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    Subject[PATCH] sched/core: Fix reset-on-fork from RT with uclamp
    From
    uclamp_fork() resets the uclamp values to their default when the
    reset-on-fork flag is set. It also checks whether the task has a RT
    policy, and sets its uclamp.min to 1024 accordingly. However, during
    reset-on-fork, the task's policy is lowered to SCHED_NORMAL right after,
    hence leading to an erroneous uclamp.min setting for the new task if it
    was forked from RT.

    Fix this by removing the unnecessary check on rt_policy() in
    uclamp_fork() as this doesn't make sense if the reset-on-fork flag is
    set.

    Reported-by: Chitti Babu Theegala <ctheegal@codeaurora.org>
    Signed-off-by: Quentin Perret <qperret@google.com>
    ---
    kernel/sched/core.c | 4 ----
    1 file changed, 4 deletions(-)

    diff --git a/kernel/sched/core.c b/kernel/sched/core.c
    index 3a61a3b8eaa9..9ea3e484eea2 100644
    --- a/kernel/sched/core.c
    +++ b/kernel/sched/core.c
    @@ -1234,10 +1234,6 @@ static void uclamp_fork(struct task_struct *p)
    for_each_clamp_id(clamp_id) {
    unsigned int clamp_value = uclamp_none(clamp_id);

    - /* By default, RT tasks always get 100% boost */
    - if (unlikely(rt_task(p) && clamp_id == UCLAMP_MIN))
    - clamp_value = uclamp_none(UCLAMP_MAX);
    -
    uclamp_se_set(&p->uclamp_req[clamp_id], clamp_value, false);
    }
    }
    --
    2.26.0.110.g2183baf09c-goog
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