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Date: Wed, 15 Feb 2017 11:57:45 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: Peter Zijlstra <peterz@infradead.org>
cc: LKML <linux-kernel@vger.kernel.org>, Gabriel C <nix.or.die@gmail.com>,
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Subject: Re: [patch 1/2] x86/platform/goldfish: Prevent unconditional
 loading
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References: <20170215101149.937286619@linutronix.de> <20170215102145.074836404@linutronix.de> <20170215105301.GB6557@twins.programming.kicks-ass.net>
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On Wed, 15 Feb 2017, Peter Zijlstra wrote:
> On Wed, Feb 15, 2017 at 11:11:50AM +0100, Thomas Gleixner wrote:
> > The goldfish platform code registers the platform device unconditionally
> > which causes havoc in several ways if the goldfish_pdev_bus driver is
> > enabled:
> > 
> >  - Access to the hardcoded physical memory region, which is either not
> >    available or contains stuff which is completely unrelated.
> > 
> >  - Prevents that the interrupt of the serial port can be requested
> > 
> >  - In case of a spurious interrupt it goes into a infinite loop in the
> >    interrupt handler of the pdev_bus driver (which needs to be fixed
> >    seperately).
> > 
> > Add a 'goldfish' command line option to make the registration opt-in when
> > the platform is compiled in.
> > 
> > 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!
> > 
> > Fixes: ddd70cf93d78 ("goldfish: platform device for x86")
> > Reported-by: Gabriel C <nix.or.die@gmail.com>
> > Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> > Cc: stable@vger.kernel.org
> 
> Just thinking, could we not simply delete this entire driver and use
> x86-DT support to setup this platform?

That would be the proper solution and that's what ARM probably does already.

Thanks,

	tglx