Re: leds-gpio on x86

[Vincent Pelletier <plr.vincent@gmail.com>]

Hello,

I did a first pass on gpio-f7188x module, and pushed several commits in
my current working branch:

https://github.com/vpelletier/linux/commits/ts651

This commit contains the relevant part of my changes:
  gpio: gpio-f7188x: Use mutex for access serialisation.
(currently:
  https://github.com/vpelletier/linux/commit/0fecf37bcee67d577f7e1e8e58afc463f452bcff
)
but "of course", it does not work: kernel Oops as soon as I trigger the
concurrent access which caused the original issue. With a single active
core, it works fine of course.

Sadly, the traceback is longer than on-screen info, despite being at
1920x1080 resolution with default console font. I recall reading about
a project to display kernel errors as qr-codes, did it get somewhere ?
Also, watchdog kicks in a few seconds after, complaining about hard
lock on (at least) one core, and scrolling even more. I suspect both
cores are hard locked, and have so far no idea what I did wrong:
- each acquire is followed by a release, with no code path around it
- gpio_device.can_sleep is true (as was the case before my patch)

...would I have somehow poked at another bug ?

Regards,
-- 
Vincent Pelletier