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Subject: Re: [ANNOUNCE] Status of unlocked_qcmds=1 operation for .37
From: James Bottomley <James.Bottomley@suse.de>
To: Andi Kleen <ak@linux.intel.com>
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Date: Wed, 27 Oct 2010 09:27:38 -0500
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On Wed, 2010-10-27 at 09:53 +0200, Andi Kleen wrote:
> > This sounds like a pretty reasonable compromise that I think is slightly
> > less risky for the LLDs with the ghosts and cob-webs hanging off of
> > them.
> 
> They won't get tested either next release cycle. Essentially
> near nobody uses them.
> 
> > 
> > What do you think..?
> 
> Standard linux practice is to simply push the locks down. That's a pretty
> mechanical operation and shouldn't be too risky
> 
> With some luck you could even do it with coccinelle.

Precisely ... if we can do the push down now as a mechanical
transformation we can put it in the current merge window as a low risk
API change.  This gives us optimal exposure to the rc sequence to sort
out any problems that arise (or drivers that got missed) with the lowest
risk of such problems actually arising.  Given the corner cases and the
late arrival of fixes, the serial number changes are just too risky for
the current merge window.  Having an API that changes depending on a
flag is also a high risk process because it's prone to further sources
of error.

James