4.10-rc3 rpi issues

[Peter Robinson]

>> > usb is flaky.  raspberry pi 2 b.  Has a edimax wifi dongle, and that
>> > stopped working.  rtl8xxxu driver.  Doesn't find any wifi networks.  usb
>> > keyboard has problems too, looses keys now and then, which makes me
>> > think this is more a usb than a wifi problem.  I had that before, with
>> > the 4.8 kernels.  4.9 works fine.  Now with 4.10-rc3 the problems are
>> > back :(  Anyone seen this too?  Any clues what this might be?
>
>> The Fedora built rc3 kernel seems OK. I'm using usb wifi ATM without
>> too many issues and haven't had any drop outs. I've seen some
>> interesting bits with CMA which I reported [1]. USB doesn't appear at
>> least in my testing to be any worse on the 2 or 3.
>
> Tried to enable some memory debugging, so see if that helps to figure
> what is going on:
>
>     CONFIG_DEBUG_KMEMLEAK=y
>     CONFIG_DEBUG_MEMORY_INIT=y
>     CONFIG_SLUB_DEBUG=y
>     CONFIG_SLUB_DEBUG_ON=y
>
> That made the bug disappear.  :-o
>
> Rawhide kernels are build with quite some debug turned on too, right?
> So that could be it.  Or it is something else:  timing, memory layout /
> alignment, ...

The .0 builds (the first of the new RCs) have debugging disabled and
that's the one I generally run to test the new kernels on various HW
without the perf issues so it shouldn't affect the one I'm using..

Peter