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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?UE/XbYZtSbkpplck17wHbi2gM3e6m0ZjB8BJcJPaLuDROlX2b2Aq0vBQLnJc?= =?us-ascii?Q?PELMtHeL6Sd/dd/xZx0Y/nizy/viz0JwDHk6gffMTbCO0vofGPS6ZlcX8VRQ?= =?us-ascii?Q?jpTuCtPXItS95xD1vt8/OM74l4/ghW+fqUFxQERvNCDYKskeGmYGF8I8Bmdn?= =?us-ascii?Q?l6Wc0hhY0Y06b0XXdSVQq4w9C+w2XLEbR58JeOwGi7I/YR2eYGj6Ad08RdTb?= =?us-ascii?Q?mB9sZTnIX2TVPYFc7aSMsAkPZlxX2dKZp/Xq2JBvDjy4YwwYHFCkcu1o023E?= =?us-ascii?Q?aVb/yoaONPh24+ocrLtyLLl5/v/UfCJpaQITYvjNVqgv5fyi5DfYm3IVf4/Q?= =?us-ascii?Q?n1gvaxm8xyGbhS/raXslSFjFU1BCdUD9747IGCEeVjrI3bKoxPO40VA5iUF+?= =?us-ascii?Q?dTc0UhErZa1oPxO3KOu8+SlspK7HzgSzeQGiIxCu9wEX9zv4j+JddNqbsvC+?= =?us-ascii?Q?gUPXj1BqLWJg+7EOBZtKpssXkar1JZViPu6P/SVy+8Uc24pAknHu3/mieC7A?= =?us-ascii?Q?2AI7jse4sVVHRqU2ApUrs9t2+mczv5oZXm5xEbHeRIeu3dYRViW8nf6jMKdQ?= =?us-ascii?Q?WNcsUszqGniNUvqHm4O4uMI8zr82ukxk3vENAfuSS5Kc3OAsBT/K3s7nSCXe?= =?us-ascii?Q?NALG6WBgWGyuth8CSqyaIJlqs7/yOv9agw00ouyhtuByl746c6x6TYuWthRg?= =?us-ascii?Q?fBfnrRQEUicM0KYC/CC/eSUKXWvh94RgnsUfnGaTV9Sr85IrmX2MJKnD8YMu?= =?us-ascii?Q?XhEQI6lDufz1jxhS7Fb5lZoZXfWoLfI/NxO7Gs+BVDX/gKY6d5atAwoQ82rj?= =?us-ascii?Q?G08hL0Orli2KpDDIQSafF+dovoh6BDHMDZGdUzjaJ7/wKQxglnjZ/bR6uARa?= =?us-ascii?Q?LX7B8AfS4ETR8aqwOScUkoouDW8gpEriz6RsWqQVdGrb4iWH9fbyNVT6MUcL?= =?us-ascii?Q?VdY16cDVDqyas79GMHAq6wJWNpa71z5WU5v7lT3gv5UkmQzvn9iDiBo1bGbj?= =?us-ascii?Q?YdAXYa4p696fodt2D3e6LdemMZqqSwjTTsilN0F9Rd5ZJAURsZmXBnqgGM9p?= =?us-ascii?Q?dfdx+WnxmosnNKxEPgcrmBX6WcirJhEoQzVBmkD6KvfcCsOYrVaYhVL4FIdm?= =?us-ascii?Q?65O+3bSBzSPzSFaraOUQQgqLn2u0Ts5RS3f4DcsbeUKpr2odAKSm5dEQjhBV?= =?us-ascii?Q?P15eXH1gRKukCJ7joowfUQ05WWrQJ2s9pjfe9A9Uh9+jHT1i8Ax4oVSrVehW?= =?us-ascii?Q?8e+6vwT7dO4/qDRxY2kQ0abxgx4evbR+4eunz4KtmaNY69DyYFkGygp+2T+v?= =?us-ascii?Q?IRRZzHUGgYMrJFJxiwNNV5ZMdi+eiPgoztYrFTklvj6eHZWeids/6tsPUoM7?= =?us-ascii?Q?d3rq6EObF8Lbt1H+QHjmejzJPKrCwsZkDJjWYW9DFDFaTgAgcbJ5v5Cs0cAq?= =?us-ascii?Q?wqvdIY3b5BewE/DU8bTZ7PckxudDE4TvcxHqGjn4WWCugu+DeKiTMCuM8IDq?= =?us-ascii?Q?qP0yB/My9OTPUR3oT7g7YooY7M+rCl3ak52Oqu8UZrAuWudcKd2KC3VyZ+f0?= =?us-ascii?Q?yL5UsOpG3sNS4f7SeU4CYqRFiH/Q1PANTceQfjht?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 8284dfa9-a6fc-494c-fc95-08ddeafc1549 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 03 Sep 2025 15:10:56.8070 (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: /0qmXBFjfCb/VPxM2AIHf8zIVBAgmd3Qa75pZF3X6QUt8veN2P2aRHgw9SdPPwBut3MzlEyCp94N9MjoFgcYlw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: BN5PR12MB9462 On Wed, Sep 03, 2025 at 04:53:59PM +0200, Juri Lelli wrote: > Hi, > > On 03/09/25 11:33, 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 3c478a1b2890d..753e50b1e86fc 100644 > > --- a/kernel/sched/deadline.c > > +++ b/kernel/sched/deadline.c > > @@ -1689,7 +1689,12 @@ 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. > > + */ > > + if (!cpus || __dl_overflow(dl_b, cap, old_bw, new_bw)) > > return -EBUSY; > > > > if (init) { > > Yuri is proposing to ignore dl-servers bandwidth contribution from > admission control (as they essentially operate on the remaining > bandwidth portion not available to RT/DEADLINE tasks): > > https://lore.kernel.org/lkml/20250903114448.664452-1-yurand2000@gmail.com/ > > His patch should make this patch not required. Would you be able and > willing to test this assumption? I'll run some tests with Yuri's patch applied and dropping this one (and we may also need to drop "[PATCH 10/16] sched/deadline: Account ext server bandwidth"). Thanks, -Andrea