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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?f+gwQVAqTnuVEHNqq7PyUfg7N5d/cDKxmqx65qXCPncSZfyfJPZNT06fkUi3?= =?us-ascii?Q?4/eMLmI7RE76mikIoVOcGmPTcedi3+oLKJnUrj5m2hD1vWJZcI8Oa050t5qX?= =?us-ascii?Q?PKYh15lrUquGamPowtqHJzojKa2C2anVPjV1NmOE8CywXORpfKRPPsvBdqmW?= =?us-ascii?Q?vSuGq5vcez/Obdhe9g5nqPAVbJlviHE9hf/9DqDFNqCfyMtURYf1RbCV12A0?= =?us-ascii?Q?QA+Z5jA5uee6aiXcyRYwvvKFAY4F9WjoMF5Sv3vcDdXYrozKzX/CIC/6HWTA?= =?us-ascii?Q?9+6G7bTafshP3Xr+HV5NKDe8NMYh/P9e0EH/AyfuFnkUUp8OnhM5SqTFoYOf?= =?us-ascii?Q?1ueVad1rgatRVrWrzdpcp2LwISSOYgAci96EjAbPfZ8VZE4C3fGtaIeZlzSv?= =?us-ascii?Q?lqT1AN2RPISpZMwoObm2sue8v4B4UXAzKcuvxJh5YkTugNctwJueJrH+iET4?= =?us-ascii?Q?a6bhozgmfNP9ISD8o1p8DnwCPSWTwUM3IlDPwT5f11N3xqGo4+kWRDX9+nNl?= =?us-ascii?Q?duv23puviDHqigKZmRh3WZ2hZ4hsfChMH/87sXfImHs/V607oIgXIh/ugKyR?= =?us-ascii?Q?YlV3HCkFs8E03cX5cAJDas+/nFwxr/vSPVFIIdggifiRGo5aomBHD17x2/Bs?= =?us-ascii?Q?jx4Kiog70aMvF8Dx3LHg4ZBjFGW9A/0OLUTJ0xJv+yAhvznSq9nDTrWRc+Yz?= =?us-ascii?Q?Igl1X5R5EqPst6WmMZ6BwDLwPBL7wbaPj6aQD8taPlfB5g1Xna29BBzxOqFL?= =?us-ascii?Q?XY1BfOpyi1Y0FEjifyEibfbmabCuq9WgQ8tUuWzJHvFNhwJZ4H62QedBceU6?= =?us-ascii?Q?yApbcdUihXcTzT+qHXXKeS4BUszZVUbhcOYHrh/aqkoNeSVpH6h2fToaDI7i?= =?us-ascii?Q?vJ76E8nF0nmIb1ZdyH0762tvIitwMp2zXXNe3HEvWaplR75SdCC2PJruZNDT?= =?us-ascii?Q?TWw1JxFSrAekBgxtcxytl1dtOeyVN9EJS5LnJwUwvsqkZ6Seq65jhalftT2g?= =?us-ascii?Q?Bbi042bJm23y24kXbAAJ0FZ6vEutaVAi49K6vRloABdMWHt5JREtCUCFHT0G?= =?us-ascii?Q?90/qXNeZhJ8ECWEV5gNgsZm20dWlm5pf93mSpB/CZSn2vwx4gTwjcOFnzso/?= =?us-ascii?Q?bbblr4XltMWr5cJcdOKsZY5pEhh3oSkWOm1u1C4vwNQ6GumrOUR5WbRhKGTV?= =?us-ascii?Q?6SjhFq5crpeocFakCiZXM6a81kSJkM/aS4amTt/dMDEcc8G6geHT/dYyk2Un?= =?us-ascii?Q?YIMKG4vjhnKv0IoVuHYj6uRuGafPaBGXIpz+OSURzVqEXM2KzrPzZVHvwBp7?= =?us-ascii?Q?JvUrctVSQPuuARsWxprf2dVBvFtM+dV30ABTEDveV+4urDI7Id8FqzP7RgYv?= =?us-ascii?Q?BlBKRua1NRUwYM2D5ZytK71Z5XXkO+BQOqS3AumVSEVUK3TkbpmzvBDWsc0r?= =?us-ascii?Q?HACTZqXIfYkjleYLGFgHSMMpRYGzOGlrBcax9bwIHd/SfjvGhIk2qDfWhlzD?= =?us-ascii?Q?sgCaXrv+4sdQe8KmkBG+sn+LCWnr6e82Ofcwn1JkMEteYCaM95WMk9ARHQAG?= =?us-ascii?Q?yzPz+1FSS317Vyh3nrulpcsITZHZDfbLxbhCShl8?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: e0d297d6-f0ff-4a75-8aa8-08dd2fc054d6 X-MS-Exchange-CrossTenant-AuthSource: CY5PR12MB6405.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 08 Jan 2025 08:42:06.0955 (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: 0hADK82jycXSY+uso3AJR23pBqU7TIh53VpViaCn19hNG9/GPlRlTYlF37r/zCOCARySaoLMs6OnkD1k7rerzA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: LV3PR12MB9144 On Wed, Jan 08, 2025 at 05:33:07PM +0900, Changwoo Min wrote: > scx_ops_bypass() iterates all CPUs to re-enqueue all the scx tasks. > For each CPU, it acquires a lock using rq_lock() regardless of whether > a CPU is offline or the CPU is currently running a task in a higher > scheduler class (e.g., deadline). The rq_lock() is supposed to be used > for online CPUs, and the use of rq_lock() may trigger an unnecessary > warning in rq_pin_lock(). Therefore, replace rq_lock() to > raw_spin_rq_lock() in scx_ops_bypass(). > > This change fixes: 0e7ffff1b811 ("scx: Fix raciness in scx_ops_bypass()") We should use the `Fixes:` tag, put this right before your SoB line: Fixes: 0e7ffff1b811 ("scx: Fix raciness in scx_ops_bypass()") > > Without this change, we observe the following warnings: Maybe report only the first warning, or even something small like this should be sufficient to identify the issue I think: [ 6.615205] rq->balance_callback && rq->balance_callback != &balance_push_callback [ 6.615208] WARNING: CPU: 2 PID: 0 at kernel/sched/sched.h:1730 __schedule+0x1130/0x1c90 Thanks, -Andrea