi93On1XvwDiJFhZYTLP+02NL?= =?us-ascii?Q?UDMBOaV2vrJzZ2heOunZx39eefR2ks3S3wjM3K2obBwK8XEtyLqqe4w1cD3z?= =?us-ascii?Q?l5Z64m6f5FuTQJzt5e4fk8Rj4EcVwlaM0nJkDTJgev9eKuqJyRhd35m96+CK?= =?us-ascii?Q?/fBSRUmB+WYtlptSutWqMAGrV00PKXPTjHhJRdjIihdkNL8K8B7K5jyUO6fx?= =?us-ascii?Q?l4dnlqgM0P8tWaP/WM3TaZNEU8OHmD/JYsYYUxB8lNuXb01dupCv3/LdfUbU?= =?us-ascii?Q?VaHsHWOx5KuZOxggyX5v0GtN+VCv5WiI9/VEl3vlsm5XQwDvgSUzIJ36hY3L?= =?us-ascii?Q?2l+EPOz8Utg479t4q0pryw71IeSVrdC4GNLPCPobYTgwYz0Kros/3qW2EvOn?= =?us-ascii?Q?R6JS3P6BjEEqjxF2mPG5WQeXjLyYaoUBz91gCpUSy9vLucIYYk1Xv0QicPPz?= =?us-ascii?Q?zrILPUnk6TRnYnxrF7lH9Kt/Ez96ibsbQKyctF1qys5I9+kHVBtJyPaL3VeP?= =?us-ascii?Q?4VobnjGnAM9EL61szuVEFxGu+OEsHNCWXB3ka7azK7J5CNSU1zP9qlO68puI?= =?us-ascii?Q?ehCneBxikEe4awBe0oplIPG4Rn0sj7+aHm6kaeD8PC/hQzH3ThFYI2MOGQbQ?= =?us-ascii?Q?MJLxmOFCcM+g10EJGRTSw1pDtKCW5w+SRRtdPYIxCclh+AfPqyxjYB3VEnyp?= =?us-ascii?Q?1LYGHO6jCVUzLh1u3Qyjy5kFmWg7KYzqHTGDwX1B9ifXDIo084Gi3QH+zFVO?= =?us-ascii?Q?mjvEf7gOQ6bbVXnr/imvuSSymAtDI1G8LKIjCT2Il/zb2MgTw9v+MP+ZRpcm?= =?us-ascii?Q?8ZPah8yGY95Qmrk4iFJPCCbZ/wz4/7wZZF8j8vopo/AUhuGhQcUDzE+IUz66?= =?us-ascii?Q?hqDXFAxm6n314IEjKsOKgmeb0EguCm56wBsB0S1U0EnQ+eZNtfq8SuUbp7Su?= =?us-ascii?Q?DKdL1F6LiVdCRmoYa0fT61WcdEM+zuu3DT3kLpyeBS3w0TWix66ifUfKsSkQ?= =?us-ascii?Q?57s/emTZprRENkAjga9RzbFp6paiOroRL9g77lPp006EjYD+jiFMc18NwFWT?= =?us-ascii?Q?0KKSg49WUG20wn+AeLrP/hvhJLvea4IjU8S9a2G/2XTCnhUc?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: c76b85a8-edbb-4d3e-3eed-08df288c3034 X-MS-Exchange-CrossTenant-AuthSource: BL1PR12MB5174.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 12 Oct 2026 18:11:08.1703 (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: jpSYpdoEQqY0S5BJAS5pGsrnXZ3WsRIEfXrjY5Uh0aAsRNj/Kd0R7KEsa16H7LEjdE/KFAz+TLoVj2zBVVa/7Q== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY5PR12MB6599 On Sun, Oct 11, 2026 at 11:40:26AM -1000, Tejun Heo wrote: > Hello, > > scx_bypass() propagates a bypass to the descendants, and claims bypass > dispatch on the host, only when the scheduler's own depth crosses zero. A > sub-scheduler's own bypass that overlaps an ancestor's then misses both: its > descendants drop out of bypass early, and its claim is leaked or never > taken. A PM suspend over a sub-scheduler's enable trips the WARN_ON_ONCE() > in enable_bypass_dsp() on the next bypass, and one over a disable leaves its > tasks on the parent's bypass DSQs with nobody consuming them. > > Patch 1 propagates every depth change so that a descendant's depth is the > sum of its own and its ancestors' bypasses. Patch 2 claims and releases > bypass dispatch for the propagated descendants too. > > Verified with a debug patch holding a sub-scheduler's enable bypass open > across PM suspend cycles: every suspend landed inside it, the unfixed kernel > trips the WARN on the following disable and the fixed one does not, with the > sub-scheduler's tasks running after each resume. The claim protocol across > the PM notifier, sub-scheduler enable and disable and root disable was > model-checked with TLC, including the sequences fixed here. Looks good to me, for the entire patch series: Reviewed-by: Andrea Righi Thanks, -Andrea > > Based on sched_ext/for-7.3-fixes (069403dff337). > > This patchset contains the following 2 patches. > > 0001 sched_ext: Propagate every bypass depth change to the descendants > 0002 sched_ext: Fix the bypass dispatch claim for schedulers bypassed by an ancestor > > The patchset is also available in the following git branch: > > git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext.git bypass-claim-fixes > > diffstat follows. Thanks. > > kernel/sched/ext/ext.c | 54 ++++++++++++++++++++++++++++++-------------------- > 1 file changed, 33 insertions(+), 21 deletions(-) > > -- > tejun