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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: f9IZpgxFLne9JJyORrYRQ6uYB1ut1hDw3AR56kbUUSFQI5bYjbSdNvxhgsEFngSocvPEA5udGsb63afNQ5692CJavgYfWEKX6nI8b04dAknzYWuPBv1vlkroWKYqMRUH1qGc6enMbhE37EAYbl2iw9EsXuv9ZVn7DE9zsV7aUXvUPGZ39pYK24XhIoz6n+uik+z9p4CFv3uXbnJf8kSA5mBwc175nvDsIfNh3LzeIN/c8qRjor9/uP2GdAll25YnZESU+oj9oOb87QL086q2O6gISw5p+qOSh0hskq42uV9bFp/ibmrRFrd7R/ptzUrFsQz1UbeM/Mdl5jj9U0IK86CpZ7Arah/yP+S8Kn0NIY4C356HAtBaOaqQx+TPFAqnOhSRNlFTI1Wve2ALTgX5MkbvZ483uBMwrKxwdH5gilJ8LewEMu7qw26lSsnhZX49 X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 09 Feb 2026 04:13:46.3725 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 19c26ba7-8015-4cf8-ad6e-08de67919ec8 X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[satlexmb08.amd.com] X-MS-Exchange-CrossTenant-AuthSource: MWH0EPF000971E5.namprd02.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR12MB4297 Hello Pierre, On 2/5/2026 8:38 PM, Pierre Gondois wrote: > (struct sg_lb_stats).idle_cpus is of type 'unsigned int'. > (local->idle_cpus - busiest->idle_cpus) can underflow to UINT_MAX > for instance, and max_t(long, 0, UINT_MAX) will output UINT_MAX. > > Use lsub_positive() instead of max_t(). > > Fixes: 16b0a7a1a0af ("sched/fair: Ensure tasks spreading in LLC during LB") Should this be commit 0b0695f2b34a ("sched/fair: Rework load_balance()") since I could spot the max_t usage all the way back to to it? Apart from that, feel free to include: Reviewed-by: K Prateek Nayak > cc: stable@vger.kernel.org > Signed-off-by: Pierre Gondois > Reviewed-by: Vincent Guittot > --- > kernel/sched/fair.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c > index da46c31645378..aa14a9982b9f1 100644 > --- a/kernel/sched/fair.c > +++ b/kernel/sched/fair.c > @@ -11249,8 +11249,8 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s > * idle CPUs. > */ > env->migration_type = migrate_task; > - env->imbalance = max_t(long, 0, > - (local->idle_cpus - busiest->idle_cpus)); > + env->imbalance = local->idle_cpus; > + lsub_positive(&env->imbalance, busiest->idle_cpus); > } > > #ifdef CONFIG_NUMA -- Thanks and Regards, Prateek