We Do Not Break Userspace

Linus Torvalds on what classifies as a bug in the kernel.

From Linus Torvalds <>
Date Sun, 23 Dec 2012 09:36:15 -0800
Subject Re: [Regression w/ patch] Media commit causes user space to misbahave (was: Re: Linux 3.8-rc1)
On Sun, Dec 23, 2012 at 6:08 AM, Mauro Carvalho Chehab  
<mchehab@redhat.com> wrote:  
> Are you saying that pulseaudio is entering on some weird loop if the  
> returned value is not -EINVAL? That seems a bug at pulseaudio.  


It's a bug alright - in the kernel. How long have you been a  
maintainer? And you *still* haven't learnt the first rule of kernel  

If a change results in user programs breaking, it's a bug in the  
kernel. We never EVER blame the user programs. How hard can this be to  

To make matters worse, commit f0ed2ce840b3 is clearly total and utter  
CRAP even if it didn't break applications. ENOENT is not a valid error  
return from an ioctl. Never has been, never will be. ENOENT means "No  
such file and directory", and is for path operations. ioctl's are done  
on files that have already been opened, there's no way in hell that  
ENOENT would ever be valid.  

> So, on a first glance, this doesn't sound like a regression,  
> but, instead, it looks tha pulseaudio/tumbleweed has some serious  
> bugs and/or regressions.  

Shut up, Mauro. And I don't _ever_ want to hear that kind of obvious  
garbage and idiocy from a kernel maintainer again. Seriously.  

I'd wait for Rafael's patch to go through you, but I have another  
error report in my mailbox of all KDE media applications being broken  
by v3.8-rc1, and I bet it's the same kernel bug. And you've shown  
yourself to not be competent in this issue, so I'll apply it directly  
and immediately myself.  


Seriously. How hard is this rule to understand? We particularly don't  
break user space with TOTAL CRAP. I'm angry, because your whole email  
was so _horribly_ wrong, and the patch that broke things was so  
obviously crap. The whole patch is incredibly broken shit. It adds an  
insane error code (ENOENT), and then because it's so insane, it adds a  
few places to fix it up ("ret == -ENOENT ? -EINVAL : ret").  

The fact that you then try to make *excuses* for breaking user space,  
and blaming some external program that *used* to work, is just  
shameful. It's not how we work.  

Fix your f*cking "compliance tool", because it is obviously broken.  
And fix your approach to kernel programming.