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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?XLS9ifvJagg87wOumo4ACljULQOCKCLK83ELh2TgNKwuRH0QglESK9Z1iU8z?= =?us-ascii?Q?jTKdxD7kwD2/JSLx/xjEILgcjw82dwzs8J5hbBqOhXhr9LE0axJBA/B8f6F1?= =?us-ascii?Q?TcPwuUhwuFqBBO37k2DuJ8jyoiA2URWVtIrT0ZECH57HC2o1tzcmODgf4bib?= =?us-ascii?Q?ykY+c5AqRDbKqsRMzYTqAHprdwjE0H79rxKY3LL97cBuF/mGw5RL67/2KXIb?= =?us-ascii?Q?I14nNvcuvR3+4sL/Iht8bVs3rp9Xov2rLdp7Uyfir0Tb9dknSZHyLOLygkve?= =?us-ascii?Q?V8qlGa/cifsf8KdMvPX01YSmoeGd++v16H2iyjPaIYNFaCvLQMhENrJjNn2s?= =?us-ascii?Q?zLWV4/TOLa2dxptX+AWA7Dub/e4fRMpmN5F/2nZFgf+DxfNxywJ/eGtOaKwV?= =?us-ascii?Q?7F4sArC4U5VH/sO7oPumAB8sTGT+xAQMRH/rwyBxdlwGs74h+GfgCh/TEL8+?= =?us-ascii?Q?uJVWDlOf3EBYbkneULSr5wcjW2vtg7FImpTY7Lbbeif6XffB+9+LsbUY8idS?= =?us-ascii?Q?SWfXkihpk+94A/9xEaY9m/dmCMlpA8prc83ncm/aTjkXrHvGcuriKXKVzBiw?= =?us-ascii?Q?bDcsrzRcH4lB8uB6P8hPWOjaZCdnO5U6/BirOcM0V8JLeqK16/Kk+4v9Y1Oa?= =?us-ascii?Q?JSZ/R/eCB9W/reehLEumiYP1lU6vKelaJyhmFpEp3jyvcvWGx25Kn3rgY7hY?= =?us-ascii?Q?WG3IBiLXu1Q15oUnNJWPl/Vv4jQC7Atr0/BgjYvnYxsb3/2A4H+BZ8iykX/J?= =?us-ascii?Q?Am6x0Y0ONZHjDMF6pHMT14JUcccmTtYKs7HfJAmV2pzWYODo2KqZVs+8EnBb?= =?us-ascii?Q?H7H3b7SjmKHSMq4Nh3VYJZA3GT7CiYHk51wCP354pSLArKxuHrA5YUKncSq4?= =?us-ascii?Q?rkkI5UDf9myWxjl0Ubn47EJjYTZOlEO10Iv1XXtciv/yZf9Ww5+I9vhmNc45?= =?us-ascii?Q?+lAtPPXJBac92masfm5wb7z2WHTFPRqk+t1gM4QVNFwlIpymdlmqTdtlUDcF?= =?us-ascii?Q?M3bzBfXmF9/FdZpAlJ2+mQOkfDyJxHFnQtL4i1jn38dOhRg3wwHwySa/8N2c?= =?us-ascii?Q?HwWulIe+kwYUll0kgTk1Q77ukqUBo5urSqZBzfGRneZMFnZQVInyb/wAbYUH?= =?us-ascii?Q?fvSC4SnDMiZVaMudyYb0xwdAMx3hcZ9R4apz2BKcQ4XK3okgrZbrAkQIhW0j?= =?us-ascii?Q?NdSllo8FvC6SucHA8ttM+iMek8+ksx3FKlX2vcgZLwXOFYdqWETK4ghHheaN?= =?us-ascii?Q?ycnfisLvBlaLFapVt0kxMSR9ns06AyrhpbJ720A60zKeciANmmSArOj/rrlJ?= =?us-ascii?Q?5SvW8ZJkRFFjuQz0iMI2ATAQHoDQPicXm6UksXIDHoKmlzap1ytdRKNwMWT5?= =?us-ascii?Q?XXY8Znu+mTb7txgwlJWlisoGARccBrqZL8SOm51RP+ASq841WpIOuXpCKv/F?= =?us-ascii?Q?o4m939vB3/tlQ/2xE0HvzJ2CzZW+GjUvwh58biygVz2jyTppH7jaJI9L5KsY?= =?us-ascii?Q?7VtzvM6xm8sn8llE4f84MEfY0YFKLZpUxw2ZLFmeMOr6q5es3xBmIiCby69V?= =?us-ascii?Q?jEU8vkBgx49X2eFkxUt36yQH7EXFyISf9+h73tUQ?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: f2afb530-2f7e-4438-bb07-08de0fdde9a9 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 Oct 2025 13:38:11.8616 (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: kdKRc9DEt2aDM77CGU6iJ2NOpcz40VpMTpIhHBQuLDj8aT/+4yYS9kLf20VDqcP1QhB+uXsCSf1VXR/GYijHgw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: LV3PR12MB9187 On Mon, Oct 20, 2025 at 11:49:51AM +0200, Juri Lelli wrote: > Hi! > > On 17/10/25 11:25, Andrea Righi wrote: > > From: Joel Fernandes > > > > Hotplugged CPUs coming online do an enqueue but are not a part of any > > root domain containing cpu_active() CPUs. So in this case, don't mess > > with accounting and we can retry later. Without this patch, we see > > crashes with sched_ext selftest's hotplug test due to divide by zero. > > > > Signed-off-by: Joel Fernandes > > --- > > kernel/sched/deadline.c | 7 ++++++- > > 1 file changed, 6 insertions(+), 1 deletion(-) > > > > diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c > > index 4aefb34a1d38b..f2f5b1aea8e2b 100644 > > --- a/kernel/sched/deadline.c > > +++ b/kernel/sched/deadline.c > > @@ -1665,7 +1665,12 @@ int dl_server_apply_params(struct sched_dl_entity *dl_se, u64 runtime, u64 perio > > cpus = dl_bw_cpus(cpu); > > cap = dl_bw_capacity(cpu); > > > > - if (__dl_overflow(dl_b, cap, old_bw, new_bw)) > > + /* > > + * Hotplugged CPUs coming online do an enqueue but are not a part of any > > + * root domain containing cpu_active() CPUs. So in this case, don't mess > > + * with accounting and we can retry later. > > Later when? It seems a little vague. :) Yeah, this comment is actually incorrect, we're not "retrying later" anymore (we used to do that in a previous version), now the params are applied via: ext.c:handle_hotplug() -> dl_server_on() -> dl_server_apply_params() Or via scx_enable() when an scx scheduler is loaded. So, I'm wondering if this condition is still needed. Will do some tests. Thanks! -Andrea