From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alexander Graf <agraf@suse.de>
Subject: Re: [Qemu-devel] [PATCH] kvm: Fix memory slot page alignment logic
Date: Mon, 10 Nov 2014 15:48:54 +0100
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Cc: Igor Mammedov <imammedo@redhat.com>,
	kvm-devel <kvm@vger.kernel.org>,
	QEMU Developers <qemu-devel@nongnu.org>,
	qemu-stable <qemu-stable@nongnu.org>,
	Stuart Yoder <stuart.yoder@freescale.com>,
	"qemu-ppc@nongnu.org" <qemu-ppc@nongnu.org>,
	Paolo Bonzini <pbonzini@redhat.com>
To: Peter Maydell <peter.maydell@linaro.org>
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On 10.11.14 14:55, Peter Maydell wrote:
> On 10 November 2014 13:16, Alexander Graf <agraf@suse.de> wrote:
>> Sorry, I don't understand this paragraph. Memory slots in general are
>> accelerations for memory access - for MMIO (RAM is usually aligned), KVM
>> can always exit to QEMU and just do a manual MMIO exit.
> 
> ...you're a bit stuck if you were hoping to execute code from
> that RAM, though, so they're not *purely* acceleration, right?

Yes and no. Technically, there's no reason KVM couldn't do an MMIO exit
dance to fetch the next instruction. From user space this should be
indistinguishable.

Today, I don't think it's implemented though :).


Alex