From mboxrd@z Thu Jan  1 00:00:00 1970
From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Subject: Re: [PATCH] xen: change XEN_PLATFORM_PCI to bool
	default y
Date: Wed, 21 Sep 2011 17:10:55 -0400
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To: Ian Campbell <Ian.Campbell@eu.citrix.com>
Cc: "jeremy@goop.org" <jeremy@goop.org>, "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>, Stefano Stabellini <Stefano.Stabellini@eu.citrix.com>
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On Wed, Sep 21, 2011 at 08:08:15PM +0100, Ian Campbell wrote:
> On Wed, 2011-09-21 at 19:51 +0100, Konrad Rzeszutek Wilk wrote:
> > On Wed, Sep 21, 2011 at 01:37:50PM +0100, stefano.stabellini@eu.citrix.com wrote:
> > > From: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
> > > 
> > > The xen-platform-pci module is small and for PV on HVM guests is a
> > 
> > How small?
> 
> IIRC it is single digit numbers of kb.
> 
> >  Does it get removed from memory if it never gets loaded?
> > 
> > > requirement for xenbus.
> > 
> > Ok, should it then have a depency on XenBus as well?
> 
> xenbus can't be a module (which is why allowing platform-pci to be is
> causing problems).
> 
> > Linus does not like the 'default y' very much. He actually dislikes
> > it quite much as I found when he tore Dan's behind about cleancache.
> 
> In particular case the option is gated on a dependency on another Xen
> option (PVHVM) which doesn't default on. But if you do select PVHVM you
> certainly want this option, so I think that's ok (why else would
> 'default y' even exist?)
> 
> > .. so I think making it 'default n' is a better option or perhaps
> > making it depend on some other functionality? Or perhaps just remove
> > the tristate/bool altogether so it gets activated if XEN_PVHVM
> > is set?
> > 
> > Or remove the XEN_PLATFORM_PCI config option completly and make the
> > config files that build this driver be CONFIG_XENPVHM dependent?
> 
> That would work too. Even better would be to make it an invisible
> Kconfig symbol which PVHVM just selects.
<nods>
Or that since you can't really do PVHVM without the platform PCI driver.