Hi,
> Am 19.09.2021 um 19:41 schrieb Jarkko Nikula <jarkko.nikula@xxxxxxxxxx>:
>
> I found another timer related regression on BeagleBoard Rev C2 which was
I remembered that I have a BB C2 collecting dust...
> present before 6cfcd5563b4f ("clocksource/drivers/timer-ti-dm: Fix
> suspend and resume for am3 and am4") and which remains after fix
> 3ff340e24c9d ("bus: ti-sysc: Fix gpt12 system timer issue with reserved
> status") including today's head d4d016caa4b8 ("alpha: move __udiv_qrnnd
> library function to arch/alpha/lib/").
>
> Issue occurs when omap3_isp is not loaded and symptoms are the same than
> my previous finding [1]. I.e. timer interrupts appear missing and need
> to hit keys on serial console in order to let boot (when omap3_isp not
> built) or "sleep 1" in shell to continue.
After removing dust, I can confirm both effects after doing
echo blacklist omap3_isp >/etc/modprobe.d/isp.conf
and rebooting.
Another effect I have seen is that heartbeat (I think it is a local patch
I have in our devicetree) stops and toggles almost each time I press the enter
key on the serial console.
And, I once got attached log.
Hope this helps.
BR and thanks,
Nikolaus
root@letux:~# uname -a
Linux letux 5.15.0-rc2-letux+ #6867 SMP PREEMPT Mon Sep 20 19:47:48 CEST 2021 armv7l GNU/Linux
root@letux:~#
root@letux:~# [ 444.397186] rcu: INFO: rcu_preempt self-detected stall on CPU
[ 444.403594] rcu: 0-...!: (1 ticks this GP) idle=869/1/0x40000002 softirq=7514/7514 fqs=0
[ 444.412689] (t=5297 jiffies g=17433 q=5)
[ 444.417144] rcu: rcu_preempt kthread timer wakeup didn't happen for 5296 jiffies! g17433 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
[ 444.429595] rcu: Possible timer handling issue on cpu=0 timer-softirq=4616
[ 444.437225] rcu: rcu_preempt kthread starved for 5297 jiffies! g17433 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
[ 444.448638] rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
[ 444.458618] rcu: RCU grace-period kthread stack dump:
[ 444.464172] task:rcu_preempt state:I stack: 0 pid: 11 ppid: 2 flags:0x00000000
[ 444.473449] [<c089cd68>] (__schedule) from [<c089cfcc>] (schedule+0xdc/0x12c)
[ 444.481353] [<c089cfcc>] (schedule) from [<c08a006c>] (schedule_timeout+0xc0/0xec)
[ 444.489685] [<c08a006c>] (schedule_timeout) from [<c018e794>] (rcu_gp_fqs_loop+0x108/0x2d4)
[ 444.498901] [<c018e794>] (rcu_gp_fqs_loop) from [<c018f940>] (rcu_gp_kthread+0xf0/0x128)
[ 444.507812] [<c018f940>] (rcu_gp_kthread) from [<c0150878>] (kthread+0x14c/0x154)
[ 444.516082] [<c0150878>] (kthread) from [<c0100150>] (ret_from_fork+0x14/0x24)
[ 444.524047] Exception stack(0xc10dbfb0 to 0xc10dbff8)
[ 444.529632] bfa0: ???????? ???????? ???????? ????????
[ 444.538574] bfc0: ???????? ???????? ???????? ???????? ???????? ???????? ???????? ????????
[ 444.547515] bfe0: ???????? ???????? ???????? ???????? ???????? ????????
[ 444.554779] rcu: Stack dump where RCU GP kthread last ran:
[ 444.560821] NMI backtrace for cpu 0
[ 444.564697] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.15.0-rc2-letux+ #6867
[ 444.572540] Hardware name: Generic OMAP3-GP (Flattened Device Tree)
[ 444.579406] [<c010f1a0>] (unwind_backtrace) from [<c010a47c>] (show_stack+0x10/0x14)
[ 444.587951] [<c010a47c>] (show_stack) from [<c0896148>] (dump_stack_lvl+0x40/0x4c)
[ 444.596313] [<c0896148>] (dump_stack_lvl) from [<c04cc82c>] (nmi_cpu_backtrace+0xd4/0xe8)
[ 444.605316] [<c04cc82c>] (nmi_cpu_backtrace) from [<c04cc8f0>] (nmi_trigger_cpumask_backtrace+0xb0/0x184)
[ 444.615814] [<c04cc8f0>] (nmi_trigger_cpumask_backtrace) from [<c0893c54>] (rcu_check_gp_kthread_starvation+0x118/0x150)
[ 444.627716] [<c0893c54>] (rcu_check_gp_kthread_starvation) from [<c01926e8>] (rcu_sched_clock_irq+0x360/0xae0)
[ 444.638702] [<c01926e8>] (rcu_sched_clock_irq) from [<c019b8f4>] (update_process_times+0x90/0xc4)
[ 444.648468] [<c019b8f4>] (update_process_times) from [<c01ac714>] (tick_sched_handle+0x54/0x60)
[ 444.658020] [<c01ac714>] (tick_sched_handle) from [<c01acb84>] (tick_sched_timer+0x44/0x9c)
[ 444.667205] [<c01acb84>] (tick_sched_timer) from [<c019c520>] (__hrtimer_run_queues+0x17c/0x280)
[ 444.676849] [<c019c520>] (__hrtimer_run_queues) from [<c019d25c>] (hrtimer_interrupt+0xb0/0x208)
[ 444.686492] [<c019d25c>] (hrtimer_interrupt) from [<c0727df8>] (dmtimer_clockevent_interrupt+0x24/0x2c)
[ 444.696807] [<c0727df8>] (dmtimer_clockevent_interrupt) from [<c017ebd4>] (__handle_irq_event_percpu+0xb8/0x200)
[ 444.707977] [<c017ebd4>] (__handle_irq_event_percpu) from [<c017ed40>] (handle_irq_event_percpu+0x24/0x70)
[ 444.718566] [<c017ed40>] (handle_irq_event_percpu) from [<c017edc4>] (handle_irq_event+0x38/0x5c)
[ 444.728302] [<c017edc4>] (handle_irq_event) from [<c0183598>] (handle_level_irq+0x7c/0xb4)
[ 444.737396] [<c0183598>] (handle_level_irq) from [<c017def0>] (handle_irq_desc+0x24/0x34)
[ 444.746398] [<c017def0>] (handle_irq_desc) from [<c017e574>] (handle_domain_irq+0x3c/0x54)
[ 444.755493] [<c017e574>] (handle_domain_irq) from [<c0100b3c>] (__irq_svc+0x5c/0x90)
[ 444.764007] Exception stack(0xc0d01ed0 to 0xc0d01f18)
[ 444.769561] 1ec0: ???????? ???????? ???????? ????????
[ 444.778503] 1ee0: ???????? ???????? ???????? ???????? ???????? ???????? ???????? ????????
[ 444.787445] 1f00: ???????? ???????? ???????? ???????? ???????? ????????
[ 444.794708] [<c0100b3c>] (__irq_svc) from [<c06f64cc>] (cpuidle_enter_state+0x1c4/0x2f8)
[ 444.803619] [<c06f64cc>] (cpuidle_enter_state) from [<c06f6664>] (cpuidle_enter+0x50/0x54)
[ 444.812713] [<c06f6664>] (cpuidle_enter) from [<c01603e4>] (do_idle+0x274/0x2a0)
[ 444.820861] [<c01603e4>] (do_idle) from [<c0160714>] (cpu_startup_entry+0x18/0x1c)
[ 444.829193] [<c0160714>] (cpu_startup_entry) from [<c0c0128c>] (start_kernel+0x770/0x958)
[ 444.838409] NMI backtrace for cpu 0
[ 444.842285] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.15.0-rc2-letux+ #6867
[ 444.850128] Hardware name: Generic OMAP3-GP (Flattened Device Tree)
[ 444.857025] [<c010f1a0>] (unwind_backtrace) from [<c010a47c>] (show_stack+0x10/0x14)
[ 444.865570] [<c010a47c>] (show_stack) from [<c0896148>] (dump_stack_lvl+0x40/0x4c)
[ 444.873901] [<c0896148>] (dump_stack_lvl) from [<c04cc82c>] (nmi_cpu_backtrace+0xd4/0xe8)
[ 444.882904] [<c04cc82c>] (nmi_cpu_backtrace) from [<c04cc8f0>] (nmi_trigger_cpumask_backtrace+0xb0/0x184)
[ 444.893402] [<c04cc8f0>] (nmi_trigger_cpumask_backtrace) from [<c0893dac>] (rcu_dump_cpu_stacks+0x120/0x144)
[ 444.904174] [<c0893dac>] (rcu_dump_cpu_stacks) from [<c01926ec>] (rcu_sched_clock_irq+0x364/0xae0)
[ 444.914001] [<c01926ec>] (rcu_sched_clock_irq) from [<c019b8f4>] (update_process_times+0x90/0xc4)
[ 444.923736] [<c019b8f4>] (update_process_times) from [<c01ac714>] (tick_sched_handle+0x54/0x60)
[ 444.933288] [<c01ac714>] (tick_sched_handle) from [<c01acb84>] (tick_sched_timer+0x44/0x9c)
[ 444.942443] [<c01acb84>] (tick_sched_timer) from [<c019c520>] (__hrtimer_run_queues+0x17c/0x280)
[ 444.952087] [<c019c520>] (__hrtimer_run_queues) from [<c019d25c>] (hrtimer_interrupt+0xb0/0x208)
[ 444.961730] [<c019d25c>] (hrtimer_interrupt) from [<c0727df8>] (dmtimer_clockevent_interrupt+0x24/0x2c)
[ 444.972045] [<c0727df8>] (dmtimer_clockevent_interrupt) from [<c017ebd4>] (__handle_irq_event_percpu+0xb8/0x200)
[ 444.983215] [<c017ebd4>] (__handle_irq_event_percpu) from [<c017ed40>] (handle_irq_event_percpu+0x24/0x70)
[ 444.993804] [<c017ed40>] (handle_irq_event_percpu) from [<c017edc4>] (handle_irq_event+0x38/0x5c)
[ 445.003540] [<c017edc4>] (handle_irq_event) from [<c0183598>] (handle_level_irq+0x7c/0xb4)
[ 445.012634] [<c0183598>] (handle_level_irq) from [<c017def0>] (handle_irq_desc+0x24/0x34)
[ 445.021636] [<c017def0>] (handle_irq_desc) from [<c017e574>] (handle_domain_irq+0x3c/0x54)
[ 445.030700] [<c017e574>] (handle_domain_irq) from [<c0100b3c>] (__irq_svc+0x5c/0x90)
[ 445.039215] Exception stack(0xc0d01ed0 to 0xc0d01f18)
[ 445.044799] 1ec0: ???????? ???????? ???????? ????????
[ 445.053741] 1ee0: ???????? ???????? ???????? ???????? ???????? ???????? ???????? ????????
[ 445.062683] 1f00: ???????? ???????? ???????? ???????? ???????? ????????
[ 445.069946] [<c0100b3c>] (__irq_svc) from [<c06f64cc>] (cpuidle_enter_state+0x1c4/0x2f8)
[ 445.078857] [<c06f64cc>] (cpuidle_enter_state) from [<c06f6664>] (cpuidle_enter+0x50/0x54)
[ 445.087951] [<c06f6664>] (cpuidle_enter) from [<c01603e4>] (do_idle+0x274/0x2a0)
[ 445.096099] [<c01603e4>] (do_idle) from [<c0160714>] (cpu_startup_entry+0x18/0x1c)
[ 445.104431] [<c0160714>] (cpu_startup_entry) from [<c0c0128c>] (start_kernel+0x770/0x958)
root@letux:~#
