From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marcelo Tosatti <mtosatti@redhat.com>
Subject: Re: [patch 3/4] KVM: MMU: reload request from GET_DIRTY_LOG path
Date: Wed, 8 Oct 2014 16:22:31 -0300
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> > 
> > Argh, lets try again:
> > 
> > skip_pinned = true
> > ------------------
> > 
> > mark page dirty, keep spte intact
> > 
> > called from get dirty log path.
> > 
> > skip_pinned = false
> > -------------------
> > reload remote mmu
> > destroy pinned spte.
> > 
> > called from: dirty log enablement, rmap write protect (unused for pinned
> > sptes)
> > 
> > 
> > Note this behaviour is your suggestion:
> 
> Yes, I remember that and I thought we will not need this skip_pinned
> at all.  For rmap write protect case there shouldn't be any pinned pages,
> but why dirty log enablement sets skip_pinned to false? Why not mark
> pinned pages as dirty just like you do in get dirty log path?

Because if its a large spte, it must be nuked (or marked read-only,
which for pinned sptes, is not possible).