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From: Roland Dreier <roland@kernel.org>
Date: Wed, 11 Jun 2014 15:26:12 -0700
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To: James Bottomley <James.Bottomley@hansenpartnership.com>
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Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>,
	Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
	David Vrabel <david.vrabel@citrix.com>,
	"ksummit-discuss@lists.linuxfoundation.org"
	<ksummit-discuss@lists.linuxfoundation.org>
Subject: Re: [Ksummit-discuss] Topic: Removal of code that is still in use
 by users but there is a better code.
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On Wed, Jun 11, 2014 at 3:17 PM, James Bottomley
<James.Bottomley@hansenpartnership.com> wrote:
> This would eventually become like CONFIG_EXPERIMENTAL before somebody
> put it out of its misery: a pointless thing which everybody enables.

Probably so.

> Could we just step back and ask what the burning need to do this (at
> least for drivers; I understand the ABI deprecation headache) is?  Most
> driver code for obsolete things harmlessly compiles; why bother trying
> to hunt them down and shoot them when they're not really causing
> offence?

Every time a developer wants to change a core API, that developer
needs to patch every driver that uses the API.  Every old, unused,
bitrotten driver we have in the tree is 100% wasted work, and often a
substantial amount of work because it's really hard even to understand
how those drivers are (mis)using the API being changed.

 - R.