Steps is same with LIN8-3183, when the test failure is solved with the patch, there will be below info printed when board starts up:
[ 0.152789] [ INFO: suspicious RCU usage. ]
[ 0.152795] 4.1.17-rt13-WR8.0.0.2_preempt-rt #80 Not tainted
[ 0.152797] -------------------------------
[ 0.152804] /RCPL/test4_axm55xx_rt_rcpl1/bitbake_build/tmp/work-shared/axxiaarm/kernel-source/kernel/pid.c:399 suspicious rcu_dereference_check() usage!
[ 0.152806]
other info that might help us debug this:
[ 0.152810]
rcu_scheduler_active = 1, debug_locks = 0
[ 0.152814] 2 locks held by swapper/0/0:
[ 0.152836] #0: (tasklist_lock){+.+...}, at: [<c042bb30>] copy_process.part.5+0xe70/0x174c
[ 0.152852] #1: (init_sighand.siglock){+.+...}, at: [<c042bb88>] copy_process.part.5+0xec8/0x174c
[ 0.152854]
stack backtrace:
[ 0.152860] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.1.17-rt13-WR8.0.0.2_preempt-rt #80
[ 0.152863] Hardware name: LSI Axxia
[ 0.152878] [<c041a594>] (unwind_backtrace) from [<c0414080>] (show_stack+0x20/0x24)
[ 0.152888] [<c0414080>] (show_stack) from [<c0ad5bf4>] (dump_stack+0x78/0x98)
[ 0.152898] [<c0ad5bf4>] (dump_stack) from [<c0479978>] (lockdep_rcu_suspicious+0xd8/0x114)
[ 0.152908] [<c0479978>] (lockdep_rcu_suspicious) from [<c044fa84>] (attach_pid+0x68/0xe4)
[ 0.152918] [<c044fa84>] (attach_pid) from [<c042c01c>] (copy_process.part.5+0x135c/0x174c)
[ 0.152927] [<c042c01c>] (copy_process.part.5) from [<c042c4b4>] (copy_process+0x6c/0x84)
[ 0.152935] [<c042c4b4>] (copy_process) from [<c042c5d8>] (do_fork+0x84/0x7c0)
[ 0.152943] [<c042c5d8>] (do_fork) from [<c042cd4c>] (kernel_thread+0x38/0x40)
[ 0.152953] [<c042cd4c>] (kernel_thread) from [<c0ad1644>] (rest_init+0x30/0x174)
[ 0.152964] [<c0ad1644>] (rest_init) from [<c0d78cf4>] (start_kernel+0x3a4/0x414)
[ 0.152971] [<c0d78cf4>] (start_kernel) from [<0040808c>] (0x40808c)
