Segfault

[risacher]

I repeatably get a segfault that I think is in i2c, but it takes a few hours for it to happen. During that time, the process size grows slowly, so maybe it's a memory leak issue?

I am using node 0.10.33 and adafruit-i2c-lcd on a raspberry pi B; with i2c module pulled from latest github. The test program scrolls text across the lcd display, changing the text on a 100ms interval.

Unfortunately when the segfault happens, it seems to corrupt the stack, so I haven't been able to get a good backtrace in gdb or core file.

[risacher]

Here's the test program that causes the crash: http://risacher.org/ref/test2-buttons.js

[risacher]

if anyone has tips on how to debug this, I'd much appreciate.

[kelly]

You could try upgrading to the latest version of i2c. It looks like that project depends on 0.1.4, but you shouldn't have any problems upgrading it to 0.1.6.

[risacher]

well, what I actually put in the adafruit-i2c-lcd/package.json dependencies is this:

"i2c": "git://github.com/kelly/node-i2c.git"

But it doesn't help

[risacher]

[edited]The segfault always happens inside ReadBlock().

[risacher]

At src/i2c.cc:133 The SEGV happens on this line: Local

[arskb4ga]

Did this SEGV ever get resolved?

[risacher]

I don't think so. I haven't tested it lately - that project went on indefinite hold. I'll try it tonight.

[risacher]

I upgraded to node 0.12.6; ran npm update, which pulled in i2c v0.2.1. I then ran my test program and let it run all night - no segfault. I forgot to check for process growth. I'm running the test again, but I think the problem is resolved. If it hasn't crashed by tonight, I'll close the issue.

[arskb4ga]

Thanks for your work testing this! I am running Node 10.38 on a PI-2, I have not been able to get the PI to load version Node 12. What platform are you running? I tested with another i2c program and it ran OK, but I used readByte and not readyBytes (block), I would assume it would fail if I used the block mode also until upgrade node, based on my reading.

[risacher]

My pi's (I think I have 3) are RPi 1 Model B. I installed node 0.12.6 via instructions at http://weworkweplay.com/play/raspberry-pi-nodejs/ - basically a installed a package built by heroku.

[arskb4ga]

Thanks, I will take a look at this, it will save me a lot of time if it works.

[arskb4ga]

I have been testing for a while with node 0.12.6 and it seems to be working fine. I don't notice the memory leak that were there with 0.10.38. Strange it was intermittent when it came to how long the process ran before the segfault.

[risacher]

No crash; no leak. Closing.