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From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Thu, 13 Jun 2013 00:11:39 +1000
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Subject: Re: [Qemu-devel] [Qemu-ppc]  broken incoming migration
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Alexey Kardashevskiy <aik@ozlabs.ru>, Peter Lieven <pl@kamp.de>, "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, "qemu-ppc@nongnu.org" <qemu-ppc@nongnu.org>, Wenchao Xia <xiawenc@linux.vnet.ibm.com>, David Gibson <david@gibson.dropbear.id.au>

On Wed, 2013-06-12 at 10:00 -0400, Paolo Bonzini wrote:
> The only bug we have is not a performance bug related to compression;
> it's that writing zero pages breaks overcommit.  Let's fix that, and
> only that.

Right, do we have a way to madvise "throw away" these instead ? Or do we
have a way to track that the platform init code did write something
there and only clear *those* pages ?

Cheers,
Ben.