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: Tue, 19 Jan 2016 15:18:45 +0000
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To: Wei Liu <wei.liu2@citrix.com>, Paul Durrant <Paul.Durrant@citrix.com>
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On Tue, 2016-01-19 at 15:04 +0000, Wei Liu wrote:

This patch doesn't seem to have been CCd to the tools maintainers, adding
Ian too, I think everyone else was picked up along the way.

Please use ./scripts/get_maintainers.pl in the future.

> On Tue, Jan 19, 2016 at 02:47:40PM +0000, Paul Durrant wrote:
> [...]
> > > ranges so perhaps the parameter name could be
> > > 'max_wp_memory_ranges'?
> > > > 
> > > 
> > > What does "WP" mean? "Write Protected"?
> > > 
> > 
> > Yes.
> > 
> > > Is this parameter closely related to IOREQ server? Should it contain
> > > "ioreq" somehow?
> > > 
> > 
> > It is closely related but ioreq server is an implementation detail so
> > do we want to expose it as a tunable? The concept we need to capture
> > is that the toolstack can tune the limit of the maximum number of
> > pages in the VM that can be set such that writes are emulated (but
> > reads are as for normal ram). Or I guess we could get very specific
> > and call it something like 'max_gtt_shadows'?
> 
> I would prefer generic concept in this case ("wp"). Let's wait a bit for
> other people to voice their opinion.
> 
> Whichever one we pick it the meaning of the acronym needs to be clearly
> documented...

I've got no ideas for a better name, "max_ranges" is clearly too generic
though.

One thought -- does XenGT require some other configuration option to enable
it or maybe a privilege which the target domain must necessarily have?
Could we use something like one of those to cause the t/stack to just DTRT
without the user having to micromanage the amount of pages which are
allowed to have this property?

> 
> Wei.
> 
> > 
> > > Wei.
> 
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