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60565144df0a ("init: only move down lockup_detector_init() when sdei_watchdog is enabled")
is to fix a 'BUG'. While on ARM64, armv8_pmu_driver_init() is called in do_basic_setup(), it will
fail to create perf event if lockup_detector_init() is moved back. So revert the patch firstly.

Then let's fix the original issue.
When enabling CONFIG_DEBUG_PREEMPT and CONFIG_PREEMPT, it triggers a 'BUG'
in the pmu based nmi_watchdog initializaion:

[ 3.341853] BUG: using smp_processor_id() in preemptible [00000000] code: swapper/0/1
[ 3.344392] caller is debug_smp_processor_id+0x17/0x20
[ 3.344395] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.10.0+ #398
[ 3.344397] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.10.2-0-g5f4c7b1-prebuilt.qemu-project.org 04/01/2014
[ 3.344399] Call Trace:
[ 3.344410] dump_stack+0x60/0x76
[ 3.344412] check_preemption_disabled+0xba/0xc0
[ 3.344415] debug_smp_processor_id+0x17/0x20
[ 3.344422] hardlockup_detector_event_create+0xf/0x60
[ 3.344427] hardlockup_detector_perf_init+0xf/0x41
[ 3.344430] watchdog_nmi_probe+0xe/0x10
[ 3.344432] lockup_detector_init+0x22/0x5b
[ 3.344437] kernel_init_freeable+0x20c/0x245
[ 3.344439] ? rest_init+0xd0/0xd0
[ 3.344441] kernel_init+0xe/0x110
[ 3.344446] ret_from_fork+0x22/0x30

This issue was introduced by commit a79050434b45, which move down
lockup_detector_init() after do_basic_setup(), after sched_init_smp() too.

  hardlockup_detector_event_create
    |- hardlockup_detector_perf_init	(unsafe)
      |- watchdog_nmi_probe
        |- lockup_detector_init
    |- hardlockup_detector_perf_enable
      |- watchdog_nmi_enable
        |- watchdog_enable
          |- lockup_detector_online_cpu
          |- softlockup_start_fn
            |- softlockup_start_all
              |- lockup_detector_reconfigure
                |- lockup_detector_setup
                  |- lockup_detector_init

After analysing the calling context, it's only unsafe to use
smp_processor_id() in hardlockup_detector_perf_init() as the thread
'kernel_init' is preemptible after sched_init_smp().

While it is just a test if we can enable the pmu based nmi_watchdog, the
real enabling process is in softlockup_start_fn() later which ensures
that watchdog_enable() is called on all cores. So it's free to disable
preempt to fix this 'BUG'.

#I3J87Y:【OLK-5.10/openEuler-1.0-LTS】【arm64】内核启动出现BUG: using smp_processor_id() in preemptible