Re: [PATCH v4 08/26] sched/deadline: Take a deadline boost from the waiter's rt_mutex node

[Mathieu Desnoyers]

On 2026-11-06 21:25, sashiko-bot@xxxxxxxxxx wrote:
> missing reset of dl_boosted in __sched_setscheduler()

For sysrq-n, this is the same bug as on patch 4, after this patch. The
v5 fix of patch 4 clears dl_boosted here.

For a boosted task that asks for SCHED_DEADLINE itself, this is older
than the series. In the base, pi_se keeps pointing to the donor in the
same case. __setscheduler_dl_pi() only acts for a policy other than
SCHED_DEADLINE. The patch keeps that behaviour, with a copy. The boost
ends at the unlock, where rt_mutex_setprio() clears it. Deciding it
again at sched_setattr() would need the task's new absolute deadline,
which only the next enqueue sets. That is a separate change.

Thanks,

Mathieu

--
Mathieu Desnoyers
EfficiOS Inc.
https://www.efficios.com