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[ Upstream commitca125231dd] When a task is migrated out, there is a probability that the tg->load_avg value will become abnormal. The reason is as follows: 1. Due to the 1ms update period limitation in update_tg_load_avg(), there is a possibility that the reduced load_avg is not updated to tg->load_avg when a task migrates out. 2. Even though __update_blocked_fair() traverses the leaf_cfs_rq_list and calls update_tg_load_avg() for cfs_rqs that are not fully decayed, the key function cfs_rq_is_decayed() does not check whether cfs->tg_load_avg_contrib is null. Consequently, in some cases, __update_blocked_fair() removes cfs_rqs whose avg.load_avg has not been updated to tg->load_avg. Add a check of cfs_rq->tg_load_avg_contrib in cfs_rq_is_decayed(), which fixes the case (2.) mentioned above. Fixes:1528c661c2("sched/fair: Ratelimit update to tg->load_avg") Signed-off-by: xupengbo <xupengbo@oppo.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Aaron Lu <ziqianlu@bytedance.com> Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org> Tested-by: Aaron Lu <ziqianlu@bytedance.com> Link: https://patch.msgid.link/20250827022208.14487-1-xupengbo@oppo.com Signed-off-by: Sasha Levin <sashal@kernel.org>