StephenW

The Q5 BSN20 was also missing on my OPi Plus 2 H5 - yet if I boot from the *official* OrangePi ubuntu image the DVFS seemed to work fine. It's a software thing? If I boot with armbian - the board sticks with 1.2Ghz and it would go with random crashes. If I run it under 960Mhz it's stable

OK no problem, understand. I'll keep the clock running at 960mHz... Thank you

Happysax I am trying to contribute also and I just came across in the armbian doc with this: https://docs.armbian.com/Process_Contribute/ I’m still learning, yet see if that would help

After leaving the system running at 960mHz for a couple of days there’re no more sudden reboots. Looks like the H5 does not want to always run at 1152mHz... I inspect the cpu stats and it appears the driver did attempt to step down to 480mhz . From the stat, it looks like the CPU did stepped down, but stepped up again in a very short while under the ondemand governor. And the cpu_cur_freq it’s always reported the top speed (i.e. 960mhz) I notice the H5 CPU freq table is not the same as the stocked Ubuntu image from Sunxi. I can try to patch it but I have to be honest I am quite new to Linux kernel patching and developments. Yet I will try and see if I can modify the dtsi file and rebuild the kernel. the image from orangepi is running in interactive governor, where armbian does not have it. Yet I also notice sunxi have their own CPU freq driver for the H5. the armbian driver is cpufreq-dt. I can try to change the driver and rebuild but I’m not sure if that would make the stepping working. Anyway let me know what I can try and test to get the armbian better with the H5

OK no problem, I understand. Thanks Igor. What I'm trying to do is to lower the CPU clock and see if that would solve the instability problem (I posted in H3 section about using the OPi Zero 2+ with the TFT screen). When I boot with armbian, I see the CPU's keeping at 1152Mhz. When I use the linux image provided by OPi, it's at around 10xx Mhz and it goes up and down. I'm thinking may be the static CPU cycle may have caused the unexpected reboots. I'll let you know the result. So far I put it at 408Mhz, Idle, and so far still running after 10 hours .. i will leave it on for another couple of days.

No, I can't. e.g. if i run "sudo cpufreq-set -r -g performance" there's no change in /etc/default/cpufrequtils. Yet I can change /etc/default/cpufrequtils directly. After reboot, it runs with the desired frequency. But still for ondemand, the CPU speed does not seemed to scale up/down according to the loads.

is it normal? armbian@orangepizeroplus2:~$ sudo armbianmonitor -m Stop monitoring using [ctrl]-[c] Time CPU load %cpu %sys %usr %nice %io %irq CPU C.St. 17:49:19: 1152MHz 0.45 4% 0% 1% 0% 2% 0% 23.2蚓 0/8 17:49:24: 1152MHz 0.42 0% 0% 0% 0% 0% 0% 23.2蚓 0/8 17:49:29: 1152MHz 0.38 0% 0% 0% 0% 0% 0% 23.4蚓 0/8 17:49:34: 1152MHz 0.35 0% 0% 0% 0% 0% 0% 23.5蚓 0/8 17:49:39: 1152MHz 0.32 0% 0% 0% 0% 0% 0% 23.6蚓 0/8 /etc/default/cpufrequtils # WARNING: this file will be replaced on board support package (linux-root-...) upgrade ENABLE=true MIN_SPEED=240000 MAX_SPEED=1200000 GOVERNOR=ondemand

It happens to me that the LED sometimes lit and sometimes do not. I'm not sure what's the cause and for the other boards with H6 CPU I've got... I encounter the same... I can't tell if the board is switched on or not. I just go plugged a USB device in, like a USB network dongle, and when the network light flashes, then I know the board is on or not. And I always plug the UART so I can access the terminal.. this is another way i can tell the device is on or off...

When I tried to debug the insufficient stack space I've found the exception throws at different lines of codes, example below. You can see the exception throws at different times, regardless of the loads. Sometimes it happens few seconds after boot and sometimes it happens after a few hours of idle time. Any ideas? [ 5336.489446] Insufficient stack space to handle exception! [ 5336.489455] ESR: 0x9a000000 -- SP Alignment [ 5336.499040] FAR: 0x0000aaab157f06c0 [ 5336.502541] Task stack: [0xffff000008df8000..0xffff000008dfc000] [ 5336.502543] IRQ stack: [0xffff000008010000..0xffff000008014000] [ 5336.502546] Overflow stack: [0xffff800017f9d0b0..0xffff800017f9e0b0] [ 5336.502556] CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.14.18-sunxi64 #26 [ 5336.502558] Hardware name: Xunlong Orange Pi Zero Plus2 (DT) [ 5336.502561] task: ffff800016969b00 task.stack: ffff000008df8000 [ 5336.502575] PC is at cpu_needs_another_gp+0x5c/0x80 orangepizeroplus2 login: [ 2808.322852] Insufficient stack space to handle exception! [ 2808.322863] ESR: 0x9a000000 -- SP Alignment [ 2808.332442] FAR: 0x0000ffff93b3fd25 [ 2808.335926] Task stack: [0xffff000008df8000..0xffff000008dfc000] [ 2808.342270] IRQ stack: [0xffff000008010000..0xffff000008014000] [ 2808.348614] Overflow stack: [0xffff800017f9d0b0..0xffff800017f9e0b0] [ 2808.354963] CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.14.18-sunxi64 #26 [ 2808.361740] Hardware name: Xunlong Orange Pi Zero Plus2 (DT) [ 2808.367391] task: ffff800016969b00 task.stack: ffff000008df8000 [ 2808.373314] PC is at cpu_needs_another_gp+0x5c/0x80 armbian@orangepizeroplus2:/boot$ [ 3604.982936] Insufficient stack space to handle exception! [ 3604.982946] ESR: 0x9a000000 -- SP Alignment [ 3604.992526] FAR: 0x0000ffffc68c9bb0 [ 3604.996009] Task stack: [0xffff000008df8000..0xffff000008dfc000] [ 3605.002354] IRQ stack: [0xffff000008010000..0xffff000008014000] [ 3605.008698] Overflow stack: [0xffff800017f9d0b0..0xffff800017f9e0b0] [ 3605.015046] CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.14.18-sunxi64 #26 [ 3605.021824] Hardware name: Xunlong Orange Pi Zero Plus2 (DT) [ 3605.027475] task: ffff800016969b00 task.stack: ffff000008df8000 [ 3605.033395] PC is at el1_sync+0x0/0xb0 [ 5.311930] Insufficient stack space to handle exception! [ 5.311938] ESR: 0x9a000000 -- SP Alignment [ 5.321515] FAR: 0x0000ffffb2e7a210 [ 5.324998] Task stack: [0xffff000008df8000..0xffff000008dfc000] [ 5.331342] IRQ stack: [0xffff000008010000..0xffff000008014000] [ 5.337686] Overflow stack: [0xffff800017f9d0b0..0xffff800017f9e0b0] [ 5.344035] CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.14.18-sunxi64 #26 [ 5.350812] Hardware name: Xunlong Orange Pi Zero Plus2 (DT) [ 5.356463] task: ffff800016969b00 task.stack: ffff000008df8000 [ 5.362383] PC is at el1_sync+0x0/0xb0 armbian@orangepizeroplus2:~$ [ 450.420907] Insufficient stack space to handle exception! [ 450.420920] ESR: 0x9a000000 -- SP Alignment [ 450.430498] FAR: 0x0000ffffaec494c8 [ 450.433982] Task stack: [0xffff000008df8000..0xffff000008dfc000] [ 450.440326] IRQ stack: [0xffff000008010000..0xffff000008014000] [ 450.446670] Overflow stack: [0xffff800017f9d0b0..0xffff800017f9e0b0] [ 450.453019] CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.14.18-sunxi64 #26 [ 450.459796] Hardware name: Xunlong Orange Pi Zero Plus2 (DT) [ 450.465449] task: ffff800016969b00 task.stack: ffff000008df8000 [ 450.471370] PC is at invoke_rcu_core+0x0/0x50 armbian@orangepizeroplus2:~$ [27696.023824] Insufficient stack space to handle exception! [27696.023838] ESR: 0x9a000000 -- SP Alignment [27696.033419] FAR: 0x00000000348e1c64 [27696.036902] Task stack: [0xffff000008df8000..0xffff000008dfc000] [27696.043247] IRQ stack: [0xffff000008010000..0xffff000008014000] [27696.049591] Overflow stack: [0xffff800017f9d0b0..0xffff800017f9e0b0] [27696.055941] CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.14.18-sunxi64 #26 [27696.062718] Hardware name: Xunlong Orange Pi Zero Plus2 (DT) [27696.068370] task: ffff800016969b00 task.stack: ffff000008df8000 [27696.074293] PC is at invoke_rcu_core+0x0/0x50 orangepizeroplus2 login: [ 23.856944] Insufficient stack space to handle exception! [ 23.856959] ESR: 0x96000044 -- DABT (current EL) [ 23.866974] FAR: 0x00000000001efef0 [ 23.870457] Task stack: [0xffff000008df8000..0xffff000008dfc000] [ 23.876801] IRQ stack: [0xffff000008010000..0xffff000008014000] [ 23.883146] Overflow stack: [0xffff800017f9d0b0..0xffff800017f9e0b0] [ 23.889495] CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.14.18-sunxi64 #26 [ 23.896272] Hardware name: Xunlong Orange Pi Zero Plus2 (DT) [ 23.901923] task: ffff800016969b00 task.stack: ffff000008df8000 [ 23.907847] PC is at wakeup_softirqd+0x0/0x38 orangepizeroplus2 login: [ 6210.617130] Unable to handle kernel NULL pointer dereference at virtual address 00000008 [ 6210.625227] Mem abort info: [ 6210.628017] Exception class = DABT (current EL), IL = 32 bits [ 6210.633928] SET = 0, FnV = 0 [ 6210.636976] EA = 0, S1PTW = 0 [ 6210.640110] Data abort info: [ 6210.642985] ISV = 0, ISS = 0x00000004 [ 6210.646814] CM = 0, WnR = 0 [ 6210.649778] user pgtable: 4k pages, 48-bit VAs, pgd = ffff800014f60000 [ 6210.656296] [0000000000000008] *pgd=0000000000000000 [ 6210.661257] Internal error: Oops: 96000004 [#1] SMP [ 6210.666128] Modules linked in: snd_soc_hdmi_codec rc_cec dw_hdmi_i2s_audio dw_hdmi_cec cdc_ether usbnet r8152 sun8i_dw_hdmi dw_hdmi cec rc_core spidev sun8i_codec_analog sun4i_gpadc_iio snd_soc_simple_card snd_soc_simple_card_utils snd_soc_core snd_pcm_dmaengine snd_pcm snd_timer sun8i_mixer sun4i_tcon iio_hwmon sun4i_drm industrialio usb_f_acm u_serial g_serial libcomposite brcmfmac brcmutil cfg80211 rfkill sunxi musb_hdrc [ 6210.703673] CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.14.18-sunxi64 #26 [ 6210.710450] Hardware name: Xunlong Orange Pi Zero Plus2 (DT) [ 6210.716100] task: ffff800016969b00 task.stack: ffff000008df8000 [ 6210.722021] PC is at rcu_segcblist_future_gp_needed+0x0/0x48

Thanks I will give it a try. You're right that I'm not intended to show any desktop UI

Igor - After leaving the system running for one night, I've found that the system is still unstable. I'm still experiencing "Insufficient stack space to handle exception" and reboot, even I boost the stack up to 64Mb. I'll have to spend time to trace the map and see which code caused the problem.

I tried to build the armbian on my Orange Pi Zero Plus 2 to work on my astro project. I'm planning to connect the board to the camera module, which I'd assemble with a small scope (120mm focal length), and with a small TFT screen to make it a electronic finder scope. When I build and install the stretch server I've encounter several instability. There were some random crashes and finally I was able to get it stable. I'd like to share it here in case anyone is encountering the same. Here's the info: First I was experiencing random crashes and the exception message shows there's a problem at the high resolution timer. I simply disable the hr timer on the build. That solved the problem. Then I still experiencing random crashes, saying "Insufficient stack space to handle exception". Appearing the default stack of 8Mb was not enough. I make it 16Mb and now it's running stable. Tried running stress for 1 hr and the board is still running fine. So appearing everything is stable now. And I struggle a little bit to make the spidev & tft driver to work with the OrangePi. Here's a very useful guide here: http://eessential.blogspot.hk/2017/12/18-128-x-160-tft-lcd.html?m=1 Description: Debian GNU/Linux 9.3 (stretch) Release: 9.3 Codename: stretch Kernel: 4.14.18