[SOLVED] Crashing/freezing Raspberry Pi when trying to connect to input pin

[adamreisnz]

Have you had any other reports of this? Everything used to work fine until recently, but now whenever I try to connect to an input pin, the Raspberry Pi outright crashes/freezes and I have to manually reboot it.

This is with rpio version 0.9.22, tested with Node 8.9.4, 8.10.0 as well as 8.11.3. Installed on a fresh install of Stretch lite, the last image of April 2018. Full apt-get upgrade.

Any idea's what could be happening? Any underlying packages that may have been updated and are causing failures with rpio?

[adamreisnz]

After some further analysis, I've managed to create a test script that reproduces the issue. However, the problem is that it doesn't reproduce it consistently.

const rpio = require('rpio');
const {INPUT, OUTPUT, HIGH, LOW, PULL_UP} = rpio;
const pin = 29;

console.log('Opening pin');
rpio.open(pin, INPUT, PULL_UP);
console.log('Pin opened');

console.log('Setting up polling');
rpio.poll(pin, pin => {
  console.log('In poll cycle');
  console.log('Reading state');
  const state = rpio.read(pin) || LOW
  console.log(`Pin state is ${state}`);
});

As soon as it hits the line with rpio.poll it crashes. The last console output is Setting up polling.

[adamreisnz]

I've also tried with different pin numbers, and with calling the poll function after a timeout, all to no avail.

[adamreisnz]

After running a few more tests, it appears the culprit is the pull up statement. After removing this, the device no longer seems to crash when reading/polling pin input.

It appears this issue is related https://github.com/raspberrypi/linux/issues/2550

[ASwingler]

I've been battling lockups for the past couple of months. I think it's the same issue you've reported - it started happening after a kernel update (sorry - I didn't record the kernel version). This code consistently (but not always) causes a crash:

var rpio = require('rpio');

var led = 17;
var btn = 2;

rpio.init({mapping: 'gpio'});
rpio.open(btn, rpio.INPUT, rpio.PULL_UP);
rpio.open(led, rpio.OUTPUT, rpio.HIGH);
rpio.poll(btn, pollcb);

function pollcb(pin)
{
        var state = rpio.read(pin) ? 'released' : 'pressed' ;
        rpio.write(led,rpio.read(pin));

}

I've tested this on 3B and 3B+ hardware with the same result.

I noticed a few things:

1. If I run this code and then keeping pushing the button fast at the same time as repeatedly pressing the "enter" key on the console keyboard I can get it to happen.
2. The problem tends to manifest the first time I run node after a boot. If I stop and restart node I don't tend to see it.
3. If I use a different library (inout) I don't see this behavior. This isn't a solution for me however since other libraries don't have the functionality of rpio.
4. The OS does appear to keep running (top -id 0.25 shows ongoing activity). I appear to lose USB and network access however.
5. Prior to the kernel update (sometime in March I think) the code was running fine and was stable.
6. The problem appears whether I use /dev/gpiomem or /dev/mem* This behavior exists on multiple devices. I've used multiple SDCards and built clean from the latest Stretch Lite and the behavior is consistent. I see the problem on node 9.5 and 10.3.

Until your post today I wasn't aware that anyone else was having this problem, but it's a huge issue for me.

Andrew.

[adamreisnz]

Yep, sounds like the same thing with the same symptoms, in particular number 2.

I'm creating a new image now as we speak using an older kernel version (4.9, from http://downloads.raspberrypi.org/raspbian_lite/images/raspbian_lite-2018-03-14/) and once I have that up and running I will report back.

[ASwingler]

Great. Let me know if you need me to test anything.

[adamreisnz]

I can confirm that everything works as expected on 4.9. So the culprit was definitely the linked issue with the 4.14 kernel. Will close this one.

[shiny]

same problem, my script:

const rpio = require('rpio');

const pin = 11;
rpio.open(pin, rpio.INPUT);

rpio.poll(pin, (pin) => {
  console.log('Button event on pin %d, is now %d', pin, rpio.read(pin));
});

My kernel is 4.14.34-v7+.

By the way, this python script works well:

import RPi.GPIO as GPIO
import time
GPIO.setmode(GPIO.BOARD)
channel = 11
GPIO.setup(channel, GPIO.IN, pull_up_down=GPIO.PUD_UP)
cur = False
while True:
    tmp = GPIO.input(channel)
    if tmp == cur:
        time.sleep(0.05)
    else:
        print tmp
        cur = tmp

[adamreisnz]

Did you check https://github.com/raspberrypi/linux/issues/2550?

[zoolyka]

It still hangs with the recent (4.19.x) kernel. Any idea what causes it? So I can submit a ticket to raspbian developers. The latest working version is 4.9.80 (can install it with: sudo rpi-update 5c80565c5c0c7f820258c792a98b56f22db2dd03 - just as a note).

[jperkin]

Did you enable dtoverlay=gpio-no-irq?

[zoolyka]

Can confirm that dtoverlay=gpio-no-irq solves the hangups with recent kernels, thanks a lot!