From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ian Campbell <ian.campbell@citrix.com>
Subject: Re: [PATCH 3/3] tools: introduce parameter max_ranges.
Date: Wed, 20 Jan 2016 10:16:18 +0000
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To: "Tian, Kevin" <kevin.tian@intel.com>, "Yu, Zhang" <yu.c.zhang@linux.intel.com>, Wei Liu <wei.liu2@citrix.com>, Paul Durrant <Paul.Durrant@citrix.com>
Cc: "Keir (Xen.org)" <keir@xen.org>, Andrew Cooper <Andrew.Cooper3@citrix.com>, "xen-devel@lists.xen.org" <xen-devel@lists.xen.org>, Stefano Stabellini <Stefano.Stabellini@citrix.com>, "Lv,
	Zhiyuan" <zhiyuan.lv@intel.com>, "jbeulich@suse.com" <jbeulich@suse.com>
List-Id: xen-devel@lists.xenproject.org

On Wed, 2016-01-20 at 03:58 +0000, Tian, Kevin wrote:
> > From: Yu, Zhang [mailto:yu.c.zhang@linux.intel.com]
> > Sent: Wednesday, January 20, 2016 11:33 AM
> > > As a feature this write-protection has nothing to be GPU
> > > virtualization specific.
> > > In the future the same mediated pass-through idea used in XenGT may
> > > be
> > > used on other I/O devices which need to shadow some structure w/
> > > requirement
> > > to write-protect guest memory. So it's not good to tie this to either
> > > XenGT
> > > or GTT.
> > > 
> > Thank you, Kevin.
> > Well, if this parameter is not supposed to be xengt specific, we do not
> > need to connect it with any xengt flag such as ."vgt=1" or "GVT-g=1".
> > Hence the user will have to configure the max_wp_ram_ranges himself,
> > right?
> > 
> 
> Not always. The option can be configured manually by the user, or 
> automatically set in the code when "vgt=1" is recognized.

Is the latter approach not always sufficient? IOW, if it can be done
automatically, why would the user need to tweak it?

Ian.