Re: RPI3 sd lockups?

[Greg Troxel <gdt%lexort.com@localhost>]

Brad Spencer <brad%anduin.eldar.org@localhost> writes:

> Can you break into ddb and see if there are a lot of processes hung up??

ddb is not explained at

http://wiki.netbsd.org/ports/evbarm/raspberry_pi/

but I suppose the man page says break on serial console, and also
I see that hw.cnmagic = \x27\x01 which I interpret as a ' followed by
^A.  Is this known to work?

Perhaps related, perhaps not, when I boot up the RPI3 with a FTDI friend
on the headers connected to netbsd-8 with kermit, I see ROM and kernel
output, but can't type.  My .kermrc is

  set carrier-watch off
  set flow-control none
  set parity none
  set line /dev/dtyU0
  set baud 115200

so I woneder if I am doing somthing else wrong.

> I have a RPI2 that doesn't like to have more than 1 device on its I2C
> bus, it turns out, and if one of the devices hangs on read eventually
> the system will hang up completely, probably due to filling up memory
> and/or the process table (one of the devices is read every minute).  I
> noted complaints much like you mention, where it could not write to the
> SD card if I let it go on long enough in this situation.  This is with
> NetBSD 9.x.

This box has no i2x devices or known activity.  It seems to me that
failure to write to the sd controller leads to multiple weewx processes
spinning on cpu and eventual trouble.  But I think the first symptom is
the no writing.