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    Subject[PATCH 0/2] freezer,sched: do not restore saved_state of a thawed task
    Date
    This series applies couple fixes to commit 8f0eed4a78a8 ("freezer,sched:
    Use saved_state to reduce some spurious wakeups") which was found while
    testing with legacy cgroup freezer. My original testing was only with
    system-wide freezer. We found that thaw_task could be called on a task
    which was already frozen. Prior to commit 8f0eed4a78a8 ("freezer,sched:
    Use saved_state to reduce some spurious wakeups"), this wasn't an issue
    as kernel would try to wake up TASK_FROZEN, which wouldn't match the
    thawed task state, and no harm done to task. After commit 8f0eed4a78a8
    ("freezer,sched: Use saved_state to reduce some spurious wakeups"), it
    was possible to overwrite the state of thawed task.

    To: Rafael J. Wysocki <rafael@kernel.org>
    To: Pavel Machek <pavel@ucw.cz>
    To: Ingo Molnar <mingo@kernel.org>
    To: Peter Zijlstra (Intel) <peterz@infradead.org>
    Cc: <linux-arm-msm@vger.kernel.org>
    Cc: Pavan Kondeti <quic_pkondeti@quicinc.com>
    Cc: Aiqun Yu (Maria) <quic_aiquny@quicinc.com>
    Cc: <linux-pm@vger.kernel.org>
    Cc: <linux-kernel@vger.kernel.org>
    Signed-off-by: Elliot Berman <quic_eberman@quicinc.com>

    Originally sent to only linux-arm-msm, resending to correct authors.
    - Link to v1: https://lore.kernel.org/r/20231120-freezer-state-multiple-thaws-v1-0-a4c453f50745@quicinc.com

    ---
    Elliot Berman (2):
    freezer,sched: do not restore saved_state of a thawed task
    freezer,sched: clean saved_state when restoring it during thaw

    kernel/freezer.c | 3 ++-
    1 file changed, 2 insertions(+), 1 deletion(-)
    ---
    base-commit: 6d7e4782bcf549221b4ccfffec2cf4d1a473f1a3
    change-id: 20231108-freezer-state-multiple-thaws-7a3a8d9dadb3

    Best regards,
    --
    Elliot Berman <quic_eberman@quicinc.com>

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