From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marcelo Tosatti <mtosatti@redhat.com>
Subject: Re: KVM: MMU: rmap_write_protect() hugepage iteration bug
Date: Sun, 8 Jun 2008 21:20:41 -0300
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Cc: Avi Kivity <avi@qumranet.com>, kvm-devel <kvm@vger.kernel.org>
To: Andrea Arcangeli <andrea@qumranet.com>
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On Sun, Jun 08, 2008 at 10:30:37PM +0200, Andrea Arcangeli wrote:
> On Sun, Jun 08, 2008 at 04:52:15PM -0300, Marcelo Tosatti wrote:
> > We do. The case is were you have two entries in the array. rmap_remove
> > will first remove the entry at index 0, and move the entry at index 1 to
> > 0.
> > 
> > Then we call "rmap_next()" with a non-NULL spte, which will skip the
> > only remaining entry at index 0. IOW rmap_next() requires the spte
> > argument to be NULL if the array has one valid entry.
> 
> How exactly we could call rmap_next with not-NULL spte after any
> rmap_remove with your last patch applied?

With the original code.