[GIT PULL] sched_ext: Fixes for v7.4-rc2

[GIT PULL] sched_ext: Fixes for v7.4-rc2

[Tejun Heo]

Hello,

The following changes since commit 4dd16e31135ea8437a720222df34e8745f385d6d:

  Merge tag 'net-7.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net (2026-10-29 08:17:05 -1000)

are available in the Git repository at:

  https://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext.git tags/sched_ext-for-7.4-rc2-fixes

for you to fetch changes up to 700a332c3fe33014bbd5ae852d71ba679fc29e0a:

  sched_ext: Reject DSQ iterator kfuncs in tracing programs (2026-11-12 07:30:07 -1000)

----------------------------------------------------------------
sched_ext: Fixes for v7.4-rc2

- With proxy execution or core scheduling, a CPU could run a task that had
  been requeued on another CPU while dispatch had the rq lock dropped.

- Unregistering a scheduler could return while its teardown was still
  running, letting the teardown call into BPF code that was already freed.

- A CPU coming online could call into the BPF scheduler before the scheduler
  was told that the CPU is online.

- A parent scheduler could be asked to attach a sub-scheduler to a cgroup
  that was already removed.

- Hardening: more kfuncs that take a queue lock are rejected in tracing
  programs, where they could deadlock the CPU, and a queue iterator no
  longer restarts after reaching the end, which the BPF verifier assumes
  can't happen.

- Smaller fixes: tasks needlessly sent back to the BPF scheduler on idle
  CPUs, stale scheduling state carried into a task's next scheduler, and
  uneven CPU shards with partially populated SMT cores.

The branch merged mainline once, for a BPF dependency of a tools/sched_ext
header sync that is yet to be applied.

----------------------------------------------------------------
Andrea Righi (1):
      sched_ext: Avoid unnecessary IMMED reenqueues on idle CPUs

Kang Chen (1):
      sched_ext: make DSQ iterator stay drained after NULL

Kuba Piecuch (1):
      sched_ext: Read exit_kind before flushing in scx_flush_disable_work()

Rahad Bhuiya (1):
      sched_ext: Reset task fields on exit of an SCX_TASK_READY task

Shubhang Kaushik (Ampere) (1):
      sched_ext: Reject scx_bpf_destroy_dsq() in tracing programs

Tao Cui (1):
      sched_ext: Reject DSQ iterator kfuncs in tracing programs

Tejun Heo (6):
      sched_ext: Merge branch 'master' into for-7.4-fixes
      sched_ext: Fix scx_bpf_dsq_reenq() kerneldoc claiming NMI calls are allowed
      sched_ext: Call ops.sub_attach() only while the cgroup is online
      sched_ext: Fix stale pick when the donor changes during dispatch
      sched_ext: Factor out drain_offline_rq()
      sched_ext: Fix ops.enqueue/dispatch() calls before ops.cpu_online()

Zhang Qiao (1):
      sched_ext: Fix partial-SMT core counting in calc_shard_layout()

 kernel/sched/ext/cid.c      |   8 ++-
 kernel/sched/ext/ext.c      | 160 ++++++++++++++++++++++++++++++--------------
 kernel/sched/ext/inlines.h  |  39 +++++++++--
 kernel/sched/ext/internal.h |   4 ++
 kernel/sched/ext/sub.c      |  22 ++++--
 kernel/sched/sched.h        |  17 ++---
 6 files changed, 183 insertions(+), 67 deletions(-)

-- 
tejun