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Re: [PATCH v2 0/4] gpio: fix an incorrect lockdep warning

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2016-09-18 21:43 GMT+02:00 Bartosz Golaszewski <bgolaszewski@baylibre.com>:
> 2016-09-18 10:52 GMT+02:00 Peter Rosin <peda@axentia.se>:
>> On 2016-09-16 19:58, Wolfram Sang wrote:
>>>
>>> Same here. And if it prevents us from false positive lockdep reports, I
>>> am all for fixing it.
>>
>> Except it doesn't, when I think some more about it...
>>
>> If you have two gpio-expanders on the same depth but on different i2c
>> branches you still end up with a splat if one is used to control a mux
>> to reach the other.
>>
>> The only way to solve it for good, that I see, is to have every instance
>> of the gpio-expander mutex in its own class. That might lead to many
>> lockdep classes but then again, how many gpio expanders could there be
>> in a system? A dozen or two seems extreme, so maybe that is the correct
>> approach anyway?
>
> Wouldn't it be enough to have a separate class for every base (as in:
> not having any parent adapters) i2c adapter?
>

Eeek -ESENTTOOEARLY

Of course not - since we could have two branches deeper on the tree
with the same problem.

Nevermind my last e-mail.

Best regards,
Bartosz Golaszewski

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[PATCH v2 0/4] gpio: fix an incorrect lockdep warning Bartosz Golaszewski <bgolaszewski@baylibre.com> - 2016-09-16 18:10 +0200
  [PATCH v2 3/4] i2c: add a warning to i2c_adapter_depth() Bartosz Golaszewski <bgolaszewski@baylibre.com> - 2016-09-16 18:10 +0200
  Re: [PATCH v2 0/4] gpio: fix an incorrect lockdep warning Wolfram Sang <wsa@the-dreams.de> - 2016-09-16 19:30 +0200
    Re: [PATCH v2 0/4] gpio: fix an incorrect lockdep warning Wolfram Sang <wsa@the-dreams.de> - 2016-09-16 20:00 +0200
      Re: [PATCH v2 0/4] gpio: fix an incorrect lockdep warning Bartosz Golaszewski <bgolaszewski@baylibre.com> - 2016-09-18 21:50 +0200
        Re: [PATCH v2 0/4] gpio: fix an incorrect lockdep warning Peter Zijlstra <peterz@infradead.org> - 2016-09-19 10:20 +0200
          Re: [PATCH v2 0/4] gpio: fix an incorrect lockdep warning Peter Zijlstra <peterz@infradead.org> - 2016-09-19 11:10 +0200
            Re: [PATCH v2 0/4] gpio: fix an incorrect lockdep warning Bartosz Golaszewski <bgolaszewski@baylibre.com> - 2016-09-20 12:10 +0200
              Re: [PATCH v2 0/4] gpio: fix an incorrect lockdep warning Peter Zijlstra <peterz@infradead.org> - 2016-09-20 12:30 +0200
              Re: [PATCH v2 0/4] gpio: fix an incorrect lockdep warning Geert Uytterhoeven <geert@linux-m68k.org> - 2016-09-20 13:40 +0200
                Re: [PATCH v2 0/4] gpio: fix an incorrect lockdep warning Bartosz Golaszewski <bgolaszewski@baylibre.com> - 2016-09-20 14:40 +0200
            Re: [PATCH v2 0/4] gpio: fix an incorrect lockdep warning Thomas Gleixner <tglx@linutronix.de> - 2016-09-20 17:40 +0200
      Re: [PATCH v2 0/4] gpio: fix an incorrect lockdep warning Bartosz Golaszewski <bgolaszewski@baylibre.com> - 2016-09-18 21:50 +0200
  Re: [PATCH v2 0/4] gpio: fix an incorrect lockdep warning Peter Zijlstra <peterz@infradead.org> - 2016-09-17 03:30 +0200
    Re: [PATCH v2 0/4] gpio: fix an incorrect lockdep warning Wolfram Sang <wsa@the-dreams.de> - 2016-09-17 12:20 +0200
      Re: [PATCH v2 0/4] gpio: fix an incorrect lockdep warning Bartosz Golaszewski <bgolaszewski@baylibre.com> - 2016-09-17 21:10 +0200

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