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Date: Fri, 5 Aug 2011 16:27:37 +0200
From: Christoph Hellwig <hch@lst.de>
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Subject: Re: [Qemu-devel] Safely reopening image files by stashing fds
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To: Stefan Hajnoczi <stefanha@gmail.com>
Cc: Kevin Wolf <kwolf@redhat.com>, Paolo Bonzini <pbonzini@redhat.com>, Anthony Liguori <aliguori@us.ibm.com>, qemu-devel <qemu-devel@nongnu.org>, Supriya Kannery <supriyak@linux.vnet.ibm.com>

On Fri, Aug 05, 2011 at 10:27:00AM +0100, Stefan Hajnoczi wrote:
> > Why not do the latter unconditionally?
> 
> Because you cannot change O_DIRECT on an open fd :(.  This is why
> we're going through this pain.

You can.  What you can't right now is O_SYNC, but we're going to change
that.