While running ftrace tests on arm64 hikey device running stable rc 5.4 the following kernel crash reported and these rcu messages are continuously popping up on the console.

Please investigate this problem.

[ 496.652862] rcu: INFO: rcu_preempt self-detected stall on CPU [ 496.815767] rcu: 0-....: (16847 ticks this GP) idle=b7e/1/0x4000000000000004 softirq=11948/11950 fqs=2550 [ 496.986688] (t=6573 jiffies g=53629 q=35) [ 497.146697] Task dump for CPU 0: [ 497.304989] ftracetest R running task 0 3900 1 0x00000223 [ 497.468447] Call trace: [ 497.624270] dump_backtrace+0x0/0x188 [ 497.782003] show_stack+0x24/0x30 [ 497.939405] sched_show_task+0x174/0x208 [ 498.097373] dump_cpu_task+0x48/0x1d0 [ 498.254538] rcu_dump_cpu_stacks+0xac/0xec [ 498.411910] rcu_sched_clock_irq+0xacc/0xea8 [ 498.569587] update_process_times+0x34/0x58 [ 498.727616] tick_sched_handle.isra.15+0x44/0x68 [ 498.886560] tick_sched_timer+0x50/0xa0 [ 499.043913] __hrtimer_run_queues+0x18c/0x618 [ 499.201326] hrtimer_interrupt+0xd8/0x250 [ 499.358101] arch_timer_handler_phys+0x38/0x58 [ 499.515580] handle_percpu_devid_irq+0xd0/0x468 [ 499.673533] generic_handle_irq+0x34/0x50 [ 499.831242] __handle_domain_irq+0x68/0xc0 [ 499.988601] gic_handle_irq+0x60/0xb0 [ 500.145137] el1_irq+0xbc/0x180 [ 500.300334] __do_softirq+0xd4/0x578 [ 500.456294] irq_exit+0x144/0x150 [ 500.611879] __handle_domain_irq+0x6c/0xc0 [ 500.768605] gic_handle_irq+0x60/0xb0 [ 500.924566] el1_irq+0xbc/0x180 [ 501.079125] trace_graph_return+0x120/0x158 [ 501.234796] ftrace_return_to_handler+0x8c/0x140 [ 501.391456] return_to_handler+0x1c/0x38 [ 501.547298] __might_sleep+0x54/0x90 [ 501.702724] __mutex_lock+0x64/0x978 [ 501.857999] mutex_lock_nested+0x3c/0x50 [ 502.012950] tracing_start_cmdline_record+0x10/0x18 [ 502.169084] graph_trace_init+0x3c/0x60 [ 502.324079] tracing_set_tracer+0xfc/0x258 [ 502.479436] tracing_set_trace_write+0x138/0x198 [ 502.636085] __vfs_write+0x48/0x80 [ 502.790455] vfs_write+0xb8/0x1e8 [ 502.944212] ksys_write+0x74/0xf8 [ 503.097397] __arm64_sys_write+0x24/0x30 [ 503.250739] el0_svc_common.constprop.2+0x7c/0x180 [ 503.404489] el0_svc_handler+0x34/0xa0 [ 503.556565] el0_svc+0x8/0xc

metadata: git branch: linux-5.4.y git repo: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git git commit: 14bb11f6495febf1ba14babcf03935cc83827808 git describe: v5.4.27-103-g14bb11f6495f make_kernelversion: 5.4.28-rc1 kernel-config: http://snapshots.linaro.org/openembedded/lkft/lkft/sumo/hikey/lkft/linux-sta... kernel-defconfig: http://snapshots.linaro.org/openembedded/lkft/lkft/sumo/hikey/lkft/linux-sta... build-url: https://ci.linaro.org/job/openembedded-lkft-linux-stable-rc-5.4/DISTRO=lkft,... build-location: http://snapshots.linaro.org/openembedded/lkft/lkft/sumo/hikey/lkft/linux-sta...

ref: https://lkft.validation.linaro.org/scheduler/job/1311185#L12993