Re: Lockdep warning when using REGCACHE_RBTREE

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From	Mark Brown <broonie@kernel.org>
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Subject	Re: Lockdep warning when using REGCACHE_RBTREE
Date	Fri, 15 Jan 2016 13:00:02 +0100
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On Fri, Jan 15, 2016 at 10:45:41AM +0100, Peter Zijlstra wrote:

> So _regmap_write() does: map->lock(map->lock_arg)

> Which isn't very enlightening, since that can be a mutex or a spinlock,
> the above strongly suggests spinlock though.

> Looking at __regmap_init(), this seems to depend on:

>   (bus && bus->fast_io) || config->fast_io

> now, afaict, regmap_mmio is used in this case, which has .fast_io =
> true.

> So yeah, fail.

Indeed, that'd do it.  It hadn't occurred to me that someone would be
using MMIO with an rbtree cache.

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Thread

Lockdep warning when using REGCACHE_RBTREE Stefan Agner <stefan@agner.ch> - 2016-01-14 23:40 +0100
  Re: Lockdep warning when using REGCACHE_RBTREE Mark Brown <broonie@kernel.org> - 2016-01-15 01:10 +0100
    Re: Lockdep warning when using REGCACHE_RBTREE Stefan Agner <stefan@agner.ch> - 2016-01-15 02:20 +0100
      Re: Lockdep warning when using REGCACHE_RBTREE Mark Brown <broonie@kernel.org> - 2016-01-15 17:30 +0100
        Re: Lockdep warning when using REGCACHE_RBTREE Stefan Agner <stefan@agner.ch> - 2016-01-15 20:20 +0100
  Re: Lockdep warning when using REGCACHE_RBTREE Peter Zijlstra <peterz@infradead.org> - 2016-01-15 10:50 +0100
    Re: Lockdep warning when using REGCACHE_RBTREE Mark Brown <broonie@kernel.org> - 2016-01-15 13:00 +0100

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