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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?ITdZJBbUuTzEGMiu5OSCorOo77oyPAvBX1NYL3lro0fdL6Dyn0SWyVQ78GH0?= =?us-ascii?Q?U+jSAPiUlcX8Semwzjn5fhGFoNbHStJtAcvalYbMDErR19s1/18EGcLSF84B?= =?us-ascii?Q?JKF+oE+StBMYBHsmkkvbpjVzDiNBMed5MN3hRQJmSaw61fBbjTDXtWKxvoVO?= =?us-ascii?Q?Q6nAckwVd/JprZckUR/ZFcNUjmNhKRI63Y3aVQ/9FMh3lt8czj78v6nifzak?= =?us-ascii?Q?AKYMR5slNvzVM8gUt7GGQwdtc/o1Cyu8C9xHtTC02Ct+QmC9lhbZti7R6S1Z?= =?us-ascii?Q?o/nW+5SPxkvO4DiaIPfcSGLooMDEnJ5Gd3YbV64Oa5EirhtsMKdTpNNsmKDu?= =?us-ascii?Q?lisa03TRk8D5UwqC/YG+kKOpv84TLHXUAqWzm+33fm98ZoHvl3jJp/RSe3Vy?= =?us-ascii?Q?Jiz04LGE+ctq1ySDA7EUXe1NKa6+2wV4wsrohwnUwD+EjJKECMAMMZs0r4U2?= =?us-ascii?Q?bbnbF/1G+TFNd60iRSM6eBNoqC5uhuAJAexmHgHB361MWmWzY4AgMrEol4Lj?= =?us-ascii?Q?jYQP0A7aUcBMVOdTntkpSsj0kc4AaRNesTGpsmA2Q43V1I/0KnGnEU6b5kZ0?= =?us-ascii?Q?J9jvDpnZ+uJv+K60q/+cKvf80XX9eZrQ7cfsqPIJqt3W4ECjSEtuDsCxwPqp?= =?us-ascii?Q?Ab4tkN88LygYE0Ncd9kGO1vW4ChnGqUScXCik2ckPRpeY1rq64S2uR/FYpBx?= =?us-ascii?Q?vdtYCnV/ffoSFnu3XXBq4V0mxP5IdqWMaaHbqmh13POGbnKn4emldXGDHNO0?= =?us-ascii?Q?B0szE3VCMoKY8wkpA/71DFov9a7NybzffcKXoD9cokTfbS5dW44nDtXvJaAQ?= =?us-ascii?Q?65tHZURJ0LYoniMr6jGXFdrvODM77wsqVRxow/jRkd2Dl04SLTSWOIQgJBNs?= =?us-ascii?Q?HP5LFqMfYV1LkHbdUMjotMHnVAYiRW31GNvCuyi8yODUlPFUPWyAFIV+2jxh?= =?us-ascii?Q?XWsnnqFHpIuVbd3OPManOaVubbEJkAl9LZxzM8IMjPdAVrXi3ifILNHeefEs?= =?us-ascii?Q?ft4WVz4u1CD9Px9KkDJLjxzPhmCxbYU38roLIYVWwzHOflkDvtqjb8v2B8qF?= =?us-ascii?Q?dk2nfithzLnDKy2TKm91o2/89ysm4LmBTXuKQEYHOjL5+N0UFfi/+jTXZp5y?= =?us-ascii?Q?lEe07tUW4tAhRea3zgwPT7OSnM3ddNj3kytEvBGtMoUrVirqyBYyPuefVc9M?= =?us-ascii?Q?zTwWTTDcN3pqg2Hh+/TS3aNmdJDQdBhZt+kOms3iBUQunqr7b5/+qY8LNxai?= =?us-ascii?Q?J55lYxBVBjQKtYEQisd5ElgK7bS97cMnkLcPo3XJGzeetYcEvy1svQpHitGh?= =?us-ascii?Q?Oa5sG0wE4XlP51DM09HKizt1uBz0JPTZDhLsA7d48RIzBANxYs04yqekgR3t?= =?us-ascii?Q?IZDRNnKzM58Q1PyJhmAIttmZ/JKNhQa5lHxew1fkTdilzEAe2SW2ccwVQ6ww?= =?us-ascii?Q?V1qRZZh00XzzNq6NqzyO4fariQfuNWMg7nG3X1h+5ZolBZC1pPxKIALPFYHg?= =?us-ascii?Q?W90iYk+0oYVguyhj1FnXqKOa3YTPmeMp9AE0drplYRXKGDkpSCyOYcnNL5fu?= =?us-ascii?Q?x9R6p3WD8HB56ppuLr1pKwli8IAI4ip6D/81ebFHDqsm1xFAQKv9lKl/LpyV?= =?us-ascii?Q?kczxyHKiOdMaEvGb+pePxs8GTHzqUo775PbFt7IZk7H4saFItDaxOyZzzws8?= =?us-ascii?Q?B40DS2VxIe3osUKlXr5v1dTSAfUlqyzyHC+fUp+ODcDUQm+F?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 9e323cea-f6b2-4cd4-a396-08de5e5b80a2 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 28 Jan 2026 10:53:43.0316 (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: sq7qSqcvdtJdERgfpc0K0jGtKYBhGZuYG2Ch5eKDSE0KfzmTT4NtzWWwyhs3vkotpmymQMMYpF6Ne2sQqMFPrA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: LV2PR12MB5918 On Wed, Jan 21, 2026 at 04:31:02PM -0800, Daniel Hodges wrote: ... > > Long story short, the only thing that was working reliably for me was to > > clear ddsp_dsq_id and ddsp_enq_flags in select_task_rq_scx(), but I thought > > it was a bit too overkill and then I've never finished to investigate the > > real issue... > > > > In conclusion, I think this is fixing some of these warnings that we see > > and it's probably good to apply it, but it's not fixing all of them. > > > > Anyway, I'll do some tests with this patch and report back! > > > > Thanks, > > -Andrea > > Sounds good, I hit this running cosmos on a moderately loaded machine. > I'll see if I can get a reproducer made and do some more testing. This is with 6.19.0-rc7 + this fix on top: WARNING: kernel/sched/ext.c:1282 at scx_dsq_insert_commit+0xf2/0x120, CPU#13: alacritty/6070 Which is WARN_ON_ONCE(p->scx.ddsp_dsq_id != SCX_DSQ_INVALID) in mark_direct_dispatch(). Triggered almost immediately after loading scx_cosmos on my laptop. I'll also try to find a better reproducer (ideally inside a VM). -Andrea