Linux Call Trace

Question

I'm currently facing an issue where in the boot sequence the computer stops booting. This occurs randomly! It always gets stuck on the same place (below). I can't really understand what this is telling me. Anyone have an idea how i might fix this issue? I'm willing to follow instructions to give you guys more information about my issue :)

 [    2.784010] ACPI: Power Button [PWRB]
[    2.787744] input: Power Button as /devices/LNXSYSTM:00/LNXPWRBN:00/input/input2
[    2.795219] ACPI: Power Button [PWRF]
[   23.635987] INFO: rcu_preempt detected stalls on CPUs/tasks:
[   23.641708]  2-...: (2 GPs behind) idle=e14/0/0 softirq=14/14 fqs=0
[   23.648102]  4-...: (5 GPs behind) idle=ac8/0/0 softirq=7/9 fqs=0
[   23.654328]  6-...: (5 GPs behind) idle=8b8/0/0 softirq=9/11 fqs=0
[   23.660641]  7-...: (0 ticks this GP) idle=860/0/0 softirq=18/18 fqs=0
[   23.667758]  (detected by 5, t=21002 jiffies, g=-291, c=-292, q=42)
[   23.674555] Task dump for CPU 2:
[   23.678303] swapper/2       R  running task        0     0      1 0x00200000
[   23.685929]  ffff88046ec91400 ffff88045cb33ed0 ffffffff82092d10 0000000000000001
[   23.693942]  0000000000000000 ffffffff81f262b8 0000000000000000 ffff88045cb34000
[   23.701958]  0000000000000000 0000000000000000 ffff88045cb33ed0 ffffffff810250ff
[   23.709965] Call Trace:
[   23.712956]  [<ffffffff810250ff>] ? arch_cpu_idle+0xf/0x20
[   23.719001]  [<ffffffff810b6c6a>] ? default_idle_call+0x2a/0x30
[   23.725489]  [<ffffffff810b6f1f>] ? cpu_startup_entry+0x2af/0x310
[   23.732132]  [<ffffffff8103b3df>] ? start_secondary+0xef/0x100
[   23.738531] Task dump for CPU 4:
[   23.742307] swapper/4       R  running task        0     0      1 0x00200000
[   23.749988]  ffff88046ed11400 ffff88045cb3bed0 ffffffff82092d10 0000000000000001
[   23.758030]  0000000000000000 ffffffff81f262b8 0000000000000000 ffff88045cb3c000
[   23.766068]  0000000000000000 0000000000000000 ffff88045cb3bed0 ffffffff810250ff
[   23.774102] Call Trace:
[   23.777109]  [<ffffffff810250ff>] ? arch_cpu_idle+0xf/0x20
[   23.783171]  [<ffffffff810b6c6a>] ? default_idle_call+0x2a/0x30
[   23.789681]  [<ffffffff810b6f1f>] ? cpu_startup_entry+0x2af/0x310
[   23.796340]  [<ffffffff8103b3df>] ? start_secondary+0xef/0x100
[   23.802746] Task dump for CPU 6:
[   23.806522] swapper/6       R  running task        0     0      1 0x00200000
[   23.814167]  ffff88046ed91400 ffff88045cb4bed0 ffffffff82092d10 0000000000000001
[   23.822202]  0000000000000000 ffffffff81f262b8 0000000000000000 ffff88045cb4c000
[   23.830244]  0000000000000000 0000000000000000 ffff88045cb4bed0 ffffffff810250ff
[   23.838274] Call Trace:
[   23.841258]  [<ffffffff810250ff>] ? arch_cpu_idle+0xf/0x20
[   23.847297]  [<ffffffff810b6c6a>] ? default_idle_call+0x2a/0x30
[   23.853769]  [<ffffffff810b6f1f>] ? cpu_startup_entry+0x2af/0x310
[   23.860401]  [<ffffffff8103b3df>] ? start_secondary+0xef/0x100
[   23.866753] Task dump for CPU 7:
[   23.870480] swapper/7       R  running task        0     0      1 0x00200000
[   23.878090]  ffff88046edd1400 ffff88045cb4fed0 ffffffff82092d10 0000000000000001
[   23.886097]  0000000000000000 ffffffff81f262b8 0000000000000000 ffff88045cb50000
[   23.894122]  0000000000000000 0000000000000000 ffff88045cb4fed0 ffffffff810250ff
[   23.902135] Call Trace:
[   23.905114]  [<ffffffff810250ff>] ? arch_cpu_idle+0xf/0x20
[   23.911148]  [<ffffffff810b6c6a>] ? default_idle_call+0x2a/0x30
[   23.917607]  [<ffffffff810b6f1f>] ? cpu_startup_entry+0x2af/0x310
[   23.924242]  [<ffffffff8103b3df>] ? start_secondary+0xef/0x100
[   23.930598] rcu_preempt kthread starved for 21002 jiffies! g18446744073709551325 c18446744073709551324 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1
[   23.944112] rcu_preempt     S ffff88045cb13db8     0     7      2 0x00000000
[   23.951741]  ffff88045cb13db8 ffff88046ecceb00 ffff88045ca34c80 ffff88045cb13df0
[   23.959751]  ffff88045cb14000 00000000fffb72e9 ffff88045cb13df0 ffff88046ecceb00
[   23.967771]  0000000000000000 ffff88045cb13dd0 ffffffff819ca1fc ffff88046ecceb00
[   23.975791] Call Trace:
[   23.978770]  [<ffffffff819ca1fc>] schedule+0x3c/0x90
[   23.984298]  [<ffffffff819cd537>] schedule_timeout+0x177/0x330
[   23.990689]  [<ffffffff810d15f0>] ? del_timer_sync+0x50/0x50
[   23.996882]  [<ffffffff810ccdd0>] rcu_gp_kthread+0x5e0/0x900
[   24.003081]  [<ffffffff810cc7f0>] ? synchronize_sched_expedited+0xa0/0xa0
[   24.010415]  [<ffffffff81098239>] kthread+0xc9/0xe0
[   24.015819]  [<ffffffff819ce7cf>] ret_from_fork+0x1f/0x40
[   24.021759]  [<ffffffff81098170>] ? kthread_worker_fn+0x170/0x170

score 0 · Answer 1 · answered Jul 26 '17 at 21:55

The following problems can result in RCU CPU stall warnings:

A CPU-bound real-time task in a CONFIG_PREEMPT kernel, which might happen to preempt a low-priority task in the middle of an RCU read-side critical section. This is especially damaging if that low-priority task is not permitted to run on any other CPU, in which case the next RCU grace period can never complete, which will eventually cause the system to run out of memory and hang.
A CPU-bound real-time task in a CONFIG_PREEMPT_RT kernel that is running at a higher priority than the RCU softirq threads. This will prevent RCU callbacks from ever being invoked, and in a CONFIG_PREEMPT_RCU kernel will further prevent RCU grace periods from ever completing. Either way, the system will eventually run out of memory and hang.

In your case this is happening early in the boot process. Depending on your MOBO/BIOS, there may be a setting to disable or set to auto a feature that will not allow a high priority thread to choke the CPU(s) and cause vital processes to starve while waiting for CPU cycles.

Linux Call Trace

1 Answers1