From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@redhat.com>
Subject: Re: qemu vs. kvm: When to flush the coalesced mmio buffer?
Date: Mon, 03 Jan 2011 14:32:16 +0200
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Cc: kvm <kvm@vger.kernel.org>, qemu-devel <qemu-devel@nongnu.org>
To: Jan Kiszka <jan.kiszka@web.de>
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On 01/03/2011 02:11 PM, Jan Kiszka wrote:
> Hi again,
>
> another subtle difference between qemu-kvm and upstream:
>
> When we leave the guest for an IO window (KVM_RUN returns EINTR or
> EAGAIN), we call kvm_flush_coalesced_mmio_buffer in qemu-kvm but not in
> upstream. When version is better? I can't find any rationales in both
> git logs.

We must flush on EINTR, otherwise a live migration can leave some mmios 
in the source host and not replay them on the destination host.

(plus, as Gleb says, if you're in userspace you might as well flush)

-- 
error compiling committee.c: too many arguments to function