Re: Tiny Core v17.0 upgrade issues

[Stefann]

Short update (otherwise this ends rather vague)

It ran until last Saturday, june 20 after which I manually stopped it for unrelated reasons. So it did run without crash for 11 days.

Configuration:
- self compiled TC17.0 kernel with included usb-serial and ftdi single port driver (so,.. NOT the full directory)
- using blocking read and select funtions.

I now basically “give up” on finding deepest rootcause. Variation over testcases and lack of logging makes it kind of undoable.
I will again test the published package once TC17.1 beta gets released.

I brought my application to “non-blocking read” and slowly bring all functionality back in the main home utimation computer (during the troubleshooting had my Solaredge energy, battery and PV on the secondary computer to avoid damage from crashes).

Unless this crashes again there will not be followup on this thread until TC17.1

Thanks to all who helped.

[Stefann]

short update.

I'm running TC17.1 beta since Saturday 9:30. It's now running 48hrs without crash
- vmlinuz, modules.gz and roots.gz from TC download area
- usb-serial-6.18.35-tinycore.tcz
- application configured for blocking reads protected by select()
   (recap: nonblocking reads were not crashing on TC17.0)

So.. fingers crossed. I keep it running.

Note: I will post final results also on TC17.1 thread but did not want to pollute it with intermediate updates.

[Stefann]

well....

TC17.1 has been running fort 7 days (168 hrs) now without crash
- vmlinuz, modules.gz and roots.gz from TC download area
- usb-serial-6.18.35-tinycore.tcz
- application configured for blocking reads from serial port protected by select()
  (recap: nonblocking reads were not crashing on TC17.0)

I would say I can declare this issue solved.

I just restarted the application to bring the serial read to "non-blocking". This should even further enhance the stability.

Anyway... unless it crashes again this thread will no longer get updates

Thanks to all who helped. Significantly @Rich. I largely appreciate your keen eye for detail.

[Stefann]

Well….
5 weeks later and an other crash.
Still running the same TC17.1 beta.
Running with nonblocking serial read. So, although non-blocking read fails less than blocking read protected by select(), it still fails.
And also… as the crashing is very sparse, it could be non-serial read related as well.

Anyway
I gave up on finding the Linux rootcause. Now Just concentrate on finding application workaround.
In stead of using the serial port I can get the same date from an http call. I already tested that and it works. So maybe I will walk that path.

[Stefann]

For those still interested,
As I said, I gave up on finding the linux error.
With that said, as the kernel stalls, I definitely consider this a linux error.
If the application does something naughty it would be normal that the application would crash. The OS however should not.

On application side, I made things more robust.
I close and re-open the serial connection if the data package is not read in N attempts.
I close and re-open the serial connection after each successful data package in stead of listening for ever.
I close and re-open the serial connection if I read unexpected characters.

no idea whether it helps. I guess I will have to wait multiple month.