Oneiric: [PATCH] (UBUNTU: Sauce) Match jack input devices and pcm devices for HDMI

Leann Ogasawara leann.ogasawara at
Wed Aug 31 21:35:15 UTC 2011

On Wed, 2011-08-31 at 09:18 +0200, David Henningsson wrote:
> On 08/30/2011 03:48 PM, Tim Gardner wrote:
> > So, you're asking to have a patch applied that has general impact on all
> > platforms with an HDMI port, which by your own admission has not had
> > widespread testing, and has not been agreed to or fully reviewed by
> > upstream maintainers.
> >
> > The kernel is in Beta freeze right now. What would your call be if you
> > were in the same position?
> If I were in the same position:
> First and foremost, I would start with a warm, welcoming and encouraging 
> attitude towards patches. A patch sent here, means someone not only 
> wants to improve Linux in general, but also cares in special for Ubuntu, 
> and has taken the time and effort to backport a patch to suit Ubuntu's 
> particular kernel version. In this case, the patch author is a Canonical 
> employee so this is not surprising, but nevertheless, this is a really 
> good thing and should be encouraged.

Let me just start by saying that we really appreciate all the work that
you've done with regards to the audio subsystem.  Your interaction with
upstream and the bug fixes you've provided for Ubuntu have been much
appreciated and I encourage you to keep up the good work.

> With that positive attitude in mind, I would do a review. The review 
> would, of course, take regression risk into account - a kernel bug can 
> cause the system to fail in the most horrifying ways - but also weigh 
> that against the possible positive outcomes of applying the patch, i e 
> why it's needed in the first place. If I'm not qualified to make a 
> review, I would find someone who is, to make the opinion for me.

Because we do consider you one of our knowledge experts in the audio
area, I believe Tim was wanting a bit more reassurance and confidence
from you with regards to the patch.  Having recognized the potential for
widespread impact, I do feel he was doing his job as one of the
maintainers of the Ubuntu kernel to make sure we're not introducing
regressions, especially being so close to Beta for Oneiric.

> The review in this case would notice that it impacts most people with 
> working HDMI audio which means both higher risk and gain. OTOH, the code 
> path is simple, which means that successful testing on one machine would 
> make it unlikely to fail on another.
> If I'm still unsure of regressions even after having done the review, I 
> would make sure testing of the patch is done. If I have time, I do the 
> testing myself, or if I don't, ask for someone to test it for me, but do 
> what I can to help, e g by building a test kernel and provide 
> instructions as of how to do the test. If testing with positive result 
> is all that's needed before applying the patch, I would communicate that 
> clearly, among with a deadline explaining when the testing must be 
> completed.

I've built a test kernel with your patch applied and placed it at the
following location:

If you can, could you please test and confirm this resolves the issue at
hand and also doesn't introduce any regressions on a few existing
systems with working HDMI audio (whatever access to systems you have on
hand would suffice).  Please keep in mind that Oneiric Kernel Freeze is
Thurs Sept 15, so if I could get your feedback before then I'd be happy
to try and get this applied before we hit the freeze date.

Thanks in advance,

More information about the kernel-team mailing list