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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?2KhbEZ49orar8SmWTVFxvohMV3xt5qf2hzCbRqrPcVPw3Z3ySAoBg/3AjAQi?= =?us-ascii?Q?bcdbZRwHGX906bc8uh+JYlxSsor74ovL4wcY/Jj9GyHvU0Ei+mGRvT4K61aB?= =?us-ascii?Q?MTrWZ6+kmc3j84XMrBh0Vu2RgwCM+UuQZ3U6Yel+yp9FX6RstE7/RFlgVFat?= =?us-ascii?Q?Lq6qxub5FWVpg5fNAewtJlKbHEMkSipVeRPn5kHJaHi6fuJ3s2sgQIf1YtTB?= =?us-ascii?Q?p0JSWLykzsv/yPwaszCYTRJ1lJCxr6I7gPUVlhPEIg7VWEdRO+LDxMg4HHru?= =?us-ascii?Q?LYoDKON995iC7HNfnpbtMBfype8mQYfd2U0RRHns5EtkdesGO3R327eJ8Wpb?= =?us-ascii?Q?vi/0K3S/iL1VEnU6kMGfmT5axNoMJ1dmqRzosAXOMS4SYXsYNBa2gZ1cHuAx?= =?us-ascii?Q?YHVS7rQJSZOPLXPYtWY9VbtZB0vkTe5JhLYZkyLeVmgUoidqeU76G25sO83O?= =?us-ascii?Q?AGpBxYjiEnCPAH8Q7kthjy/eZGB6HJm4Wpwp+7M9fMdGaz8yT4QU6bqUR1Vr?= =?us-ascii?Q?6nDhiilaxCDljYqDi7jfsJXbgIF4+pgYwbRyG8EvWEunWnIrhdAKKsO5ObVv?= =?us-ascii?Q?Pf68t7t25x8m2KIimA1cHP2AUaWV52Svwe+Z/IwIxksnZkxWoKh4ZVWOYx1D?= =?us-ascii?Q?qoGCGS8+qh40ACujV6yI/uYOrGrIIg+9umoQu1x6F2tZZZ8LT2LR0CFyXtE9?= =?us-ascii?Q?mFjYlQdL1ZvA/y6XeKdWznMPfXZpr78qDNGos70My3G0v7XKNcFWrZK7LMgu?= =?us-ascii?Q?iRLtJVo6DVWZGXtJfzsZQg/em+iwnNKswssnlDdB5CY/wuxScdn5y2qy4Mnn?= =?us-ascii?Q?a6Kf7cbjIN5nUgxIgKQsEHdLFcAzBHZVXkEu6zsv10yMPIEc6ww3vLD1rGPa?= =?us-ascii?Q?r1fxYBBUBKZC5p0egGDORV/XYF6aD3HqRtvzol0IF85AEmNyuSsgwij1iXLs?= =?us-ascii?Q?s+2Sky3Hs0tUt8LQtsoeXzAyq0a+QbUpOqK6ISanhCm1UR+PxDXjV7FsuBrh?= =?us-ascii?Q?NoTcsRHnU9w1bULJqPKYxCjBaM2ElhZ4NwzuiSNQziWh5o0OlT4O0zRpt39w?= =?us-ascii?Q?3W8bLpzxtgkUxl7KSqQtuhpIfTncOskhxqjPShKFjzJrIFmOjFIKoZGcP3ow?= =?us-ascii?Q?GbmygOecnE+TiZgOP9ajzWwDuEs/6+urWkenbG6eJqM40W59xD2k8uWgIFKj?= =?us-ascii?Q?0gCrvTCQ05JNkMzdpzIKN/Z/WBGRWy6UoH0TurnF1YnnsW1PT8Mg/yyN7nM+?= =?us-ascii?Q?dtu2RumK5GSQExpHpMl8YrJdvQXEWFxVniIxSCYVoLVpag/zCSC2UCv6gOh6?= =?us-ascii?Q?MlTSSjetWDXgeoh6ybaeVMmW8eBLGg+sTrOY3U8OcLrKoGimQz3vVBvc4LF1?= =?us-ascii?Q?JuQEDYTKc/w0qZ7W7O1oIGXYuv8AY/5EQHgtPVY0gcJsSYuAzJ2UD2yrLg73?= =?us-ascii?Q?OHhj+8ULjLwC86Q4ybogN0PRHGpatt4q3LUm/8+V4XFqopxWhoUC8jCGzIqO?= =?us-ascii?Q?JmpBtSBFM8wO1jshtZmyid2nHK8aULQD1SITfj+QYrs1/PjL4XfTHRG3Umey?= =?us-ascii?Q?FTuyhXHtDWf0v18Ws2Dm3C8mFWvbN/Iz1Jdmak2mVqsO8wC/5UAx/vkadDWn?= =?us-ascii?Q?jZzGNpaOvJxxMVsYCqxfOcBSBBmlFEeRQ7vDz15A5YdAhA8Im2oPJWt69CUY?= =?us-ascii?Q?tfD6nPpUzfGJxaLYalf7tIkAZ6x66syg4Kjp0QVqY5OBDelLzBWYiUpbErzy?= =?us-ascii?Q?i9+4UfCirQ=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: ef3703d4-f996-442a-5014-08def8afe925 X-MS-Exchange-CrossTenant-AuthSource: DM6PR12MB4827.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 12 Aug 2026 20:25:55.5304 (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: y7utbtRnbz7RA2oOb2Ya+zkRGrEIHTm8DaoUSEk/eXxALixJEa/3c1Fsvjp9UVpSYVt7uUPpR/Shtp9+mKXVFw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA3PR12MB7805 Hi Tejun, On Fri, Aug 07, 2026 at 11:02:15AM -1000, Tejun Heo wrote: > Hello, > > sched_ext's core scheduling support has been broken since 4c95380701f5 > ("sched/ext: Fold balance_scx() into pick_task_scx()") made dispatch run > from inside ->pick_task(). Dispatching can release the rq lock, which lets > core-wide selections on the same core interleave and corrupt each other's > state - crashing on a cleared rq->core_pick or leaving a dequeued task > running, which wedges the machine: > > https://github.com/sched-ext/scx/issues/3715 > > The main fix (0006) makes the core-sched pick return RETRY_TASK whenever > its dispatch released the rq lock, so that a selection only ever commits > picks made under a continuously held lock. The preceding patches update > the core-sched pick to handle lock-dropping picks (0001-0002) and fix > adjacent breakages from the same fold that core scheduling support needs > (0003-0005). >From a sched_ext perspective everything looks good to me with the updated patch 3/6. For the whole series: Reviewed-by: Andrea Righi Thanks, -Andrea > > 0001-sched-core-Handle-pick_task-releasing-the-rq-lock.patch > 0002-sched-core-Make-core-sched-flips-wait-for-in-flight-.patch > 0003-sched_ext-Replace-SCX_RQ_BAL_KEEP-with-a-dispatch-ve.patch > 0004-sched_ext-Fix-this_rq-assumptions-in-dispatch-kfuncs.patch > 0005-sched_ext-Count-rq-lock-releases-in-rq-scx.lock_drop.patch > 0006-sched_ext-Fix-rq-core_pick-corruption-under-core-sch.patch > > Based on sched_ext/for-7.2-fixes (d4a00d61a5c2). The patchset is also > available in the following git branch: > > git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext.git coresched-fixes > > diffstat follows. > > kernel/sched/core.c | 49 ++++++-- > kernel/sched/ext/ext.c | 302 +++++++++++++++++++++++++++++++++++-------------- > kernel/sched/sched.h | 5 +- > 3 files changed, 265 insertions(+), 91 deletions(-) > > -- > tejun