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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?9zOsTXb2BhMAS+uQ+8NSExXwBOusu6BjUSJM64FR5JcZnTf264vtNxcoLpaP?= =?us-ascii?Q?bSK5VV7iUFGSEa10zaNTJDHufjhAj2c048ToVniDoYtS8f1Mgcc4QniUqE2K?= =?us-ascii?Q?Z0lGEt+CvQrJ+4S8vOZeUpyn+oPnTyfI7kT22YuRSRy0nZIC+e+8M2fA+zXL?= =?us-ascii?Q?ca4Pb32mEI/M6atC4/Vl7zA4bmO0LZL/2bKh6QgiVSsrVMOUD09UVx/PyIO3?= =?us-ascii?Q?WmdBh5X47dHvxgCKWmcBdHSFo2Dbmfg3PtMFKJU/QsJZ62KeYdjIV8u/I3mO?= =?us-ascii?Q?ipctRKDVnw4vzuSOYhWqdHfEPxeEAHt/1Oyvx5h18Lze46W08G83vUVOtK5D?= =?us-ascii?Q?cZmdeukSGKVMhoJk3Gqph5rlUZhhjmvV1HI17zwy2Gh4+15JC7qSJH2Dp5nv?= =?us-ascii?Q?3Ar0Y3fj28n/YNm6Xj1wPUl7ncmkvJaqjZ+vXyJD615FPwZVvR1lSA/F5txW?= =?us-ascii?Q?WwCRjWwaLaajNDuunDQJae7M9x3m8I34gZJC+B76ZQcBJIhQXgRnYwrJ9GkE?= =?us-ascii?Q?j6baL1EzGpTwN9lPDhhtZwAo5VQ+7pl12BSfTxg75oPM35HyyNjmzilq4X6I?= =?us-ascii?Q?yooXWumsTJZ3286peminUsu8yuj3TR7BR2tzT3Yumyra+XvJJ219G+ycF3NZ?= =?us-ascii?Q?/3EgYutzvVcevymfu0anxVrxC62rGFEYVYsiZtXbrGki4cSHF8CsCL8l5Wir?= =?us-ascii?Q?9rZdyIir5lKD/OBBJmHoT1GqKy0HFMV6fIzhG/mU8CBM6pcZ3C4m7LL9S0Wo?= =?us-ascii?Q?t/hBXHwOmTkjtgsJkLtmMn8B77EwQkZ5uzwRRBgiBY78BfuK16UELQCRavR0?= =?us-ascii?Q?czd6+pt/xlvGG9HJ14pD3yFjNQPwXgMKS/WXtuMnoCZnIqjMWQB13K79fUgI?= =?us-ascii?Q?PmBCuYmnjFsI4uvxj1TvPBPvAF2gLx9MXRiznGL1Qse9T12NAs+HgR+VwiLt?= =?us-ascii?Q?J/q9J0mXE85/dF+8P9yE/cjasPcAVALJLVX3xrlxscOO+VoK6ssbsNwvVMLc?= =?us-ascii?Q?K98vzX2SYbvDuEI9QXD/DVWd9J1jc8GiftStCEWTjAK42zOUPMudwzowPMSo?= =?us-ascii?Q?2SWbIUe0B/w4igqmRaDJkeUfyAr4O/9APp9v0zz1XNPaR5Px/xxUDZPDM4O8?= =?us-ascii?Q?ilBc+M7btNzoXpkmoRn9lZdDcZ4JV1NPtySnNITY42ZlNFRX1jtwFxiip3pG?= =?us-ascii?Q?jZ5BEvySIzynftXWIzgb2SuUpPBN7W6KnMA6aO5x3+ffUX0bSoY1+MHhS8Jz?= =?us-ascii?Q?vf/h8yhS21UI+4Bkls/CgsnmFlBt7SqQoKhuS/oII8RCTngj4VgWEpYJeRF1?= =?us-ascii?Q?RRajQMFZGp2mp5jzsfkx+5rpIelcWe1jsRo2L4/Gce/yzVf8eSeS/6U9iXrf?= =?us-ascii?Q?L2lkKSRBuk0Jrd5fSHgXGsVNCfkct348raOCkUidSSgc0nH2+ksLUpHEXUMn?= =?us-ascii?Q?oJ2n5i/KavehFYM5JYfPZGGWAXZjlJlpAsLcrr7ifs+IjOLZ2iRJ84jzLhQ+?= =?us-ascii?Q?FuJEAewC1nT4rvWmltc4STZ+fmftbWfu6s7fLXRrfPKFoXaJlMneHp5DalnB?= =?us-ascii?Q?1mDeLSJmCtnbBZ9g50ij75y1nfmuJ9OEywpXfYB1AWaPBYyll7l/0Aw0DAc/?= =?us-ascii?Q?Bnm6MgRWCUdkO/Ti20HEBu7Vo9kDwQwLc5hjmJvErAn/WBHc7g3uf82UVkha?= =?us-ascii?Q?qsVl6E7Ci5p9o7xdhbB5j+nkQVIwTZCDdJ7Lv7XcNheSuZDRNFO8IVR5VPBu?= =?us-ascii?Q?2LakwPZ73Q=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 76241a14-dbe3-4e75-1c93-08dee74e1af1 X-MS-Exchange-CrossTenant-AuthSource: DM6PR12MB4827.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 21 Jul 2026 17:32:58.1248 (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: e8Y9TDBL8DDedXdE+ddk5cRickSTLG6/7vKCjvPxTALH2cGpMZDMEtq+TcuTbwWHVal01mNbJvcBVJOpNO4mwQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ2PR12MB7846 Hi Cui, On Sun, Jul 19, 2026 at 04:17:13AM +0800, Cui Jian wrote: > scx_sub_enable_workfn() drops the return value of validate_ops(). > When validate_ops() fails, the function jumps to err_disable with > ret still holding 0 from the previous call, so the fallback error > added by commit db4e9defd2e8 ("sched_ext: Record an error on > errno-only sub-enable failure") reports "scx_sub_enable() failed > (0)". > > This is currently harmless because validate_ops() records its own > scx_error() first and the first error wins, but it leaves the > fallback broken for this path. Save the return value into ret, > like scx_root_enable_workfn() already does. > > The nesting depth check and the cgroup online check also reach > err_disable without setting ret. Set -EINVAL and -ENODEV there so > the fallback always reports a real errno. > > Signed-off-by: Cui Jian This doesn't apply anymore, but the logic should still be valid. Can you rebase it to the latest branch? git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext.git for-7.3 Thanks, -Andrea > --- > kernel/sched/ext/ext.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/kernel/sched/ext/ext.c b/kernel/sched/ext/ext.c > index e3fa7b2fac9d..e623d6375f66 100644 > --- a/kernel/sched/ext/ext.c > +++ b/kernel/sched/ext/ext.c > @@ -7559,6 +7559,7 @@ static void scx_sub_enable_workfn(struct kthread_work *work) > if (sch->level >= SCX_SUB_MAX_DEPTH) { > scx_error(sch, "max nesting depth %d violated", > SCX_SUB_MAX_DEPTH); > + ret = -EINVAL; > goto err_disable; > } > > @@ -7580,7 +7581,8 @@ static void scx_sub_enable_workfn(struct kthread_work *work) > if (ret) > goto err_disable; > > - if (validate_ops(sch, ops)) > + ret = validate_ops(sch, ops); > + if (ret) > goto err_disable; > > struct scx_sub_attach_args sub_attach_args = { > @@ -7613,6 +7615,7 @@ static void scx_sub_enable_workfn(struct kthread_work *work) > set_cgroup_sched(sch_cgroup(sch), sch); > if (!(cgrp->self.flags & CSS_ONLINE)) { > scx_error(sch, "cgroup is not online"); > + ret = -ENODEV; > goto err_unlock_and_disable; > } > > > base-commit: 1229e2e57a5c2980ccd457b9b53ea0eed5a22ab3 > -- > 2.34.1 >