PI hangs or network hangs?

[Fabio72]

Since I started to use raspi with xbian I faced, time to time, the same problem.
Xbian works fine for days or weeks then suddenly, after an AC failure or some other problem, it start freezing after 30 or less minutes of use, with no errors in any log.
Then I restore last backup without solving the problem.
Every single time I have to try many backup restores to get it working again. Usually I have to restore a much older backup.

I switched to nfs root but this issue is always present.

I changed hardware (B and B+, SD card, PSU) with no luck.

My Xbian is up for months, survives firmware and kernel updates and reboots. Then suddenly it starts freezing again. Until I restore a month old backup.

I just read this article
https://raspberrypispot.wordpress.com/2013/07/08/wifi-and-ethernet-dropout-problems-in-raspberry-pi/
“FIQ interrupt not triggering IRQ interrupt causing USB to dropout”
I tried on my system

Terminal

root@xbian /home/xbian/.kodi/temp # cat /sys/devices/platform/bcm2708_usb/regoffset
0xffffffff
root@xbian /home/xbian/.kodi/temp # cat /sys/devices/platform/bcm2708_usb/regvalue
invalid offset

And then

Terminal

root@xbian /home/xbian/.kodi/temp/check_lan # echo 08 > /sys/devices/platform/bcm2708_usb/regoffset
root@xbian /home/xbian/.kodi/temp/check_lan # cat /sys/devices/platform/bcm2708_usb/regvalue
Reg@0x000008 = 0x00000031
root@xbian /home/xbian/.kodi/temp/check_lan # echo 0x31 > /sys/devices/platform/bcm2708_usb/regvalue
root@xbian /home/xbian/.kodi/temp/check_lan # cat /sys/devices/platform/bcm2708_usb/regvalue
Reg@0x000008 = 0x00000031

Maybe this is the problem: network stop answering but raspi is not freezed. Having root nfs, nothing is written to the logs.
Then I remove the power plug to restart the PI and no trace of what happened remains in logs.

Now I'm trying the script in the article

[f1vefour]

Thanks for pointing this out.

[f1vefour]

I don't understand why this is necessary, it seems this should be fixed in the kernel source. Have you submitted an issue on the Raspberry kernel git?

[Fabio72]

I don't know if it's a bug, or if it's the real cause of my system freezes.
And it seems strange to me being the only one affected by this since 2013 (date of the article).
I don't have time to go deeper in FIQ and kernel stuff: I was only looking for a workaround for my system freezes.

What is the content of your
/sys/devices/platform/bcm2708_usb/regoffset
and
/sys/devices/platform/bcm2708_usb/regvalue ?

[CurlyMo]

Code:

root@pi ~ # cat /sys/devices/platform/bcm2708_usb/regoffset
0xffffffff
root@pi ~ # cat /sys/devices/platform/bcm2708_usb/regvalue
invalid offset

[Fabio72]

As was mine, before putting instructions to write right values in rc.local
Now you will see an invalid offset error also in your dmesg

This github issue is closed since long time
https://github.com/raspberrypi/linux/issues/151

I don't know if is still a bug cause I cannot see any error logged when my pi hangs. And I don't known what really happened cause the network is unreachable and usb keyboard is not able to awake xbian from black screen.

I also found this discussion in google groups
https://groups.google.com/forum/#!msg/piwall-users/xvamuVOOaRk/j0VdVws9v9UJ
It seems similar: network freeze whitout errors in log

[Slab]

I think I'm also affected by this problem, check this thread: http://forum.xbian.org/thread-2801-post-27790.html#pid27790

[Fabio72]

I added

Code:

echo 08 > /sys/devices/platform/bcm2708_usb/regoffset
echo 0x31 > /sys/devices/platform/bcm2708_usb/regvalue

in
/etc/rc.local

[Fabio72]

I found two other issues about system freeze during big usb or network transfer

https://github.com/xbianonpi/xbian/issues/666

https://github.com/xbianonpi/xbian/issues/691

[CurlyMo]

Is this in itself already on github somewhere?

[Fabio72]

I think this is the issue about linux kernel
https://github.com/raspberrypi/linux/issues/151