Merge tag 'sched_ext-for-7.0-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext

Pull sched_ext fixes from Tejun Heo:

 - Fix starvation of scx_enable() under fair-class saturation by
   offloading the enable path to an RT kthread

 - Fix out-of-bounds access in idle mask initialization on systems with
   non-contiguous NUMA node IDs

 - Fix a preemption window during scheduler exit and a refcount
   underflow in cgroup init error path

 - Fix SCX_EFLAG_INITIALIZED being a no-op flag

 - Add READ_ONCE() annotations for KCSAN-clean lockless accesses and
   replace naked scx_root dereferences with container_of() in kobject
   callbacks

 - Tooling and selftest fixes: compilation issues with clang 17,
   strtoul() misuse, unused options cleanup, and Kconfig sync

* tag 'sched_ext-for-7.0-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext:
  sched_ext: Fix starvation of scx_enable() under fair-class saturation
  sched_ext: Remove redundant css_put() in scx_cgroup_init()
  selftests/sched_ext: Fix peek_dsq.bpf.c compile error for clang 17
  selftests/sched_ext: Add -fms-extensions to bpf build flags
  tools/sched_ext: Add -fms-extensions to bpf build flags
  sched_ext: Use READ_ONCE() for plain reads of scx_watchdog_timeout
  sched_ext: Replace naked scx_root dereferences in kobject callbacks
  sched_ext: Use READ_ONCE() for the read side of dsq->nr update
  tools/sched_ext: fix strtoul() misuse in scx_hotplug_seq()
  sched_ext: Fix SCX_EFLAG_INITIALIZED being a no-op flag
  sched_ext: Fix out-of-bounds access in scx_idle_init_masks()
  sched_ext: Disable preemption between scx_claim_exit() and kicking helper work
  tools/sched_ext: Add Kconfig to sync with upstream
  tools/sched_ext: Sync README.md Kconfig with upstream scx
  selftests/sched_ext: Remove duplicated unistd.h include in rt_stall.c
  tools/sched_ext: scx_sdt: Remove unused '-f' option
  tools/sched_ext: scx_central: Remove unused '-p' option
  selftests/sched_ext: Fix unused-result warning for read()
  selftests/sched_ext: Abort test loop on signal