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Date: Wed, 15 Feb 2017 15:52:28 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: Alan Cox <alan@linux.intel.com>
cc: Peter Zijlstra <peterz@infradead.org>,
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        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
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Subject: Re: [patch 1/2] x86/platform/goldfish: Prevent unconditional
 loading
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On Wed, 15 Feb 2017, Alan Cox wrote:

> > > > I'm seriously grumpy about this engineering trainwreck, which has
> > > > seven
> > > > SOBs from Intel developers for 50 lines of code. And none of them
> > > > figured
> > > > out that this is broken. Impressive fail!
> 
> It was discussed at the time, documented at the time.

I just have a hard time to find that documentation. It's definitely not in
the kernel source, unless you qualify the help text of CONFIG_GOLDFISH as
such:

     Enable support for the Goldfish virtual platform used primarily
     for Android development. Unless you are building for the Android
     Goldfish emulator say N here.

which does not help for randconfig and other builds and does not prevent
users from enabling it accidentaly. That all wouldn't be as bad if at least
the minimal provisioning of damage prevention would have been done.

> Unfortunately the people who did the emulator didn't feel the urge to
> provide a way to detect the platform was Goldfish.

Sure, and the people shoving it into the kernel didn't feel the urge to
enforce that.

> Historically it also used its own custom device discovery scheme. Given
> the limited use of older versions of Goldfish it might well make sense
> to remove support for the older emulator versions.

I'm all for it.

Thanks,

	tglx