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Date: Sat, 1 Aug 2015 13:21:09 +0200 (CEST)
From: Julia Lawall <julia.lawall@lip6.fr>
To: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
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Cc: Christoph Hellwig <hch@infradead.org>, Tejun Heo <tj@kernel.org>,
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	ksummit-discuss@lists.linuxfoundation.org,
	Shuah Khan <shuah.kh@samsung.com>
Subject: Re: [Ksummit-discuss] [TECH TOPIC] Fix devm_kzalloc, its users,
 or both
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On Sat, 1 Aug 2015, Laurent Pinchart wrote:

> On Friday 31 July 2015 09:53:46 Christoph Hellwig wrote:
> > On Fri, Jul 31, 2015 at 06:34:21PM +0200, Julia Lawall wrote:
> > > How is this different from the free happening explicitly in the remove
> > > function?
> > 
> > It's not.  The real problem is that people don't understand life time
> > rules and expect magic interfaces to fix it for them.
> 
> Exactly. I see two solutions for that, either making people understand life 
> time rules, or creating interfaces that really fix it for them. devm_kzalloc() 
> isn't such an interface (and I'm fine if we believe it shouldn't be), but it 
> unfortunately gives driver developers the impression that it is supposed to 
> fix the problem. If we conclude that the problem is between the chair and the 
> keyboard of driver developers then we'll need to start being more vocal about 
> it.

Currently, is there any documentation about when these functions can be
used?  All I remember seeing is a discussion of what the functions do and
what functions are available.  But nothing about when they should and
should not be used.

julia