From mboxrd@z Thu Jan  1 00:00:00 1970
From: Greg KH <greg@kroah.com>
Subject: Re: [PATCH] tty/powerpc: fix build break with ehv_bytechan.c on
 allyesconfig
Date: Thu, 25 Aug 2011 12:03:30 -0700
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To: Timur Tabi <timur@freescale.com>
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On Thu, Aug 25, 2011 at 01:51:20PM -0500, Timur Tabi wrote:
> Greg KH wrote:
> > But don't you really want this type of check at runtime?  What happens
> > if you load this driver on a machine that is not a guest?  Will things
> > break?  Shouldn't you still refuse to load somehow?
> 
> This is in the udbg code, which falls under the category of, "turn this on only
> if you know what you're doing."
> 
> The udbg code runs very early, before the device tree is available.  There's no
> way of knowing at this point whether or not we're running under a hypervisor.
> If you turn on udbg support, then it means that you're trying to do some very
> specific debugging on a specific platform.
> 
> So I'm not removing this code just to fix the build break.  It really should
> never have been there in the first place.

Ok, thanks for the details, I'll queue up the patch in a bit.

greg k-h