[PATCH 0/2] sched: Fix SCHED_FLAG_KEEP_PARAMS side effects

[Andrea Righi]

SCHED_FLAG_KEEP_PARAMS allows sched_setattr() to update generic task
attributes while retaining the task's existing scheduling parameters and
class.

Two paths in __sched_setscheduler() still act on the requested policy
before the guarded parameter update. One marks the operation as a class
change and invokes class transition callbacks even though the class remains
unchanged. The other performs deadline admission control and can account
bandwidth for a non-deadline task that never enters the deadline class.

Prevent both side effects when SCHED_FLAG_KEEP_PARAMS is set.

Andrea Righi (2):
      sched: Skip class callbacks with SCHED_FLAG_KEEP_PARAMS
      sched/deadline: Skip bandwidth accounting with SCHED_FLAG_KEEP_PARAMS

 kernel/sched/syscalls.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

base-commit: bafb78898eb70fcaa979608a2d7ae9bad86124a1