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From: Paul Brook <paul@codesourcery.com>
Subject: Re: [Qemu-devel] [4261] Errors while registering ioports are not
	fatal (Glauber Costa).
Date: Sat, 26 Apr 2008 21:08:49 +0100
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To: andrzej zaborowski <balrogg@gmail.com>
Cc: qemu-devel@nongnu.org

On Saturday 26 April 2008, andrzej zaborowski wrote:
> On 26/04/2008, Paul Brook <paul@codesourcery.com> wrote:
> > On Saturday 26 April 2008, Andrzej Zaborowski wrote:
> >  > Revision: 4261
> >  >          
> >  > http://svn.sv.gnu.org/viewvc/?view=rev&root=qemu&revision=4261 Author:
> >  >   balrog
> >  > Date:     2008-04-26 16:04:29 +0000 (Sat, 26 Apr 2008)
> >  >
> >  > Log Message:
> >  > -----------
> >  > Errors while registering ioports are not fatal (Glauber Costa).
> >
> >  Why shouldn't they be fatal? How can this be anything other than a
> > serious bug in the device emulation?
>
> This change is perhaps not useful, it would be useful with hot-plugged
> / proxied pci devices.  

I fail to see how hotplugging or proxing has anything to do with it. IO port 
registration is not something that can reasonably fail.

If the real problem is that we can't cope with multiple devices registering 
the same IO port than you need to fix that. Blindly punting to the caller to 
cope is IMHO not an acceptable solution, especially when none of the callers 
check the return value.

Paul